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This model is now in the Xspec release and this page is superceded by the Xspec manual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