Added twopar - an example program to make an additive table model with two interpolation parameters. Also fixed a couple of potential problems in the wftbmd routine and the onepar program.
Keywords: HEAsoft, xspec
Thursday, October 19, 2006
Monday, October 16, 2006
filter time scc
Fixed a bug in the xselect "filter time scc" command which was reported by Phil Evans. In earlier versions of the program the numbers entered if a lightcurve had been extracted were relative to the offset SCC value written in the header of the plot. This behaviour was unintentionally changed in v2.4 to require the absolute SCC number to be entered. The old behaviour has now been restored by editing the routine filter_time_cursor in xsel_utils.f.
Update 10/26/06 : Evert Rol reported that using 'r' as the second option in a time interval gives an error. This would due to a parsing mistake in the str2sec routine.
Keywords: HEAsoft
Update 10/26/06 : Evert Rol reported that using 'r' as the second option in a time interval gives an error. This would due to a parsing mistake in the str2sec routine.
Keywords: HEAsoft
flx2xsp and wtpha
Created a new version of wtpha - called wtpha3 - which optionally writes multiple spectra in typeII format. Then used this in an upgrade of flx2xsp which can read multiple spectra from the ascii file and write them to a single FITS spectral file. This new option is invoked using the nspec parameter.
Keywords: HEAsoft
Keywords: HEAsoft
Wednesday, October 04, 2006
Preprints
Sahu et al. use HST observations of a Galactic bulge field to find transiting planets, 5 of which have periods < href="http://arXiv.org/abs/astro-ph/0610115">Muchovej et al. report first results from the Sunyaev-Zel'dovich Array of measurements of 3 high redshift clusters. Measured cluster properties are consistent with those determined from X-ray observations.
Belsole et al. present results from Chandra & XMM observations of the environments of 19 radio galaxies at 0.5.
Brenneman & Reynolds use Fe-K line observations with XMM and a new model (kerrdisk) to constrain the black hole spin in MCG-6-30-15.
Ziaeepour & Rosen use the Chandra Multi-Wavelength public data to discuss statistical classification of X-ray sources.
Berti & Cardoso discuss how to distinguish massive BHs from boson stars using LISA observations.
Belsole et al. present results from Chandra & XMM observations of the environments of 19 radio galaxies at 0.5.
Brenneman & Reynolds use Fe-K line observations with XMM and a new model (kerrdisk) to constrain the black hole spin in MCG-6-30-15.
Ziaeepour & Rosen use the Chandra Multi-Wavelength public data to discuss statistical classification of X-ray sources.
Berti & Cardoso discuss how to distinguish massive BHs from boson stars using LISA observations.
Monday, October 02, 2006
Suzaku mdb change
Updated xselect.mdb because the lststr setting for Suzaku XIS was incorrect for the output from v1 processing. The make obscat command does not work without this change.
Also, updated my brief notes on using xselect for Suzaku analysis.
Keywords: Suzaku, HEAsoft, xselect
Also, updated my brief notes on using xselect for Suzaku analysis.
Keywords: Suzaku, HEAsoft, xselect
Monday, September 25, 2006
Preprints
Ota et al. find no evidence using Suzaku data for bulk motions in the Centaurus cluster in contrast to the claim using Chandra data.
Weisskopf et al. place stringent upper limits on X-ray emission from a single, cool, magnetic WD. They also note a statistical methodology for detecting a source when there are very few counts in the source and background.
Schwope et al. conclude on the basis of deep XMM spectroscopy that one at least of the two absorption lines in the spectrum of the isolated NS RBS1223 must be of atomic origin because their flux ratio is not consistent with a cyclotron origin for both.
Balestra et al. combine the analysis of Chandra observations of 56 clusters to examine the Fe abundance change with redshift finding a decrease parametrized as (1+z)^-1.25.
Cen shows that if gas disk accretion onto a SMBH is only efficient for a surface density > 10g/cm^2 then the SMBH mass - bulge velocity dispersion relation results.
Kondratko et al. report the discovery of 5 more AGN with water masers.
Schmidt & Allen present Chandra observations of 34 massive, dynamically relaxed clusters and find that the NFW model provides an acceptable fit in ~80% of cases.
Jeffery et al. support the proposal that the SNIa 2003fg had a progenitor above the Chandrasekhar limit.
Bogdanovic et al. discuss possible EM signals from close binary SMBH.
Weisskopf et al. place stringent upper limits on X-ray emission from a single, cool, magnetic WD. They also note a statistical methodology for detecting a source when there are very few counts in the source and background.
Schwope et al. conclude on the basis of deep XMM spectroscopy that one at least of the two absorption lines in the spectrum of the isolated NS RBS1223 must be of atomic origin because their flux ratio is not consistent with a cyclotron origin for both.
Balestra et al. combine the analysis of Chandra observations of 56 clusters to examine the Fe abundance change with redshift finding a decrease parametrized as (1+z)^-1.25.
Cen shows that if gas disk accretion onto a SMBH is only efficient for a surface density > 10g/cm^2 then the SMBH mass - bulge velocity dispersion relation results.
Kondratko et al. report the discovery of 5 more AGN with water masers.
Schmidt & Allen present Chandra observations of 34 massive, dynamically relaxed clusters and find that the NFW model provides an acceptable fit in ~80% of cases.
Jeffery et al. support the proposal that the SNIa 2003fg had a progenitor above the Chandrasekhar limit.
Bogdanovic et al. discuss possible EM signals from close binary SMBH.
Monday, September 18, 2006
Preprints
Tegmark et al. present the cosmological results from the real-space power spectrum based on the SDSS luminous red galaxy survey. Baryon oscillations are clearly detected at a mean z=0.35.
Anderson et al. continue their work cross-correlating RASS sources with the SDSS to generate a large sample of X-ray emitting AGN.
Pratt et al. present temperature profiles from XMM observations of a representative sample of nearby clusters. Outside the core they find similar profiles which agree well with numerical simulations.
Hogan summarizes current ideas on gravitational wave tests for new physics.
Brewer et al. describe a Bayesian MCMC approach to extract stellar oscillation frequencies from light curves.
Elvis et al. describe an active-optics concept for making high resolution mirrors with low mass/unit area.
Poole et al. show the results of SPH simulations of mergers between idealised X-ray clusters. They reproduce the features observed in Chandra and XMM observations and note that neither of the compact cores of the merging clusters are disrupted.
Petric et al. put limits on extragalactic dust from the lack of a halo in a Chandra observation of a z=4.3 quasar.
Albrecht et al. is the report of the dark energy task force.
Wright describes a handy cosmology calculator for times and distances as a function of redshift.
Anderson et al. continue their work cross-correlating RASS sources with the SDSS to generate a large sample of X-ray emitting AGN.
Pratt et al. present temperature profiles from XMM observations of a representative sample of nearby clusters. Outside the core they find similar profiles which agree well with numerical simulations.
Hogan summarizes current ideas on gravitational wave tests for new physics.
Brewer et al. describe a Bayesian MCMC approach to extract stellar oscillation frequencies from light curves.
Elvis et al. describe an active-optics concept for making high resolution mirrors with low mass/unit area.
Poole et al. show the results of SPH simulations of mergers between idealised X-ray clusters. They reproduce the features observed in Chandra and XMM observations and note that neither of the compact cores of the merging clusters are disrupted.
Petric et al. put limits on extragalactic dust from the lack of a halo in a Chandra observation of a z=4.3 quasar.
Albrecht et al. is the report of the dark energy task force.
Wright describes a handy cosmology calculator for times and distances as a function of redshift.
Thursday, September 14, 2006
PGPLOT - new ps driver
There were a few problems in the HEAsoft 6 release stemming from the new PS driver we introduced. The QDP font command didn't work correctly, the grfont.dat file was switched from binary to ascii introducing conflicts if the user already had PGPLOT installed, and a new file pgprolog.ps was required also leading to potential conflicts. All these have been fixed in a patch available from the HEAsoft bugs page.
UPDATE: A couple more problems were spotted by Glenn Morris. Symbols didn't work correctly in sub and superscripts and several symbols did not plot. I fixed the sub and superscript problem and at the same time added the ability to deal with multiple levels of sub/superscripts. Some of the symbol problems were due to a typo. Others still remain because there is no equivalent in a PS font for some Hershey symbols. The most important one appears to be the Solar symbol. It may be necessary to handle this one as a special case by writing an "O" then backspacing and shifting vertically and writing a "."
Keywords: HEAsoft, pgplot
UPDATE: A couple more problems were spotted by Glenn Morris. Symbols didn't work correctly in sub and superscripts and several symbols did not plot. I fixed the sub and superscript problem and at the same time added the ability to deal with multiple levels of sub/superscripts. Some of the symbol problems were due to a typo. Others still remain because there is no equivalent in a PS font for some Hershey symbols. The most important one appears to be the Solar symbol. It may be necessary to handle this one as a special case by writing an "O" then backspacing and shifting vertically and writing a "."
Keywords: HEAsoft, pgplot
Preprints
Hicks et al. report on Chandra and optical observations of the CNOC subsample of EMSS clusters and find excellent agreement between X-ray, dynamical and lensing mass estimates.
Iye et al. find a galaxy at z=6.96 with star formation at ~10 Msun/yr.
Babich & Loeb claim that Thomson scattering off electrons in the outflows from Lyman Break Galaxies could produce CMB fluctuations on arcminute scales comparable to the level of those produced during reionization.
Kramer et al. summarize the results of 2.5 years of observations of the binary pulsar J0737 - these already match the predictions of GR to 0.05% and in future years will supersede the accuracy of Solar System tests.
Ballantyne et al. calculate Spitzer AGN luminosity functions using models of the CXRB and Cloudy.
Han & Zhang compare the windowed FFT and Hilbert-Huang analysis methods for Poisson X-ray data and conclude that the windowed FFT is far superior.
Vierdayanti et al analyze XMM spectra of 4 ULX sources and conclude that they can be explained by super-critical accretion (and hence slim disks) onto stellar mass BHs.
Feldmann et al. present ZEBRA, a Bayesian photometric redshift estimation code.
Hajian et al. describes the Hamiltonian Monte Carlo method applied to cosmological parameter estimation and notes that it offers efficiency advantages over MCMC.
Croston et al. have developed a regularization procedure for deprojecting and PSF-correcting XMM observations of clusters.
Iye et al. find a galaxy at z=6.96 with star formation at ~10 Msun/yr.
Babich & Loeb claim that Thomson scattering off electrons in the outflows from Lyman Break Galaxies could produce CMB fluctuations on arcminute scales comparable to the level of those produced during reionization.
Kramer et al. summarize the results of 2.5 years of observations of the binary pulsar J0737 - these already match the predictions of GR to 0.05% and in future years will supersede the accuracy of Solar System tests.
Ballantyne et al. calculate Spitzer AGN luminosity functions using models of the CXRB and Cloudy.
Han & Zhang compare the windowed FFT and Hilbert-Huang analysis methods for Poisson X-ray data and conclude that the windowed FFT is far superior.
Vierdayanti et al analyze XMM spectra of 4 ULX sources and conclude that they can be explained by super-critical accretion (and hence slim disks) onto stellar mass BHs.
Feldmann et al. present ZEBRA, a Bayesian photometric redshift estimation code.
Hajian et al. describes the Hamiltonian Monte Carlo method applied to cosmological parameter estimation and notes that it offers efficiency advantages over MCMC.
Croston et al. have developed a regularization procedure for deprojecting and PSF-correcting XMM observations of clusters.
Monday, September 11, 2006
Preprints
Koyama et al. present Suzaku XIS observations of the Galactic Center region. Using the observed Fe and Ni emission lines they show that the plasma is collisional and in ionization equilibrium with an Fe abundance ~3.5 times Solar.
Gregory uses a Bayesian Kepler periodogram to find a second planet orbiting HD208487.
Nagai et al. analyze simulated Chandra observations of clusters and conclude that the ISM mass is estimated correctly to better than 6% while the total gravitating mass estimate is biassed low by 5-20% due bulk motion pressure support.
Raymond et al. argue from dynamical simulations that planetary systems with "Hot Jupiters" can harbour Earth-analogs in the habitable zone.
McCarthy et al. compare WMAP3 results with baryon fractions from cluster observations and conclude that Omega_m is probably 0.28-0.39, higher than the WMAP3 best-fit value.
Centrella summarizes recent advances in numerical relativity and the calculations of BH merger gravitational waveforms.
Arzner et al. discuss the efficacy of various statistical methods in spectral fitting and advocate unbinned maximum likelihood.
Angus et al. argue that the "bullet cluster" results comparing X-ray and lensing images can be explained by a combination of MOND and 2eV neutrinos.
