Monday, September 25, 2006


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.

Monday, September 18, 2006


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.

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 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


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.

Monday, September 11, 2006


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.

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