Friday, March 31, 2006


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.

Wednesday, March 29, 2006


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.

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


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.


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

Friday, March 24, 2006


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


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

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