Paczynski proposes a number of projects using small (~10-30 cm) telescopes to look for variable objects. He also proposes a small telescope at L1 to give warning of "killer asteroids".
Stroeer et al. discuss automated Bayesian inference for LISA data analysis.
Vignali et al. select type 2 quasars on the basis of [OIII] emission then observe them with Chandra - their results support the idea that type 2 quasars are heavily absorbed in the X-ray.
Gregory uses a Bayesian Kepler periodogram to find a second planet orbiting HD208487.
Nagai et al. analyze simulated Chandra observations of clusters and conclude that the ISM mass is estimated correctly to better than 6% while the total gravitating mass estimate is biassed low by 5-20% due bulk motion pressure support.
Raymond et al. argue from dynamical simulations that planetary systems with "Hot Jupiters" can harbour Earth-analogs in the habitable zone.
McCarthy et al. compare WMAP3 results with baryon fractions from cluster observations and conclude that Omega_m is probably 0.28-0.39, higher than the WMAP3 best-fit value.
Centrella summarizes recent advances in numerical relativity and the calculations of BH merger gravitational waveforms.
Arzner et al. discuss the efficacy of various statistical methods in spectral fitting and advocate unbinned maximum likelihood.
Angus et al. argue that the "bullet cluster" results comparing X-ray and lensing images can be explained by a combination of MOND and 2eV neutrinos.
Paczynski proposes a number of projects using small (~10-30 cm) telescopes to look for variable objects. He also proposes a small telescope at L1 to give warning of "killer asteroids".
Stroeer et al. discuss automated Bayesian inference for LISA data analysis.
Vignali et al. select type 2 quasars on the basis of [OIII] emission then observe them with Chandra - their results support the idea that type 2 quasars are heavily absorbed in the X-ray.
Thursday, September 07, 2006
gti extension names for Suzaku
It appears we have an inconsistency in that the standard name for a gti extension used for suzaku is GTI however xselect is currently set up for STDGTI hence is used cleaned event files from processing. Changed xselect.mdb to to use GTI.
Tested what happens if xselect is used on an input event file with a gti name different from that set in the xselect.mdb. Reading event files with the "wrong" name for the gti extension doesn't seem to be a problem however using "load obscat" then "choose" produces an error message. I need to change the code so these cases are dealt with the same way. Also, shouldn't using DSS keywords get round this issue ?
Update: Modified xsel_read.f and xsel_mission.f so that the read and choose commands will work correctly for either STDGTI or GTI. Note that using DSS keywords doesn't help at present - should xselect be modified to use them ?
Keywords: HEAsoft, xselect, Suzaku
Tested what happens if xselect is used on an input event file with a gti name different from that set in the xselect.mdb. Reading event files with the "wrong" name for the gti extension doesn't seem to be a problem however using "load obscat" then "choose" produces an error message. I need to change the code so these cases are dealt with the same way. Also, shouldn't using DSS keywords get round this issue ?
Update: Modified xsel_read.f and xsel_mission.f so that the read and choose commands will work correctly for either STDGTI or GTI. Note that using DSS keywords doesn't help at present - should xselect be modified to use them ?
Keywords: HEAsoft, xselect, Suzaku
Tuesday, August 01, 2006
bldg2 printers
To print from the Unix shell under Tiger the printer name needs to include the machine name eg duplex4@lhea4.
Keywords: system
Keywords: system
Monday, July 31, 2006
Preprints
Davis et al. describe the multiwavelength extended Groth strip survey with observations from radio to X-ray.
Graham & Driver derive a quadratic relation between BH mass and bulge concentration.
Li Ji et al. develop a non-equilibrium ionization model for stellar cluster winds.
Bridges et al. do a full-up Bayesian analysis of the 3-year WMAP and LSS data and conclude that the n=1 spectrum can be ruled out and that the form of the deviation from n=1 differs from a power-law.
Malbon et al. graft black hole growth onto their galaxy formation model based on LCDM and predict the number and sizes of BH mergers.
Graham & Driver derive a quadratic relation between BH mass and bulge concentration.
Li Ji et al. develop a non-equilibrium ionization model for stellar cluster winds.
Bridges et al. do a full-up Bayesian analysis of the 3-year WMAP and LSS data and conclude that the n=1 spectrum can be ruled out and that the form of the deviation from n=1 differs from a power-law.
Malbon et al. graft black hole growth onto their galaxy formation model based on LCDM and predict the number and sizes of BH mergers.
Friday, July 28, 2006
xspec11 error in tclout compinfo
Jeremy Sanders points out that the number of parameters in the model returned by tclout compinfo is one too few. Simple error in tclout.c which is patched as 11.3.2v.
Keywords: HEAsoft, xspec
Keywords: HEAsoft, xspec
Monday, July 24, 2006
xspec 11 memory allocation errors in fakeit and tclout
Jeremy Sanders provided some fixes to memory allocation of strings in fakeit.c and tclout.c. Some sizes were being set without including the null at the end. Bug fix 11.3.2u.
Keywords: HEAsoft, xspec
Keywords: HEAsoft, xspec
Friday, July 14, 2006
Preprints
Bouwens & Illingworth look for z~7-8 galaxies in NICMOS data and find less candidates than expected implying rapid evolution in the most luminous galaxies.
Wednesday, July 12, 2006
fix to genrsp
Randall spotted that the new v2.0 genrsp was only creating half-gaussian responses. This was due to a stupid error in clcrsp.f. v2.01 should get into the HEAsoft 6.1 release.
Keywords: genrsp, HEAsoft
Keywords: genrsp, HEAsoft
Preprints
Diehl & Statler present results of analyzing Chandra observations of 54 normal ellipticals. They find little correlation between optical and X-ray emission and conclude that the X-ray emitting gas is generally out of equilibrium and does not retain information about the shape of the underlying potential.
Park et al. develop a Bayesian treatment of hardness ratios.
Wilman et al. present optical integrated field spectroscopy of the H-alpha luminous central galaxies in the four cooling flow clusters and find disturbed emission coincident with secondary galaxies.
Wickham et al. develop the use of reversible jump MCMC to study SMBH binary systems with LISA.
de Freitas Pacheco et al. estimate the capture rate of compact objects by SMBH.
Sanders presents a new technique for performing spatially-resolved spectroscopy by selecting regions based on surface-brightness contours of the smoothed image.
Loeb looks at thermal evaporation from clusters and notes this could lead to a loss of at least a tenth of the gas at the cluster virial temperature.
Schnittman et al. use relativistic MHD simulations of accretion onto a non-rotating BH to predict features of the high-frequency power spectrum.
Trimble et al. present their annual summary of the year in astrophysics.
Heinz et al. find using numerical simulations that radio source morphologies can be significantly changed by bulk flows in the cluster gas.
Beckmann et al. present the 20-40 keV AGN luminosity function based on Integral observations covering 25000 deg^2 and detecting 38 extragalactic objects.
Lauer et al. argue that for brightest cluster galaxies the BH mass correlation with bulge luminosity is more likely to be correct than that with bulge velocity dispersion.
Arun examines the differences in parameter estimation between 3.5PN and 2PN for LISA observations of BH mergers.
Babak et al. present "kludge" gravitational waveforms for compact objects inspiralling around massive black holes.
Park et al. develop a Bayesian treatment of hardness ratios.
Wilman et al. present optical integrated field spectroscopy of the H-alpha luminous central galaxies in the four cooling flow clusters and find disturbed emission coincident with secondary galaxies.
Wickham et al. develop the use of reversible jump MCMC to study SMBH binary systems with LISA.
de Freitas Pacheco et al. estimate the capture rate of compact objects by SMBH.
Sanders presents a new technique for performing spatially-resolved spectroscopy by selecting regions based on surface-brightness contours of the smoothed image.
Loeb looks at thermal evaporation from clusters and notes this could lead to a loss of at least a tenth of the gas at the cluster virial temperature.
Schnittman et al. use relativistic MHD simulations of accretion onto a non-rotating BH to predict features of the high-frequency power spectrum.
Trimble et al. present their annual summary of the year in astrophysics.
Heinz et al. find using numerical simulations that radio source morphologies can be significantly changed by bulk flows in the cluster gas.
Beckmann et al. present the 20-40 keV AGN luminosity function based on Integral observations covering 25000 deg^2 and detecting 38 extragalactic objects.
Lauer et al. argue that for brightest cluster galaxies the BH mass correlation with bulge luminosity is more likely to be correct than that with bulge velocity dispersion.
Arun examines the differences in parameter estimation between 3.5PN and 2PN for LISA observations of BH mergers.
Babak et al. present "kludge" gravitational waveforms for compact objects inspiralling around massive black holes.
Preprints
Dotti et al discuss the EM signals or binary BH mergers detectable by LISA.
Maschenko et al. show that random bulk gas motions in primordial galaxies act to flatten the central dark matter cusps and hence solve the discrepancy between the predicted sharp cusps and observed flattened distributions.
Juett et al. present absorption edge results for Ne and Fe using HETG observations of X-ray binaries. They measure the Fe depletion onto dust grains and the Ne ionization structure of the ISM.
Kewley et al. analyze 85224 emission-line galaxies from the SDSS and derive a classification scheme which cleanly separates star-forming galaxies, AGN-HII composites, Seyferts and LINERs.
Cornish & Porter used annealed MCMC to extract the parameters for a SMBH binary embedded in a simulated LISA datastream.
Fregeau et al. discuss the detection probabilities with LISA and LIGO for IMBH binary mergers.
Dai et al. stack RASS data for over 4000 clusters selected from the 2MASS catalog and conclude that the relationships between mass, X-ray temperature, and X-ray luminosity are consistent with those for X-ray selected clusters.
McClintock et al. place a lower limit on the dimensional spin parameter for the BH in GRS1915 of 0.98 by modelling the X-ray continuum.
Schurch & Done model the soft X-ray emission from AGN as a failed disk wind where material is blown off the inner regions of the disk and falls back down onto the outer regions.
Rephaeli et al. analyze > 500 ksec of RXTE data on A2163 and derive a model where ~25 of the 3-50 keV emission is from a non-thermal component.
Sun et al. present a survey of the X-ray coronae of galaxies in nearby clusters.
Maschenko et al. show that random bulk gas motions in primordial galaxies act to flatten the central dark matter cusps and hence solve the discrepancy between the predicted sharp cusps and observed flattened distributions.
Juett et al. present absorption edge results for Ne and Fe using HETG observations of X-ray binaries. They measure the Fe depletion onto dust grains and the Ne ionization structure of the ISM.
Kewley et al. analyze 85224 emission-line galaxies from the SDSS and derive a classification scheme which cleanly separates star-forming galaxies, AGN-HII composites, Seyferts and LINERs.
Cornish & Porter used annealed MCMC to extract the parameters for a SMBH binary embedded in a simulated LISA datastream.
Fregeau et al. discuss the detection probabilities with LISA and LIGO for IMBH binary mergers.
Dai et al. stack RASS data for over 4000 clusters selected from the 2MASS catalog and conclude that the relationships between mass, X-ray temperature, and X-ray luminosity are consistent with those for X-ray selected clusters.
McClintock et al. place a lower limit on the dimensional spin parameter for the BH in GRS1915 of 0.98 by modelling the X-ray continuum.
Schurch & Done model the soft X-ray emission from AGN as a failed disk wind where material is blown off the inner regions of the disk and falls back down onto the outer regions.
Rephaeli et al. analyze > 500 ksec of RXTE data on A2163 and derive a model where ~25 of the 3-50 keV emission is from a non-thermal component.
Sun et al. present a survey of the X-ray coronae of galaxies in nearby clusters.
extractor on OSF
The HEAsoft 6.1 version of extractor fails under OSF with
exception system: exiting due to internal error: out of memory trying to allocate exception system resources
We have no explanation for this at present. It appears to happen before any extractor code is executed.
Keywords: HEAsoft, extractor, OSF
exception system: exiting due to internal error: out of memory trying to allocate exception system resources
We have no explanation for this at present. It appears to happen before any extractor code is executed.
Keywords: HEAsoft, extractor, OSF
Tuesday, July 11, 2006
extractor on Intel Mac
Fixed a bug when writing the XRONOS window file which showed up on the Intel Mac although since it was a format statement error we should have run into it before. v4.67.
Keywords: HEAsoft, extractor
Keywords: HEAsoft, extractor
Monday, July 10, 2006
xselect.mdb for Suzaku
At Koji's suggestion changed mkf_def_expr to ae*.mkf, since all relevant parameters are now included in the mkf file, and mkf_rel_dir to ../../auxil to conform to the v1 processing output.
