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To find and download HEASARC data in the cloud, you can use astroquery.heasarc or download our new tool, hark.

The HEASARC and NuSTAR teams are greatly saddened by the sudden passing of Katja Pottschmidt. Most recently Katja was the lead scientist for the NuSTAR Guest Observer Facility (GOF), a role she had supported for many years. During her science career she worked on many other high energy astrophysics missions and played an integral role in advancing our knowledge of the universe. She was a wonderful colleague and friend and will be keenly missed by all who knew her.

HEASoft and XSPEC are now available as conda packages. See details ....


Model for partial covering of partially ionised absorbing material.

This model is now in the Xspec release and this page is superceded by the Xspec manual

This uses a grid of XSTAR photionised absorption models (calculated assuming a microturbulent velocity of 200km/s) for the absorption, then assumes that this only covers some fraction f of the source, while the remaining (1-f) of the spectrum is seen directly. This is the model used by Reeves et al (2008) 'On why the iron K-shell absorption in AGN is not the signature of the local warm-hot intergalactic medium', and may also be more generally applicable to the spectral complexity seen in Narrow Line Seyfert 1 AGN (Miller et al 2007, A&A, 463, 13).

This is a multiplicative model. The parameters are

par1 = column density in units of 1022 cm^-2
par2 = log(xi) where xi=L/nr^2
par3 = covering fraction f
par4 = redshift

To install this model download the source code (zxipcf.f), model datafile (zxipcf_mtable.fits), and the model parameter description file (zxipcf_lmodel.dat). zxipcf will look for its model datafile in the current directory or the directory specified in xspec by using xset ZXIPCF_DIR directory.

Questions and comments? Contact Chris Done: chris.done(at)durham.ac.uk