Keywords: HEAsoft, xselect, Suzaku
Keywords: HEAsoft, xselect, Suzaku
Friday, July 07, 2006
pgplot /gif and /ppm drivers
Created C implementations of the pgplot /gif and /ppm drivers. The fortran versions of these use %VAL so fail on some fortran compilers. Used f2c to create a candidate C version then did a fair amount of tidying up. Confirmed that the drivers work correctly under Tiger but they may need tweaking for other systems.
Update: Added C implementation of pgplot /wd driver. More careful testing showed up a few discrepancies between the output files from the Fortran and C versions. After fixing some bugs the /ppm and /wd drivers produced identical binary output files from the Fortran and C versions. The /gif drivers produced small differences however these output files appear to be time-dependent since both the Fortran and C implementations produce slightly different binary files in successive runs. This was because the CODE array was not completely initialized to zero (one dimension was looped from 0 to 4095 not 0 to 4097 as required).
Keywords : heasoft, pgplot
Update: Added C implementation of pgplot /wd driver. More careful testing showed up a few discrepancies between the output files from the Fortran and C versions. After fixing some bugs the /ppm and /wd drivers produced identical binary output files from the Fortran and C versions. The /gif drivers produced small differences however these output files appear to be time-dependent since both the Fortran and C implementations produce slightly different binary files in successive runs. This was because the CODE array was not completely initialized to zero (one dimension was looped from 0 to 4095 not 0 to 4097 as required).
Keywords : heasoft, pgplot
Tuesday, June 20, 2006
PostScript driver
Another couple of tweaks to the PS driver to fix bugs. The code included some instances of the
string "\\" which were assumed to be interpreted by the compiler as "\". This doesn't work on all compilers so replaced this with char(92). Also, the prolog was being written with two instances of "%% Orientation", one specifying Landscape and the other Portrait. This was confusing Illustrator on the Mac.
Keywords: HEAsoft, pgplot
string "\\" which were assumed to be interpreted by the compiler as "\". This doesn't work on all compilers so replaced this with char(92). Also, the prolog was being written with two instances of "%% Orientation", one specifying Landscape and the other Portrait. This was confusing Illustrator on the Mac.
Keywords: HEAsoft, pgplot
Tuesday, June 06, 2006
more XIS contamination models
After prompting by Aya Kubota I've made a model xiscoabh for the HXD nominal pointing position and xispcoab with an additional parameter giving the off-axis angle. Both these use the expression for column-depth vs off-axis angle from Dotani-san's e-mail.
Keywords: Suzaku
Keywords: Suzaku
max number of GTIs in extractor
Someone on the Japanese side of the Suzaku team ran into the limit of 40960 rows in a GTI file ! I've increased this to 100,000 but it would be good to remove this limit completely and go to dynamically-allocated memory.
Keywords: HEAsoft, extractor, xselect
Keywords: HEAsoft, extractor, xselect
Monday, June 05, 2006
rdrmf5 and variable length records
There were two cancelling bugs in rdrmf4 and rdrmf5. The code to find whether a column was variable length had an error so never returned true. However, the attempt to then read all the data for a variable length column in one go is incorrect use of cfitsio, which requires such columns to be read one row at a time. Fixed both these bugs. Note that some tools still call rdrmf4 - these should be updated.
Keywords: HEAsoft
Keywords: HEAsoft
Preprints
Lazendic et al. present results from the analysis of a 70 ksec Chandra HETG observation of Cas A and describe the techniques used on such a large and complex target.
Loewenstein looks at heavy metal creation in field and cluster galaxies and concludes that star formation is >3 times as efficient in clusters as in the field, mitigating the overcooling problem.
Bogdanov et al. propose that the tail in the spectrum of rotation-powered millisecond pulsars is due to Comptonization of the thermal polar cap emission.
Benford models jets and magnetic bubbles to argue that magnetic structures can persist long after the jet has turned off and this explains the bubbles seen in the ICM.
Miller et al. show from X-ray observations of GRO J1655 that the absorbing wind must be driven by magnetic forces internal to the disk.
Blundell et al. determine the low-energy cutoff for the energy of relativistic particles accelerated in radio lobe hot spots.
Krivonos et al. analyze Integral observations of the Galactic Ridge and show that in spectrum and spatial distribution it is consistent with a population of accreting magnetic white dwarf binaries.
Saunders et al. discuss the optimal sampling strategy for searching for periodic signals.
Pizzolato and Soker argue that the R-T instability in radio bubbles in cooling flow clusters is stabilised by the deceleration of the interface in the initial expansion of the bubble increasing the expected lifetime.
Hogan detects the production of gravitational wave bursts by light cosmic strings.
Loewenstein looks at heavy metal creation in field and cluster galaxies and concludes that star formation is >3 times as efficient in clusters as in the field, mitigating the overcooling problem.
Bogdanov et al. propose that the tail in the spectrum of rotation-powered millisecond pulsars is due to Comptonization of the thermal polar cap emission.
Benford models jets and magnetic bubbles to argue that magnetic structures can persist long after the jet has turned off and this explains the bubbles seen in the ICM.
Miller et al. show from X-ray observations of GRO J1655 that the absorbing wind must be driven by magnetic forces internal to the disk.
Blundell et al. determine the low-energy cutoff for the energy of relativistic particles accelerated in radio lobe hot spots.
Krivonos et al. analyze Integral observations of the Galactic Ridge and show that in spectrum and spatial distribution it is consistent with a population of accreting magnetic white dwarf binaries.
Saunders et al. discuss the optimal sampling strategy for searching for periodic signals.
Pizzolato and Soker argue that the R-T instability in radio bubbles in cooling flow clusters is stabilised by the deceleration of the interface in the initial expansion of the bubble increasing the expected lifetime.
Hogan detects the production of gravitational wave bursts by light cosmic strings.
Friday, June 02, 2006
fakeit in v12
Changes to support use of Gaussian statistics when simulating the model part of the source file. If there is a pre-existing dataset then its value of is_Poisson is used when faking. If there is no pre-existing dataset then Poisson statistics are used.
This is required for Swift BAT simulations but also should be useful for other instruments which have non-Poisson statistics.
Keywords: xspec, HEAsoft
This is required for Swift BAT simulations but also should be useful for other instruments which have non-Poisson statistics.
Keywords: xspec, HEAsoft
Thursday, June 01, 2006
PGPLOT PS driver
Made considerable simplification to the GRPSSY routine in psdriv.f. This was very baroque and I was able to reduce the code length by a factor of three and generate cleaner PS. This also fixed a nasty bug in the plot sens command in xspec.
Keywords: HEAsoft, pgplot
Keywords: HEAsoft, pgplot
Wednesday, May 31, 2006
xselect and filter col PI=...
Fixed the case that the user does a filter column on the spectrum column (PHA or PI). Before this was not working because I automatically add a filter between the minimum and maximum allowed values. The two sets of filters are ORed in extractor so the filter column has no effect. Removed the min to max filter if a filter column on the spectrum is present. There is a potential conflict if the user does both a filter pha and a filter column on the PI/PHA. In this case the filter pha is ignored.
It would be to good to support exclude ranges in extractor so that the user could specify eg filter column PI=!1600:1700 to get all channels except 1600-1700.
Keywords: HEAsoft, xselect
It would be to good to support exclude ranges in extractor so that the user could specify eg filter column PI=!1600:1700 to get all channels except 1600-1700.
Keywords: HEAsoft, xselect
more on xselect and filter time UT
Fixed further problems in filter time UT. Wrote a new wrap-up routine str2sec which converts a string of comma-delimited time specifications into an array of double precision SCC times. This replaces large chunks of code in xsl_time_cursor and xsl_enter_filter and eliminates most of the problems. Also fixed xsl_choose so that if the user loads an obscat and does a choose instead of read'ing files then the mjdrefi/f and timesys internal globals are set.
Keywords: xselect, HEAsoft
Keywords: xselect, HEAsoft
Tuesday, May 30, 2006
xselect and XMM response generation
Modified the XMM EPIC response generation perl script so that it uses the badpixel data. This required a new perl script (and code in xselect to call it) which copies the appropriate BADPIX## and EXPOSU## extensions from the event file to the spectrum file. At present this requires that there only be one event file from which the spectrum was extracted. If there are multiple event files then the user is advised to do an "extract event" then save the spectrum.
Moved XSL_RSPSAV from xsel_mission.f to xsel_utils.f since it has no mission-dependent code. Note that I slightly changed the behaviour of XSL_GRPSAV in the event that something goes wrong in getting the grouping.
Keywords: HEAsoft, xselect, XMM
Moved XSL_RSPSAV from xsel_mission.f to xsel_utils.f since it has no mission-dependent code. Note that I slightly changed the behaviour of XSL_GRPSAV in the event that something goes wrong in getting the grouping.
Keywords: HEAsoft, xselect, XMM
Wednesday, May 24, 2006
Gary Hinshaw: WMAP 3 year results
EUD colloquium by Gary Hinshaw, data lead on the WMAP mission. He summarized the science justification and history then launched into the the 3 year results. The gain calibration has been improved leading to slightly different results on the temperature power spectrum - particularly at the low l end - and of course the S/N is improved. The big new result is the polarization map which provides a much better measure of the optical depth to free electron scattering - this is significantly less than the best-fit from the 1-year results implying a later reionization epoch (400,000 years after inflation rather than 100,000 years). Since the optical depth is highly correlated with the power-spectrum index this result also enables a more precise measurement of the index which is now inconsistent with Harrison-Zel'dovich n=1 at 2 sigma. The best fit is around n=0.96 consistent with two of the most popular inflation models. In answer to my question Gary also noted that the octopole is now more consistent with LCDM. The quadrapole best fit is still low however examination of the complete likelihood function shows a tail to larger values such that there is a 1/10 probability of getting the observed result. Since precision is limited by cosmic variance (the quadrapole is the variance of 5 independent numbers) we can't do any better.
Laurie Leshin: First results from Stardust
Goddard Science Colloquium by Laurie Leshin (GSFC) on the preliminary (and as yet unpublished) results from Stardust. She explained why comets are interesting - they were formed far enough out in the proto-Solar nebula that they should be unprocessed material which are deflected into the inner system and hence available for study. Sample return offers the benefit that all the heavy equipment can be kept on the ground and instrument development continues after the mission is completed. Stardust successfully collected cometary dust in its aerogel and preliminary examination is underway. The most unexpected result so far is the discovery of a refractory grain which should not be present in the comet if it is unprocessed.
She finished up by describing SCIM, a Mars Scout proposal, for a sample return mission which dips into the Martian atmosphere during the dust storm season to collect particles then returns them to Earth.
She finished up by describing SCIM, a Mars Scout proposal, for a sample return mission which dips into the Martian atmosphere during the dust storm season to collect particles then returns them to Earth.
Phil Kronberg: Intergalactic CRs and mag. fields
EUD seminar by Phil Kronberg (LANL & U.Toronto) on some of his recent work on intergalactic magnetic fields observed via Faraday rotation. He is using Arecibo & DRAO interferometer to do a low surface brightness, wide-angle survey for intergalactic emission. The first field of the Coma cluster and surroundings shows emission from the same extended region seen in the X-rays.
Monday, May 22, 2006
string justification in the PS driver
Fiddled around with a hack to GRLEN to deal with the difference in character widths of for PS and PGPLOT symbols. The width ratio varies between different characters so had to give separate numbers for different categories. I only included the most common cases (a-z, A-Z, ".", "(", ")", " ", "-") but that should be close enough for most use.
The proper way to do string justification would be encode it in the PS file (using stringwidth and some tricky manipulation) however to do this the FJUST variable would have to be passed down to the GRTEXT routine and I didn't want to change the signatures of standard PGPLOT calls.
Keywords: HEAsoft, PGPLOT
The proper way to do string justification would be encode it in the PS file (using stringwidth and some tricky manipulation) however to do this the FJUST variable would have to be passed down to the GRTEXT routine and I didn't want to change the signatures of standard PGPLOT calls.
Keywords: HEAsoft, PGPLOT
Friday, May 19, 2006
more on the PS driver
Improved handling of text for the PS driver. Now pass the text bounding box values in the RBUF array for the IFUNC=31 option. These are calculated in GRTEXT where the only special case required for PS drivers is not to call GRLIN0 to actually plot the lines. This is much simpler than the previous method of setting the color to the special value of -1.
Also moved the PS driver-specific code related to the PS_VERBOSE_TEXT environment variable (which is obsolete) from GRTEXT into PSDRIV and reformatted and renamed the subroutines in PSDRIV to conform better to PGPLOT standards.
Also moved the PS driver-specific code related to the PS_VERBOSE_TEXT environment variable (which is obsolete) from GRTEXT into PSDRIV and reformatted and renamed the subroutines in PSDRIV to conform better to PGPLOT standards.
Thursday, May 18, 2006
xspec 12 start-up script
Eliminated the xspec v12 start-up script so that we just need the executable. The XSPECROOT environment variable is not used anywhere. SPECTRAL is used by routines in Global.cxx and XSGlobal.cxx where it can be replaced by HEADAS. POW_LIBRARY is set in headas-init. TCLRL_LIBRARY is used in xspec.cxx but the information it contains is available in tclreadline.h so just include that. The PGPLOT variables can all be removed once we merge the versions of pgplot under the Xspec and tcltk trees. The difference is Ben's PS driver. This uses PGPLOT_DIR for the directory containing pgprolog.ps - at the moment this is in the bin directory but should be moved to lib. PGPLOT_FONT is the font file which is an ASCII file in the Xspec tree and a binary unformatted file in the tcltk tree.
Fixed Ben's PS driver so that it is no longer necessary to set PGPLOT_PS_BBOX to MAX to avoid the chance of text being lost outside the bounding box. The trick is to have GRTEXT perform all the operations used for other devices which divide text up into line segments but not actually draw any of the lines. This ensures that the bounding box is set correctly. The
text is then written to the PostScript output. Also changed the write text option from IFUNC=30 to 31 because 30 is used for scrolling a rectangle in the X-window driver. The functions in src/grpssy.f are properly part of the PS driver so appended them to the end of psdriv.f.
Note that writing text the way we do at the moment does not conform to the pgplot architecture since it requires an explicit test for a PS device type in the routine grtext, which ought to be device-independent. The correct way to handle this is to define a new driver attribute to specify whether text needs to be split into line segments or can be written directly by the driver. grtext would then query this attribute rather than check for a specific device type.
PGPLOT_PS_BBOX should be set to MAX for Ben's PS driver otherwise text may end up lost off the edge of the bounding box.
Note that Ben's PS driver pretty clearly subverts the way that PGPLOT works. In standard drivers the text is written by drawing lines. Since PS handles text internally Ben set up a device-dependent diversion in GRTEXT to pass the text to the driver (using IFUNC=30). One consequence of this is that the bounding box variables (BBXMIN etc) are not updated for the position of the text hence the need to set PGPLOT_PS_BBOX. This ought to be fixable.
Fixed Ben's PS driver so that it is no longer necessary to set PGPLOT_PS_BBOX to MAX to avoid the chance of text being lost outside the bounding box. The trick is to have GRTEXT perform all the operations used for other devices which divide text up into line segments but not actually draw any of the lines. This ensures that the bounding box is set correctly. The
text is then written to the PostScript output. Also changed the write text option from IFUNC=30 to 31 because 30 is used for scrolling a rectangle in the X-window driver. The functions in src/grpssy.f are properly part of the PS driver so appended them to the end of psdriv.f.
Note that writing text the way we do at the moment does not conform to the pgplot architecture since it requires an explicit test for a PS device type in the routine grtext, which ought to be device-independent. The correct way to handle this is to define a new driver attribute to specify whether text needs to be split into line segments or can be written directly by the driver. grtext would then query this attribute rather than check for a specific device type.
PGPLOT_PS_BBOX should be set to MAX for Ben's PS driver otherwise text may end up lost off the edge of the bounding box.
Note that Ben's PS driver pretty clearly subverts the way that PGPLOT works. In standard drivers the text is written by drawing lines. Since PS handles text internally Ben set up a device-dependent diversion in GRTEXT to pass the text to the driver (using IFUNC=30). One consequence of this is that the bounding box variables (BBXMIN etc) are not updated for the position of the text hence the need to set PGPLOT_PS_BBOX. This ought to be fixable.
Wednesday, May 17, 2006
Suzaku XIS bad channels
Modified xselect.mdb to set the QUALITY on XIS channels 1-81 and 3290-4095 so they are ignored when the xspec command "ignore bad" is used.
Keywords: HEAsoft, Suzaku, xselect
Keywords: HEAsoft, Suzaku, xselect
mkfbin and hkbin
Modified mkfbin/hkbin so that if an event lightcurve has been extracted then the mkf/hk parameters will be binned to match the event lightcurve and the RATE will be added to the mkfbin/hkbin output file. plot mkf/hk then enables the user to plot correlations between housekeeping parameters and the event rate. Much of the code for this change has been moved out of Fortran and into a perl program (xsl_mkf_or_hk_bin).
This required a change to extractor to save the threshold used to choose whether to write out a lightcurve bin (ie minimum value of FRACEXP). This is extractor v4.65.
Added filter mkf and filter hk options as aliases for select mkf and select hk. Added save mkfbin and save hkbin options.
Set the xselect version number to 2.4 for the next HEAsoft release.
Keywords: HEAsoft, xselect, extractor
This required a change to extractor to save the threshold used to choose whether to write out a lightcurve bin (ie minimum value of FRACEXP). This is extractor v4.65.
Added filter mkf and filter hk options as aliases for select mkf and select hk. Added save mkfbin and save hkbin options.
Set the xselect version number to 2.4 for the next HEAsoft release.
Keywords: HEAsoft, xselect, extractor
Tuesday, May 09, 2006
filter time ut in xselect
Scott Porter pointed out that the filter time ut command didn't work in xselect. This was due to errors in parsing the input and in converting UT to MJD. The manual doesn't state the format required for time - it is the standard used in FITS files ie yyyy-mm-ddThh-mm-ss.sss.
Keywords : xselect, HEAsoft
Keywords : xselect, HEAsoft
Thursday, May 04, 2006
IoA models in next v12 release
Added Andy & Roderick's models kdblur, kdblur2, rdblur, and laor2 to v12 as standard models for the next release.
Keywords: HEAsoft, xspec
Keywords: HEAsoft, xspec
Wednesday, May 03, 2006
Preprints
Sutton & Wandelt present a Bayesian approach to optimal image reconstruction in radio interferometry. They use Gibbs sampling an incorporate an Occam factor.
Seljak et al. combine Ly alpha forest power spectrum results with 3-year WMAP, SN, and galaxy clustering data to constrain cosmological parameters finding the simple 6 parameter model is preferred with no running of the spectral index.
Belanger et al. claim a detection of a 22.2 min quasi-periodic modulation in the X-ray flux during the 2004 Aug 31 Sag A* flare. If this transient event was at the marginally stable orbit this implies an angular momentum parameter of 0.22.
Zucker et al. find a new Milky Way dwarf satellite galaxy at a distance of ~220 kpc using the SDSS data release 5. This discovery suggests other such objects are to be found. The same group report another dwarf galaxy.
Eisenstein et al. argue that the baryon acoustic peak can be reconstructed to correct for non-linear degradation providing significant improvements in determining the distance scale from galaxy surveys.
Bryans et al. present collisional ionization equilibrium calculations using state-of-the-art calculations from DR and RR rates.
Lawrence et al. describe the UKIRT Infrared Deep Sky Survey, a 7-year survey begun in May 05.
Begelman et al. suggest that SS433 is a ULX observed from the side with the radiative output collimated by a massive outflow from the disk at a distance of ~10% of the disk edge.
Sanders & Fabian construct a model for cluster X-ray emission including resonance scattering for several thousand lines. They find that including resonance scattering does not account for the observed dip in the central abundance however allowing for absorbing material within the inner 40 kpc of NGC4696 significantly improves the quality of the fits to the Centaurus cluster.
Forman et al. present the first results from the Chandra 500 ksec observation of M87.
Parkinson et al. apply Bayesian model selection theory to the 3-year WMAP data using the CosmoNest code and find weak evidence for a perturbation slope != 1.
Reiprich compares the 3-year WMAP results with those from the HIFLUGCS galaxy cluster sample and concludes that the new results are in much better agreement than the 1-year WMAP results.
Seljak et al. combine Ly alpha forest power spectrum results with 3-year WMAP, SN, and galaxy clustering data to constrain cosmological parameters finding the simple 6 parameter model is preferred with no running of the spectral index.
Belanger et al. claim a detection of a 22.2 min quasi-periodic modulation in the X-ray flux during the 2004 Aug 31 Sag A* flare. If this transient event was at the marginally stable orbit this implies an angular momentum parameter of 0.22.
Zucker et al. find a new Milky Way dwarf satellite galaxy at a distance of ~220 kpc using the SDSS data release 5. This discovery suggests other such objects are to be found. The same group report another dwarf galaxy.
Eisenstein et al. argue that the baryon acoustic peak can be reconstructed to correct for non-linear degradation providing significant improvements in determining the distance scale from galaxy surveys.
Bryans et al. present collisional ionization equilibrium calculations using state-of-the-art calculations from DR and RR rates.
Lawrence et al. describe the UKIRT Infrared Deep Sky Survey, a 7-year survey begun in May 05.
Begelman et al. suggest that SS433 is a ULX observed from the side with the radiative output collimated by a massive outflow from the disk at a distance of ~10% of the disk edge.
Sanders & Fabian construct a model for cluster X-ray emission including resonance scattering for several thousand lines. They find that including resonance scattering does not account for the observed dip in the central abundance however allowing for absorbing material within the inner 40 kpc of NGC4696 significantly improves the quality of the fits to the Centaurus cluster.
Forman et al. present the first results from the Chandra 500 ksec observation of M87.
Parkinson et al. apply Bayesian model selection theory to the 3-year WMAP data using the CosmoNest code and find weak evidence for a perturbation slope != 1.
Reiprich compares the 3-year WMAP results with those from the HIFLUGCS galaxy cluster sample and concludes that the new results are in much better agreement than the 1-year WMAP results.
Lieu: Soft X-ray cluster excess and SZ effect
EUD seminar by Richard Lieu from U. Alabama in Huntsville. The first half of the talk was a summary of soft X-ray observations of clusters. There are currently no confirmed observations of redshifted OVII so no definite evidence for WHIM in emission. The soft excess in the outer parts of clusters may still be thermal due to low S/N however that in the brighter regions must be non-thermal - possibly due to relativistic electrons accelerated in shocks or perhaps more exotic sources such as neutralino decay. The second and newer work was looking at WMAP data to measure the SZ effect from a sample of 30 bright, nearby clusters. The results are mixed - some clusters are clearly detected at the expected level (Coma), some are ambiguous, and some appear not to be detected at the level predicted by the X-ray data. Summing all 30 clusters and comparing with sets of randomly selected fields finds a net signal consistent with background (driven by the ~1 degree first peak in the power-spectrum). This is difficult to understand but implies some fraction of clusters do not show an SZ signal of the strength expected. Gary Hinshaw of the WMAP team confirmed that they also detect an SZ effect from Coma and that the noise level in Richard's plots is correct.
Keywords: Clusters, WMAP, SZ
Keywords: Clusters, WMAP, SZ
Thursday, April 27, 2006
diskpbb and nsatmos added to v12
Wednesday, April 26, 2006
Natarajan: Weak Lensing
UMCP astronomy colloquium by Priya Natarajan from Yale. She summarized the effects of gravitational lensing and described her work deriving the poperties of subhaloes in clusters. She fits a smooth cluster distribution then a subhalo at the position of every cluster galaxy. 10-15% of the mass of the cluster is in the subhaloes which are individually more extended than the visible light of the galaxy. She essentially does a two-parameter fit for the subhalo properties assuming that all subhaloes in the cluster have similar properties. Recent extension of this work which is in press finds evidence for tidal truncation with smaller haloes in the center of the cluster. Finally she talked about prospects for investigating dark energy by comparing the lensing of background objects of different known redshifts. In this case the details of the lens drop out and the distance ratios to the background objects can be determined and hence the cosmology.
Keywords: clusters, lensing
Keywords: clusters, lensing
Using Hera in xselect
Modified the xsl_xmm_epic_makeresp perl script so that when saving spectra in xselect and requesting a response matrix then Hera is used if SAS is not available on the local machine. I will make a similar modification to xsl_chandra_acis_makeresp when the appropriate updates are made to Hera to support it.
Keywords: xselect, HEAsoft, Hera, XMM
Keywords: xselect, HEAsoft, Hera, XMM
Tuesday, April 25, 2006
Lawrence Principe: Alchemy
Science colloquium by Larry Principe from JHU - professor in both chemistry and history of science departments. His principal argument is that alchemy is the legitimate forerunner to chemistry and alchemists have received an unfairly bad press. Many alchemists were extremely careful, observant, and dedicated experimenters. He showed pages from one alchemists lab notebook which looked similar to modern lab notebooks in the way that hypotheses were developed and tested by careful experiments. The idea of changing base metals to gold was based on a theory that all metals were composed of different amounts of philosophical mercury and philosophical sulphur. Study of alchemy is made difficult by the practice of alchemists encoding their public utterances. Fortunately, there are some private letters and notes that provide clues to the codes used. Part of Principe's research has been to decipher formulae for turning base metals into gold and then reproduce the experiments to find out what the alchemists were actually doing. He provided a recent example where the experiment produced a striking dendritic fractal structure looking very like a tree. Principe surmises that this explains the presence of trees in allegorical alchemical illustrations.
Monday, April 24, 2006
Preprints
Suebsuwong et al. discuss the effects of light bending on the reflection spectrum from disks around black holes.
Jaffe et al. explore methods for fitting templates to CMB data.
Bock et al. is the final report of a DoE/NSF/NASA task force on the future of CMB measurements providing a roadmap for precision polarization measurements.
Stanek et al. observe that star formation occurs in galaxies with low O abundances and that long GRBs appear to correlate with star formation implying that the Milky Way is unlikely to have hosted a long GRB in the last few billion years.
LaRoque et al combine Chandra X-ray and OVRO/BIMA SZ measurements of 38 massive clusters. They find consistency with an isothermal model outside the cluster core and determine the gas mass fraction within r2500. Assuming this is constant with redshift the results are consistent with the standard LCDM cosmology.
Rodriguez et al. report the detection using VLBA of a SMBH binary with a separation of only 7.3 pc.
Loeb proposes searching for evidence of planets in nearby dwarf galaxies. Since these galaxies were formed at z~10 this would argue that planets can form when the Universe was 10^3 times as dense which would contradict the anthropic argument that a low cosmological constant is required for planet formation.
Brown et al. use HST to measure the size of UB313 and find it 5% larger than Pluto. The V band albedo is 86%.
Mahajan et al. point out that if the cosmological constant is surmised to be due the zero-point energy with a suitable ultraviolet cut-off scale to get the correct value then this is testable using observations of the Casimir effect. The constraint from observation requires a zero-point value 10^12 times larger than required for the cosmological constant.
Wilson et al. discuss their plan to use Spitzer surveys to find clusters in the 1 < z < 2 'desert'.
Jaffe et al. explore methods for fitting templates to CMB data.
Bock et al. is the final report of a DoE/NSF/NASA task force on the future of CMB measurements providing a roadmap for precision polarization measurements.
Stanek et al. observe that star formation occurs in galaxies with low O abundances and that long GRBs appear to correlate with star formation implying that the Milky Way is unlikely to have hosted a long GRB in the last few billion years.
LaRoque et al combine Chandra X-ray and OVRO/BIMA SZ measurements of 38 massive clusters. They find consistency with an isothermal model outside the cluster core and determine the gas mass fraction within r2500. Assuming this is constant with redshift the results are consistent with the standard LCDM cosmology.
Rodriguez et al. report the detection using VLBA of a SMBH binary with a separation of only 7.3 pc.
Loeb proposes searching for evidence of planets in nearby dwarf galaxies. Since these galaxies were formed at z~10 this would argue that planets can form when the Universe was 10^3 times as dense which would contradict the anthropic argument that a low cosmological constant is required for planet formation.
Brown et al. use HST to measure the size of UB313 and find it 5% larger than Pluto. The V band albedo is 86%.
Mahajan et al. point out that if the cosmological constant is surmised to be due the zero-point energy with a suitable ultraviolet cut-off scale to get the correct value then this is testable using observations of the Casimir effect. The constraint from observation requires a zero-point value 10^12 times larger than required for the cosmological constant.
Wilson et al. discuss their plan to use Spitzer surveys to find clusters in the 1 < z < 2 'desert'.
Thursday, April 20, 2006
PIE and PANDA regions in extractor
Modifications to extractor region code. For PIE region fixed incorrect definition of the angle so now consistent with ds9 and other regions and fixed error that threw out all events with angle > 180 degrees. Added support for PANDA region but only for the case of one sector and one annulus. For regions in WCS coordinates correct for any CROTA in use for the input event file.
(extractor v4.64.)
Keywords : extractor, xselect, HEAsoft
(extractor v4.64.)
Keywords : extractor, xselect, HEAsoft
Wednesday, April 19, 2006
Mark Krumholz: Turbulence, Feedback, and Slow Star Formation
UMCP astronomy colloquium by Mark Krumholz, a postdoc at Princeton after doing his PhD at Berkeley. The major mystery of star formation is why it is so slow - the SFR is 100 times smaller than predicted based on free fall times. Krumholz & McKee have developed a theory where turbulence holds up star formation and the turbulence itself is produced by star formation. He showed that a fairly simple physical theory reproduces the observation results. The remaining problems are taking into account magnetic fields and explaining the 100 km/s turbulence seen in starbursts.
Keywords : star formation
Keywords : star formation
xronos window output from extractor
Fixed a bug that caused incorrect time ranges in the xronos window output (created for instance by extr curve in xselect). This was reported by Gulab Dewangan at CMU. There is still an unresolved issue if the selected region overlaps multiple chips with separate GTIs. The xronos output file contains the GTI for the final chip (in numerical order). This fix is extractor v4.63.
Keywords: xselect, extractor, HEAsoft
Keywords: xselect, extractor, HEAsoft
Tuesday, April 18, 2006
Don Lamb: Short GRBs
EUD seminar by Don Lamb. He summarized the story from last year on short GRBs then talked extensively about a HETE burst that appears short but has a photometric redshift of 1.5 (if heavily reddened) or 4.6. He suggested that there are problems with a classification scheme based on spectral hardness since results appear not to be consistent between different missions. The T90 classification also has issues because it is measured in the observed frame. If long GRBs are cosmological then the rest frame durations are much shorter (by 1+z) so the distinction between short and long is eroded. Finally he noted that the presence of a spectral lag is a good classifier of a long GRB but there are some short bursts with negligible lag but large error bars implying they are not highly structured (so lag cannot be well-measured) so these might actually be similar to long bursts.
Keywords: GRB
Keywords: GRB
Monday, April 17, 2006
Preprints
Hudson et al. analyze Chandra observations of the double jet radio source 3C 75 at the core of Abell 400 and conclude that the two AGN are a bound system from a previous merger.
Rigby et al. consider why half of X-ray selected AGN are optically dull and conclude that extranuclear dust in the host galaxy plays an important role.
Stewart describes a procedure for matched filter detection of point sources in XMM images.
Ettori & Fabian argue that He sedimentation timescales in clusters were lower in the past leading to supersolar He abundances in the cores. This has the effect of reducing the measured metal abundances in these regions.
Wilson et al. use Chandra observations to investigate the bright limbs of the cavities in Cygnus A finding a weak shock and suggesting that the jet power is going into heating the ICM.
Barkhouse et al. present a survey for X-ray detected clusters in 130 archival Chandra pointings that are part of CHAMP.
Sandage et al. summarize their 15 year program to calibrate the SN Ia Hubble diagram using HST observations of Cepheids in nearby galaxies. They derive H0 = 62.3 +/- 1.5 (stat) +/- 5.0 (syst).
Kaaret et al find a 62 +/- 2.5 day period in the X-rays from the ULX source in M82.
Egami et al. describe Spitzer observations of BCGs and note an overall trend that clusters with shorter cooling times harbor more IR luminous BCGs.
Rigby et al. consider why half of X-ray selected AGN are optically dull and conclude that extranuclear dust in the host galaxy plays an important role.
Stewart describes a procedure for matched filter detection of point sources in XMM images.
Ettori & Fabian argue that He sedimentation timescales in clusters were lower in the past leading to supersolar He abundances in the cores. This has the effect of reducing the measured metal abundances in these regions.
Wilson et al. use Chandra observations to investigate the bright limbs of the cavities in Cygnus A finding a weak shock and suggesting that the jet power is going into heating the ICM.
Barkhouse et al. present a survey for X-ray detected clusters in 130 archival Chandra pointings that are part of CHAMP.
Sandage et al. summarize their 15 year program to calibrate the SN Ia Hubble diagram using HST observations of Cepheids in nearby galaxies. They derive H0 = 62.3 +/- 1.5 (stat) +/- 5.0 (syst).
Kaaret et al find a 62 +/- 2.5 day period in the X-rays from the ULX source in M82.
Egami et al. describe Spitzer observations of BCGs and note an overall trend that clusters with shorter cooling times harbor more IR luminous BCGs.
Wednesday, April 12, 2006
Preprints
Kravtsov et al. use mock Chandra images of cluster simulations to compare X-ray estimators for the total mass and show that the new estimator Yx is remarkably good.
Werner et al. look at very hot AGB stars which are thought to have consumed their H shells exposing nucleosynthesis products.
Ascasibar & Markevitch use simulations of cluster mergers to show that cold fronts are caused by the sloshing of the cool gas in the central gravitational potential well.
Werner et al. look at very hot AGB stars which are thought to have consumed their H shells exposing nucleosynthesis products.
Ascasibar & Markevitch use simulations of cluster mergers to show that cold fronts are caused by the sloshing of the cool gas in the central gravitational potential well.
Wednesday, April 05, 2006
warning messages from znibin and inibin
Both inibin and znibin (in the NEI code cont.f) generate a warning if the response energies extend beyond the available model data. Ensured that these warning messages are written out once not every iteration. This will be in next v11 and v12 releases.
Keywords: xspec, heasoft
Keywords: xspec, heasoft
Friday, March 31, 2006
Preprints
Kunz et al. introduce Bayesian complexity to assess how many effective parameters a data set can support.
Rasia et al. use five simulated galaxy clusters to investigate systematics in the determination of the total mass using X-ray observations.
Martini et al. survey 8 low-z clusters of galaxies for X-ray AGN and conclude that cluster galaxies host an AGN with a much higher frequency than supposed from optical observations.
Davis & Hubeny describe their relativistic, non-LTE atmosphere models for accretion disks in BH binaries.
Bregman & Lloyd-Davies conclude that the soft-excesses seen in clusters using XMM are not associated with the clusters but with Galactic features.
Allen et al. demonstrate a correlation between the Bondi accretion rate and the AGN jet power using Chandra data on 9 nearby ellipticals.
Rasia et al. use five simulated galaxy clusters to investigate systematics in the determination of the total mass using X-ray observations.
Martini et al. survey 8 low-z clusters of galaxies for X-ray AGN and conclude that cluster galaxies host an AGN with a much higher frequency than supposed from optical observations.
Davis & Hubeny describe their relativistic, non-LTE atmosphere models for accretion disks in BH binaries.
Bregman & Lloyd-Davies conclude that the soft-excesses seen in clusters using XMM are not associated with the clusters but with Galactic features.
Allen et al. demonstrate a correlation between the Bondi accretion rate and the AGN jet power using Chandra data on 9 nearby ellipticals.
Wednesday, March 29, 2006
Preprints
Baker et al. present the gravitational waveforms from the final inspiral and merger of two BHs.
Simpson & Bridle consider the redshift sensitivity of various dark energy surveys.
Davis et al. fit disk-dominated black hole binary X-ray spectra with a number of different models and conclude that BHSPEC works best.
Holder demonstrates that nearly exact likelihood functions can be written down for galaxy cluster surveys.
Bregman et al. present FUSE OVI observations of three cooling flow clusters and find evidence for modest cooling flows down to temperatures of 10^5.5 K.
Begelman et al. describe a mechanism for generating massive black holes directly in the nuclei of protogalaxies without the requirement for a seed stellar mass BH.
Voigt & Fabian use Chandra observations of 12 clusters to determine the core mass profile and in 4 cases find flatter profiles than predicted by CDM. They interpret this as an underestimation of the mass in the center and suggest reasons for this to happen.
Piffaretti & Kaastra apply the effervescent heating model to XMM observations of 16 nearby clusters and find that it works in half the cases.
Simpson & Bridle consider the redshift sensitivity of various dark energy surveys.
Davis et al. fit disk-dominated black hole binary X-ray spectra with a number of different models and conclude that BHSPEC works best.
Holder demonstrates that nearly exact likelihood functions can be written down for galaxy cluster surveys.
Bregman et al. present FUSE OVI observations of three cooling flow clusters and find evidence for modest cooling flows down to temperatures of 10^5.5 K.
Begelman et al. describe a mechanism for generating massive black holes directly in the nuclei of protogalaxies without the requirement for a seed stellar mass BH.
Voigt & Fabian use Chandra observations of 12 clusters to determine the core mass profile and in 4 cases find flatter profiles than predicted by CDM. They interpret this as an underestimation of the mass in the center and suggest reasons for this to happen.
Piffaretti & Kaastra apply the effervescent heating model to XMM observations of 16 nearby clusters and find that it works in half the cases.
Tuesday, March 28, 2006
xspec 11 poisson data warning
The warning message written by stat cstat if the data are non-Poisson can be generated even with Poisson data if there are large numbers of counts/bin. This has been fixed by being more careful about numerical accuracy. Bug 11.3.2t.
Keywords: xspec, heasoft
Keywords: xspec, heasoft
Preprints
Williams et al. accumulate all the XMM calibration observations of Mkn 421 but fail to detect the absorption features seen using the Chandra LETG. However, their limits are consistent - the RGS being less sensitive due to the large number of bad detector columns, lower resolution, and fixed-pattern noise.
Linde et al. review eternal inflation and the multiverse.
Rines & Diaferio match X-ray cluster catalogs and the SDSS to examine infall patterns around 72 clusters. They demonstrate the reliability of the caustic technique for halo mass profiles.
Sereno et al. compare X-ray and SZ data for 25 clusters and estimate oblateness or prolateness. They find an excess of clusters aligned with the line of sight.
Tozzi introduces methods for determining cosmological parameters from X-ray observations of clusters.
Skinner considers the reasons for and against the use of Fresnel lens for focusing gamma- and high energy x-rays.
Nandra considers the emission sites of the narrow Fe K line cores and concludes that they are likely a mix of the inner edge of the torus and broadened emission from the accretion disk.
Garcia derives a simple approximation to the Voigt profile for use in studies of H absorption lines.
Tozzi et al. perform an X-ray spectral analysis of 321 sources in the CDFS.
Finn et al. describe the Testbed for LISA Analysis (TLA) project.
Best et al. look at radio-loud AGN heating as a regulator controlling the rate of growth of galaxies.
Linde et al. review eternal inflation and the multiverse.
Rines & Diaferio match X-ray cluster catalogs and the SDSS to examine infall patterns around 72 clusters. They demonstrate the reliability of the caustic technique for halo mass profiles.
Sereno et al. compare X-ray and SZ data for 25 clusters and estimate oblateness or prolateness. They find an excess of clusters aligned with the line of sight.
Tozzi introduces methods for determining cosmological parameters from X-ray observations of clusters.
Skinner considers the reasons for and against the use of Fresnel lens for focusing gamma- and high energy x-rays.
Nandra considers the emission sites of the narrow Fe K line cores and concludes that they are likely a mix of the inner edge of the torus and broadened emission from the accretion disk.
Garcia derives a simple approximation to the Voigt profile for use in studies of H absorption lines.
Tozzi et al. perform an X-ray spectral analysis of 321 sources in the CDFS.
Finn et al. describe the Testbed for LISA Analysis (TLA) project.
Best et al. look at radio-loud AGN heating as a regulator controlling the rate of growth of galaxies.
chkrmf
chkrmf was only checking for a MATRIX extension, not the also allowed SPECRESP MATRIX. Fixed this. Also, it was checking for required keywords in every extension - limited this to only the EBOUNDS and (SPECRESP) MATRIX extensions.
Keywords: chkrmf, heasoft
Keywords: chkrmf, heasoft
Friday, March 24, 2006
xinfix
Trapped a possible write past end of string in xinfix which occurs if the new text input by the user is longer than the input string for the routine. I think this is what caused the xspec v11 crash under Scientific Linux 4.2 reported by Glenn Morris.
Notice that there is a more general problem here with v11 in that the string containing the command input by the user which is passed down to the xspec subroutines appears to have the
length of the command string. So, any replacement prompted from the user for part of this string has to be shorter than the original or problems will occur.
Note also that I need to remember that xspec gets the xparse routines from libxantcl not libxanlib - I wasted several hours trying to work out why changes placed in libxanlib weren't showing up when running xspec.
Keywords: xspec, heasoft
Notice that there is a more general problem here with v11 in that the string containing the command input by the user which is passed down to the xspec subroutines appears to have the
length of the command string. So, any replacement prompted from the user for part of this string has to be shorter than the original or problems will occur.
Note also that I need to remember that xspec gets the xparse routines from libxantcl not libxanlib - I wasted several hours trying to work out why changes placed in libxanlib weren't showing up when running xspec.
Keywords: xspec, heasoft
xspwab
The model function routine xspwab.f used a real as a loop variable which produces an error using gfortran/g95 compilers since it is not part of the standard. Fixed this in both the v11 and v12 trees.
Keywords: xspec, heasoft
Keywords: xspec, heasoft
Thursday, March 23, 2006
xspec 11 floating overflow in ratio plots
Ryan Porter ran into a problem when doing "data ratio" plots which turned out to be a lack of protection against floating overflows when evaluating the ratio. This is fixed in 11.3.2s.
Keywords : xspec, heasoft
Keywords : xspec, heasoft
Thursday, February 23, 2006
Preprints
Humphrey et al. present Chandra results on 7 elliptical galaxies and find the data well fit by a model consisting of an NFW dark matter profile and a baryonic component following the optical light.
Ebeling et al. describe the ASMOOTH algorithm for adaptive smoothing to a constant S/N ratio.
Tozzi et al. summarize recent results from spectral analysis of sources in the CDFS.
Suyu et al. use Bayesian analysis to determine the optimal regularisation for source inversion in gravitational lensing.
Middleton et al. attempt to determine the spin of the BH in micro-quasar GRS1915+105 and conclude that jet production is likely powered by gravity not spin.
Brighenti & Mathews describe 2D gasdynamical models of jets in clusters and show that they can suppress the cooling and produce cluster temperature profiles similar to those observed.
Scarpa et al. look at the outskirts of globular clusters to see whether velocity dispersion falls off in Keplerian fashion. They find a flattening consistent with MOND or requiring DM which has not been suspected in these systems.
Ebeling et al. describe the ASMOOTH algorithm for adaptive smoothing to a constant S/N ratio.
Tozzi et al. summarize recent results from spectral analysis of sources in the CDFS.
Suyu et al. use Bayesian analysis to determine the optimal regularisation for source inversion in gravitational lensing.
Middleton et al. attempt to determine the spin of the BH in micro-quasar GRS1915+105 and conclude that jet production is likely powered by gravity not spin.
Brighenti & Mathews describe 2D gasdynamical models of jets in clusters and show that they can suppress the cooling and produce cluster temperature profiles similar to those observed.
Scarpa et al. look at the outskirts of globular clusters to see whether velocity dispersion falls off in Keplerian fashion. They find a flattening consistent with MOND or requiring DM which has not been suspected in these systems.
Wednesday, February 22, 2006
plot mkf fix
The plot mkf command in xselect fails under Linux due to a string overwrite in xsel_ftools.f. The problem was a buffer array with fixed size in a subroutine. The size of the buffer has been increased and a warning added if the new size is too small.
Keywords: xselect, heasoft
Keywords: xselect, heasoft
Saturday, February 11, 2006
filter time file in xselect
The filter time file command assumes that the extension with the START and STOP times is the first extension in the file. Now generalized this so that it looks for the GTI extension.
UPDATE: Should have also looked for an STDGTI extension since this is written by maketime. Now fixed.
Keywords: xselect, heasoft
UPDATE: Should have also looked for an STDGTI extension since this is written by maketime. Now fixed.
Keywords: xselect, heasoft
Tuesday, January 31, 2006
extractor fix for Swift UVOT lightcurves
Lightcurves from Swift UVOT event files could have TSTART=0 after time filtering. This is fixed in v4.62.
Keywords: HEAsoft, xselect, extractor
Keywords: HEAsoft, xselect, extractor
Wednesday, January 04, 2006
Preprints
Dupke & Bregman confirm their ASCA SIS Centaurus cluster velocity measurements using Chandra ACIS. They measure a velocity difference of 2.4 +/- 1 x 1e3 km/s.
Diehl & Statler present a technique for binning sparse X-ray imaging data based on weighted Voronoi tesselation which does not introduce the artefacts seen using csmooth. Open source code is available.
Bellazini et al. describe their integrated Gas Pixel Detector for X-ray polarimetry.
Rozanska et al. present warm absorber models for AGN from clouds under constant total (gas + radiation) pressure.
Brand et al. present results from the XBootes Chandra 9.3 sq deg shallow survey with deep optical follow-up. They find 47 sources that are blank-field down to R~25.5.
Bonamente et al. combine Chandra and OVRO data on 39 clusters to determine their distances using the SZ effect. They find H_0 = 77 with statistical errors of ~5 and systematic errors of ~10.
Hickox & Markevitch analyze the diffuse emission in the CDFN and CDFS and find that 79+/-8% of the 2-8 keV background has been resolved.
Peterson & Fabian review the X-ray spectroscopy of clusters of galaxies.
Daly & Djorgovski extend their model-independent approach to investigating dark energy.
Savage & Oliver present Bayesian source extraction methods.
Ford discusses efficient MCMC methods for analyzing the orbits of extrasolar planets including choice of the candidate transition probability function.
Rothman & Boughn consider whether it is possible to detect a single graviton and conclude that the answer is no when taking into account realistic physical conditions.
Diehl & Statler present a technique for binning sparse X-ray imaging data based on weighted Voronoi tesselation which does not introduce the artefacts seen using csmooth. Open source code is available.
Bellazini et al. describe their integrated Gas Pixel Detector for X-ray polarimetry.
Rozanska et al. present warm absorber models for AGN from clouds under constant total (gas + radiation) pressure.
Brand et al. present results from the XBootes Chandra 9.3 sq deg shallow survey with deep optical follow-up. They find 47 sources that are blank-field down to R~25.5.
Bonamente et al. combine Chandra and OVRO data on 39 clusters to determine their distances using the SZ effect. They find H_0 = 77 with statistical errors of ~5 and systematic errors of ~10.
Hickox & Markevitch analyze the diffuse emission in the CDFN and CDFS and find that 79+/-8% of the 2-8 keV background has been resolved.
Peterson & Fabian review the X-ray spectroscopy of clusters of galaxies.
Daly & Djorgovski extend their model-independent approach to investigating dark energy.
Savage & Oliver present Bayesian source extraction methods.
Ford discusses efficient MCMC methods for analyzing the orbits of extrasolar planets including choice of the candidate transition probability function.
Rothman & Boughn consider whether it is possible to detect a single graviton and conclude that the answer is no when taking into account realistic physical conditions.
Tuesday, January 03, 2006
addrmf and XIS rmf
Using addrmf on the x*_segc_rmf_20051021.fit XIS response files causes an error message about a failure to close the first RMF. This occurs because these files have no EXTNAME keyword for the EBOUNDS extension. The error message is misleading and unnecessary so is fixed in addrmf version 1.20.
Keywords: HEAsoft, Suzaku
Keywords: HEAsoft, Suzaku
Friday, December 23, 2005
Preprints
Page et al. find that broad-lined z~2 QSOs with X-ray absorption are embedded in submillimeter luminous starbursts implying that the X-ray absorption is unrelated to the AGN torus.
Balogh et al. compare analytical models of the ICM with recent observations and find that a range of entropy floors are required at a given halo mass.
Ho et al. use large-scale simulations to study cluster ellipticity as a cosmological probe and conclude that it provides another route to constraining cosmological parameters from large cluster samples.
Fang et al. argue that the z~0 absorbers seen in high resolution spectra of AGN are due to the hot gas associated with the Galaxy.
Sorkin republishes an old paper using Bayesian methods to derive a goodness-of-fit balancing likelihood against the number of fitting parameters.
Belczynski et al. describe the StarTrack population synthesis code for the formation and evolution of compact objects.
Dunn et al. discuss the behaviour of rising bubbles in the ICM and the precession of the 3C 84 jets in the Perseus clusters.
Balogh et al. compare analytical models of the ICM with recent observations and find that a range of entropy floors are required at a given halo mass.
Ho et al. use large-scale simulations to study cluster ellipticity as a cosmological probe and conclude that it provides another route to constraining cosmological parameters from large cluster samples.
Fang et al. argue that the z~0 absorbers seen in high resolution spectra of AGN are due to the hot gas associated with the Galaxy.
Sorkin republishes an old paper using Bayesian methods to derive a goodness-of-fit balancing likelihood against the number of fitting parameters.
Belczynski et al. describe the StarTrack population synthesis code for the formation and evolution of compact objects.
Dunn et al. discuss the behaviour of rising bubbles in the ICM and the precession of the 3C 84 jets in the Perseus clusters.
Thursday, December 22, 2005
Preprints
Crummy et al. fit XMM spectra from a sample of SyI with a relativistically-blurred photoionized disc and find this model reproduces the continuum shape, including the soft excess and many features usually interpreted as absorption, in all sources.
Fabbiano reviews X-ray source populations in galaxies.
Vernaleo & Reynolds perform 3-D hydro simulations of jets in the ICM and find that the jet energy input cannot halt the cooling flow because the energy is transmitted out of the cooling region along a low-density channel.
Sun et al. observe a 70 kpc tail behind a late-type galaxy in A3627 and use this to place constraints on turbulence in the ICM.
Jahoda et al. summarize the RXTE PCA calibration.
Hamilton et al. use archival WFPC2 imaging of 70 QSOs to find a relation between nuclear luminosity and the size and effective surface magnitude of the bulge.
Bridges et al. present a Bayesian analysis of the primordial power-law spectrum.
Baker et al. present new numerical GR techniques which enable accurate determination of GW signal from merging BHs.
Hughes motivates the widespread acceptance of BHs and describes planned tests of the hypothesis.
Nath et al. consider the production of Li6 by spallation of cosmic rays on ambient gas and show that the amount of energy generated is consistent with the extra entropy seen in the ICM.
Agueros et al. cross-correlate the RASS and SDSS looking for X-ray sources with no optical counterparts as a way of searching for isolated NS.
Cappi et al. present the results from a complete XMM survey of nearby AGN and find results broadly in agreement with the standard unified model.
Fabbiano reviews X-ray source populations in galaxies.
Vernaleo & Reynolds perform 3-D hydro simulations of jets in the ICM and find that the jet energy input cannot halt the cooling flow because the energy is transmitted out of the cooling region along a low-density channel.
Sun et al. observe a 70 kpc tail behind a late-type galaxy in A3627 and use this to place constraints on turbulence in the ICM.
Jahoda et al. summarize the RXTE PCA calibration.
Hamilton et al. use archival WFPC2 imaging of 70 QSOs to find a relation between nuclear luminosity and the size and effective surface magnitude of the bulge.
Bridges et al. present a Bayesian analysis of the primordial power-law spectrum.
Baker et al. present new numerical GR techniques which enable accurate determination of GW signal from merging BHs.
Hughes motivates the widespread acceptance of BHs and describes planned tests of the hypothesis.
Nath et al. consider the production of Li6 by spallation of cosmic rays on ambient gas and show that the amount of energy generated is consistent with the extra entropy seen in the ICM.
Agueros et al. cross-correlate the RASS and SDSS looking for X-ray sources with no optical counterparts as a way of searching for isolated NS.
Cappi et al. present the results from a complete XMM survey of nearby AGN and find results broadly in agreement with the standard unified model.
Wednesday, December 21, 2005
Preprints
Bregman shows that a claimed relationship between radio, X-ray luminosity, and BH mass in AGN is an artefact of the flux-limited sample.
Armus et al. find evidence with Spitzer for an AGN in NGC 6240 - consistent with the hard X-ray results.
Stuhlinger et al. summarize the status of XMM-Newton calibration.
Donahue et al. present Chandra entropy profiles of 9 cooling flow clusters and find the profiles are similar over a range of 3 in temperature.
Ghizzardi et al. find cold fronts in 21 out of 62 clusters searched using XMM data.
Armus et al. find evidence with Spitzer for an AGN in NGC 6240 - consistent with the hard X-ray results.
Stuhlinger et al. summarize the status of XMM-Newton calibration.
Donahue et al. present Chandra entropy profiles of 9 cooling flow clusters and find the profiles are similar over a range of 3 in temperature.
Ghizzardi et al. find cold fronts in 21 out of 62 clusters searched using XMM data.
Monday, December 19, 2005
Preprints
Badenes et al. compare the XMM and Chandra observations of Tycho with detailed hydro calculations of a variety of proposed models for SNIa and find the observations are consistent with a 1-D delayed detonation model.
Weinberg discusses multiverses and anthropic arguments.
Mathews et al. show that spherical shock waves in the ICM dissipate most of their energy near the center of the cluster causing temperatures higher than observed hence are not good candidates for solving the cooling flow problem.
Henry et al. present the results from the complete ROSAT NEP survey.
Haehnelt et al. suggest that the bright QSO HE0450 which has no detected galaxy is an SMBH ejected from its galaxy during a merger. However Merritt et al. argue against this since the kick velocity required is too large and claim that previous observations have overestimated the size of the SMBH and hence the expected luminosity of the underlying galaxy.
Bregman et al. summarize their results of OVI observations of 24 galaxies using FUSE. They find a correlation between the cooling flow rate from OVI and that from X-rays but with a large scatter. The cause of the scatter is not clear but is not obviously due to heating.
Weisskopf & Hughes give an overview of the first 6 years of Chandra observations of SNR.
Weinberg discusses multiverses and anthropic arguments.
Mathews et al. show that spherical shock waves in the ICM dissipate most of their energy near the center of the cluster causing temperatures higher than observed hence are not good candidates for solving the cooling flow problem.
Henry et al. present the results from the complete ROSAT NEP survey.
Haehnelt et al. suggest that the bright QSO HE0450 which has no detected galaxy is an SMBH ejected from its galaxy during a merger. However Merritt et al. argue against this since the kick velocity required is too large and claim that previous observations have overestimated the size of the SMBH and hence the expected luminosity of the underlying galaxy.
Bregman et al. summarize their results of OVI observations of 24 galaxies using FUSE. They find a correlation between the cooling flow rate from OVI and that from X-rays but with a large scatter. The cause of the scatter is not clear but is not obviously due to heating.
Weisskopf & Hughes give an overview of the first 6 years of Chandra observations of SNR.
Friday, December 16, 2005
Preprints
Kim et al. combine Chandra and HST data to examine the relationship between LMXBs and Globular Clusters in 6 Elliptical galaxies. They confirm that the probability of a GC containing a LMXB correlates with metallicity and also find a correlation with galactocentric distance.
Dravins et al. discuss the design of an optical instrument designed to search for variability on nanosecond scales and planned for the 100m-class OWL telescope.
Kashlinsky et al. use fluctuations in the background of a deep Spitzer observation to find evidence for Pop III stars.
Dravins et al. discuss the design of an optical instrument designed to search for variability on nanosecond scales and planned for the 100m-class OWL telescope.
Kashlinsky et al. use fluctuations in the background of a deep Spitzer observation to find evidence for Pop III stars.
Thursday, December 15, 2005
Preprints
Noble et al. describe parallelizing ISIS using the PVM.
Chevallier et al. discuss the relative roles of absorption and reflection in low energy X-ray spectra of AGN.
Belczynski et al. calculates the contribution to the LISA signal from mass transferring binaries.
Hallman et al. present calculations of H_0 based on X-ray/SZE observations of clusters assuming a universal temperature profile. This gives H_0 values closer to the standard and with smaller variance.
Blustin et al. do principle component analysis of the X-ray variability of NGC 7469.
Chevallier et al. discuss the relative roles of absorption and reflection in low energy X-ray spectra of AGN.
Belczynski et al. calculates the contribution to the LISA signal from mass transferring binaries.
Hallman et al. present calculations of H_0 based on X-ray/SZE observations of clusters assuming a universal temperature profile. This gives H_0 values closer to the standard and with smaller variance.
Blustin et al. do principle component analysis of the X-ray variability of NGC 7469.
seg fault in pexrav
Roderick Johnstone reported a seg fault in pexrav when running on a 64 bit Athlon. Craig spotted a problem on the first invocation of the model in the routine sigmabfa. There was a similar bug in pexriv, bexrav, and ntee which all use copies of this routine. At some point I need to rationalize all these programs and remove duplicated routines. Fixed as v11.3.2r and 12.2.1i & j.
Keywords: HEAsoft, xspec
Keywords: HEAsoft, xspec
Thursday, December 08, 2005
xselect manual
Updated the manual available on the web. Did the LaTeX and HTML conversion on genji in TEXT/XSELECT then copied to olegacy. Note that latex2html makes an xsel.tex top-level file. Copy that to xselect.html, remove all the contents links and tidy up. Add the contents links to node1.html. Change references in several files from xsel.tex to xselect.tex.
Keywords: HEAsoft, xselect
Keywords: HEAsoft, xselect
Thursday, December 01, 2005
Preprints
Gastaldello et al. analyze Chandra and XMM observations of poor clusters and find cool cores, a peak in temperature around 0.1 virial radii and decline. NFW model fits give concentration parameters and virial masses consistent with numerical simulations.
Done & Gierlinski show that an apparent highly relativistic line in XTE J1650 can be modelled by a relativistic line and Fe K line absorption from an outflowing disk wind - this allows the inner disk to be truncated.
Dave et al. provide an overview of current issues in galaxy formation theory.
Done & Gierlinski show that an apparent highly relativistic line in XTE J1650 can be modelled by a relativistic line and Fe K line absorption from an outflowing disk wind - this allows the inner disk to be truncated.
Dave et al. provide an overview of current issues in galaxy formation theory.
HEAsoft 6.0.4
HEAsoft 6.0.4 is now available. This is an update for Swift but also includes XSPEC v12.2.1 and
changes to cleansis and xselect/extractor for Suzaku.
changes to cleansis and xselect/extractor for Suzaku.
Wednesday, November 30, 2005
Preprints
Morganti et al. detect 1000 km/s outflows of neutral material from seven radio galaxies. This rate of up to 50 Msun/yr is comparable to outflow rates from ULIRGs.
Aharonian et al. suggest a possible associate between HESS J1825 and the pulsar wind nebula of PSR B1823 based on XMM observations of the latter.
Kauffmann et al. look at the scatter in colours and spectral line strengths of local galaxies and deduce that star formation in more compact galaxies occurs in high amplitude bursts.
Fabian et al. present first results from the 1Msec Chandra Perseus cluster observation. The pressure ripples observed in shorter observations are shown to be isothermal sound waves that can provide a heat source able to balance radiative cooling.
Chen & Pradhan calculate the ratio of the FeXVII 3s/3d lines using different electron distribution functions and surmise that some of the differences between astrophysical and laboratory measurements may be due to different plasma conditions.
Aharonian et al. suggest a possible associate between HESS J1825 and the pulsar wind nebula of PSR B1823 based on XMM observations of the latter.
Kauffmann et al. look at the scatter in colours and spectral line strengths of local galaxies and deduce that star formation in more compact galaxies occurs in high amplitude bursts.
Fabian et al. present first results from the 1Msec Chandra Perseus cluster observation. The pressure ripples observed in shorter observations are shown to be isothermal sound waves that can provide a heat source able to balance radiative cooling.
Chen & Pradhan calculate the ratio of the FeXVII 3s/3d lines using different electron distribution functions and surmise that some of the differences between astrophysical and laboratory measurements may be due to different plasma conditions.
Monday, November 28, 2005
extractor rotated box regions
My fix to the elliptical regions back in July broke the rotated box regions. The subroutines for boxes and ellipses define the rotation angle in the opposite sense. Now fixed so that both are correct (v4.61).
Keywords: HEAsoft, extractor
Keywords: HEAsoft, extractor
Thursday, November 17, 2005
xselect bug causing wrong date on lightcurve plots
The values of MJDREFI/F were not propagated everywhere correctly. I think the only consequence was that the label written at the top of the lightcurve plots gave the delta MJD not the MJD. Also did some reorganising of code and split the clear functions out into their own file (xsel_clear.f).
Keywords: HEAsoft, xselect
Keywords: HEAsoft, xselect
Monday, November 14, 2005
Preprints
Wyse & Gilmore review the Galactic populations of long-lived stars and how they can be used to investigate chemical and dynamical evolution.
Wolter et al. find three high-luminosity, narrow-line objects (ie QSO2) in the ROSAT NEP region which XMM spectra show to have no absorption above Galactic.
Revnivtsev et al. analyze RXTE scan and slew observations of the Galactic ridge X-ray emission and show that the intensity correlates with the near-infrared surface brightness and hence that the ridge emission is likely made up of many low luminosity point sources.
O'Hara et al. examine the effects of cool-cores and mergers on cluster scaling relations. They suggest that effects of cool-cores can be seen outside the cores themselves indicating that global mechanisms are at work. The evidence does not support the scenario that clusters develop cool-cores till disrupted by mergers.
Plaszczynski et al. present a fast algorithm for generating 1/f^alpha noise by filtering a white noise signal.
Liedahl & Torres provide a tutorial summary of Fe K line emission from accretion disks.
Lieu et al. claim that by comparing a WMAP and X-ray observations of a randomly-selected sample of 20 nearby clusters that the observed SZE effect is not as large as predicted.
Goad et al. describe deep XMM observations of the ULX HoII X-1 and conclude it is a high-luminosity analog of a Galactic microquasar.
Kontar et al. calculate angle-dependent Green's functions for the Compton reflection problem in Solar flares.
Wolter et al. find three high-luminosity, narrow-line objects (ie QSO2) in the ROSAT NEP region which XMM spectra show to have no absorption above Galactic.
Revnivtsev et al. analyze RXTE scan and slew observations of the Galactic ridge X-ray emission and show that the intensity correlates with the near-infrared surface brightness and hence that the ridge emission is likely made up of many low luminosity point sources.
O'Hara et al. examine the effects of cool-cores and mergers on cluster scaling relations. They suggest that effects of cool-cores can be seen outside the cores themselves indicating that global mechanisms are at work. The evidence does not support the scenario that clusters develop cool-cores till disrupted by mergers.
Plaszczynski et al. present a fast algorithm for generating 1/f^alpha noise by filtering a white noise signal.
Liedahl & Torres provide a tutorial summary of Fe K line emission from accretion disks.
Lieu et al. claim that by comparing a WMAP and X-ray observations of a randomly-selected sample of 20 nearby clusters that the observed SZE effect is not as large as predicted.
Goad et al. describe deep XMM observations of the ULX HoII X-1 and conclude it is a high-luminosity analog of a Galactic microquasar.
Kontar et al. calculate angle-dependent Green's functions for the Compton reflection problem in Solar flares.
Thursday, November 10, 2005
new models added to xspec v12
I've added Martin Still's dust extinction models and Slava Zavlin and George Pavlov's NS atmosphere model to the xspec v12 for the forthcoming release. When the release is out I will retire them from the additional models webpage.
Keywords: HEAsoft, xspec
Keywords: HEAsoft, xspec
Sunday, November 06, 2005
PLT command lengths in xspec v11
Bill ran into a problem running the Swift processing script under Hera. He needed to create a gif file in xspec v11 in a remote directory with a long pathname. This overran the string length available in xspec. Modified xspec to allow longer PLT command names and device names. I also had to modify PLT to increase the allowed device name length. The limit now is 80 characters which seems to be imposed by the PGPLOT code. I've not tried to track down where that is set.
Saturday, November 05, 2005
Theatre: Cuttin' Up
Last night went to Arena stage for the first night preview of world premiere. Cuttin' Up is written and directed by Charles Randolph-Wright adapted from the book of the same name by Craig Marberry, who visited African-American barbershops around the US collecting the stories told there. The barbershop and the church are the two places African-American men can gather and talk and a rich history has built up around the former. The play presents that history as stories told by the three barbers and their customers, all of whom are played five actors in a wide variety of wigs. Dramatic tension is supplied by the conflict between the owner and the man he wants to be his successor, but who has a history of leaving cities and marriages. I found the story suprisingly effective since it is little more than a rack on which to hang a wonderful collection of vignettes and songs. Among the former my favourite was a competition between a Baptist and an AME preacher. The Baptist played by Bill Grimmette finished with a peroration on the importance of the barbershop delivered in full sermon style.
The show was almost stolen by Marva Hicks playing all the female characters from hot youngster, through mother from the projects, R&B singer, outrageously-dressed Texan female barber, to the 75-year-old mother of one of the barbers. She and many other cast members pulled off some very fast changes, both of clothes and hair styles. The other star of the show is the costume department with their wonderful collection of wigs all the way up to a 2-ft wide Afro.
With an almost full house for first-night preview and a standing ovation at the end this one will be a hit for Arena.
The show was almost stolen by Marva Hicks playing all the female characters from hot youngster, through mother from the projects, R&B singer, outrageously-dressed Texan female barber, to the 75-year-old mother of one of the barbers. She and many other cast members pulled off some very fast changes, both of clothes and hair styles. The other star of the show is the costume department with their wonderful collection of wigs all the way up to a 2-ft wide Afro.
With an almost full house for first-night preview and a standing ovation at the end this one will be a hit for Arena.
Thursday, November 03, 2005
chkrmf fix
Fixed infinite loop which arises if one of the extensions doesn't have its EXTNAME set. Also replaced explicit loop through extensions with calls to go to named extensions. Note that this program and its peers (chkarf, chkpha) could do with an overhaul and check for consistency with the current standard.
Keywords: HEAsoft
Keywords: HEAsoft
minor extractor bug with multiple event files
There was an error in the code comparing TLMIN/MAX values for WMAP columns when reading multiple event files. This produced a spurious warning message about different sizes for XCOLH and YCOLH columns. Fixed in v4.60.
Keywords: HEAsoft, extractor
Keywords: HEAsoft, extractor
Monday, October 31, 2005
Preprints
Li-Xin Li & Paczynski present a new procedure for smoothing GRB lightcurves and calculating the variability. This leads to a very tight correlation between variability and peak luminosity.
Muanwong et al. use hydro simulations to investigate the evolution of X-ray cluster scaling relations under different mechanisms to increasing the entropy. They find indications that early, widespread pre-heating is favoured.
Dotti et al. study the inspiral of binary black holes inside a massive circum-nuclear disk.
Markwardt et al. present the first BAT serendipitous source catalog. The final catalog is expected to contain > 200 AGN and reach a limiting flux of 1e-11 in the 14-195 keV band.
Brewer & Lewis use Bayesian Inference and MCMC simulations on the strong gravitational lens problem.
Regimbau & Pacheco estimate the gravitational background from magnetars and note that it could mask a contribution from the early Universe.
Muanwong et al. use hydro simulations to investigate the evolution of X-ray cluster scaling relations under different mechanisms to increasing the entropy. They find indications that early, widespread pre-heating is favoured.
Dotti et al. study the inspiral of binary black holes inside a massive circum-nuclear disk.
Markwardt et al. present the first BAT serendipitous source catalog. The final catalog is expected to contain > 200 AGN and reach a limiting flux of 1e-11 in the 14-195 keV band.
Brewer & Lewis use Bayesian Inference and MCMC simulations on the strong gravitational lens problem.
Regimbau & Pacheco estimate the gravitational background from magnetars and note that it could mask a contribution from the early Universe.
Thursday, October 27, 2005
Preprints
Dewangan et al. report the detection of a low frequency break and a QPO in the ULX M82 X-1. This is characteristic of an XRB in a high or intermediate state. The BH mass is estimated at 50-260 Solar masses.
Peterson et al. take a sample of nearby well-studied AGN and artificially redshift them to z=0.3 then consider what would be seen in a Chandra survey. They argue that these objects look like the "normal" and "optically-bright X-ray-faint" galaxy populations suggesting that these objects may contribute to the hard X-ray background.
Peterson et al. take a sample of nearby well-studied AGN and artificially redshift them to z=0.3 then consider what would be seen in a Chandra survey. They argue that these objects look like the "normal" and "optically-bright X-ray-faint" galaxy populations suggesting that these objects may contribute to the hard X-ray background.
Preprints
Cappi et al. present the results of an XMM survey of the nearest 27 Seyfert galaxies. The results are broadly in agreement with unification models with Sy 2 absorption columns ranging from 1e20 to 1e25 cm^-2.
Zhao et al. apply Bekenstein's relativistic version of MOND to gravitationa lens observations. They find a range of acceleration scales are required in violation of the assumption that this is a universal constant.
Lu & Love present a method for diverting an Earth-threatening asteroid using a spacecraft that hovers near the object. This eliminates the anchoring and rotation problems of a spacecraft pushing on the asteroid.
Diehl & Statler analyze archival Chandra observations of 30 early-type galaxies and find a relation between the X-ray temperature, half-light radius, and mean surface brightness. The width of this fundamental plane (0.07dex) is nearly identical to that of the stellar (optical) fundamental plane.
Atoyan et al. argue that HESS J1303-631, a bright, extended TeV source invisible at other wavelengths is the remnant of a long gamma-ray burst.
Stroeer et al. discuss what can be learned from LISA detections of interacting double WD binaries.
Seward et al. find no evidence for a thermal shell around the Crab Nebula from Chandra observations. The background consists of a dust scattering shell and mirror scattering.
The shell has L_X < 1e34 erg/s.
Watson et al. present the Swift X-ray spectrum and lightcurve of the z=6.29 GRB. In the first few minutes of the burst the apparent luminosity was 1e5-1e6 times that of the brightest high-z quasars.
Zhao et al. apply Bekenstein's relativistic version of MOND to gravitationa lens observations. They find a range of acceleration scales are required in violation of the assumption that this is a universal constant.
Lu & Love present a method for diverting an Earth-threatening asteroid using a spacecraft that hovers near the object. This eliminates the anchoring and rotation problems of a spacecraft pushing on the asteroid.
Diehl & Statler analyze archival Chandra observations of 30 early-type galaxies and find a relation between the X-ray temperature, half-light radius, and mean surface brightness. The width of this fundamental plane (0.07dex) is nearly identical to that of the stellar (optical) fundamental plane.
Atoyan et al. argue that HESS J1303-631, a bright, extended TeV source invisible at other wavelengths is the remnant of a long gamma-ray burst.
Stroeer et al. discuss what can be learned from LISA detections of interacting double WD binaries.
Seward et al. find no evidence for a thermal shell around the Crab Nebula from Chandra observations. The background consists of a dust scattering shell and mirror scattering.
The shell has L_X < 1e34 erg/s.
Watson et al. present the Swift X-ray spectrum and lightcurve of the z=6.29 GRB. In the first few minutes of the burst the apparent luminosity was 1e5-1e6 times that of the brightest high-z quasars.
Sunday, October 23, 2005
xselect bug causing deletion of event files !
There is a bug in xselect which causes an event file to be deleted when running a make obscat for a mission with > 8 instrument types. This is triggered for the Suzaku HXD. I've fixed this by increasing the allowed number of types to 20 and putting in a trap to catch any future case of more than this. Also added DETNAM to the HXD displayed values so that the user can see which files in the catalog are PIN and which GSO.
Keywords: xselect, Suzaku
Keywords: xselect, Suzaku
Saturday, October 22, 2005
CHANNEL column in type II files
At the request of the GLAST GBM folks removed the requirement for a CHANNEL column in type II spectral files. Having the CHANNEL column vector in every row is inefficient when there are many rows and the information is not required as long as data from all spectral channels are included in the COUNTS or RATE vector. Available as v11.3.2p and also shortly in v12. Need to update the standard memo appropriately.
Keywords: HEAsoft, xspec, GLAST
Keywords: HEAsoft, xspec, GLAST
Wednesday, October 19, 2005
bug in extractor when combining 3x3 and 5x5 XIS files
Aya Bamba reported an obscure bug when running extract event in xselect. If both 3x3 and 5x5 event files are in use and the 5x5 is first then the resulting event file loses the events from the 3x3 file. Reproducing her problem showed that the events from the 3x3 file were in the output file but their TIME column had zero values. This was due to a bug in extractor which occurred if the first file had fewer columns than the second - the values from the extra columns would be lost even if these columns were matched in name with those in the first file ie if the differences between the files consisted of some additional columns added in the middle of the row. This
particular case has probably never arisen before. Fixed as extractor v4.59.
Keywords: HEAsoft, xselect, extractor, Suzaku
particular case has probably never arisen before. Fixed as extractor v4.59.
Keywords: HEAsoft, xselect, extractor, Suzaku
Thursday, October 13, 2005
extractor and region files
Extractor seg faults when fed a region file with a comment marker (#) included after a region descriptor. This can happen if a color is specified for the region using ds9.
Keywords: heasoft, extractor
Keywords: heasoft, extractor
Monday, October 10, 2005
grppha and grouping=0
Fixed grppha so that individual bad channels have grouping=1 not grouping=0. This conforms with the standard and ensures that xspec v12 doesn't issue a warning. This should not change any other behaviour.
Keywords: HEAsoft
Keywords: HEAsoft
Tuesday, October 04, 2005
xselect/extractor updates
A couple of minor updates. In extractor trapped the case of the grade column having no TLMIN/MAX. Previously this generated an obscure error when running. Now arbitrarily assumes that grade varies between 0 and 25. This should be fine as long as the actual grade is within this range. Also updated xselect.par so that the default mission is Suzaku rather than ASCA (about time!).
Keywords: HEAsoft, xselect, extractor
Keywords: HEAsoft, xselect, extractor
Monday, October 03, 2005
Suzaku XIS sky images
The current v0.1 processed files have sky image coordinates wrong due to an error in xiscoord. To get correct positions either multiply the image CDELT1 and CDELT2 by -1 or in the event files set TCDLT10 = 0.0002895 and TCDLT11 = -0.0002895.
Keywords : Suzaku
Keywords : Suzaku
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