Model for partially absorbing material with large velocity shear.

NOTE: This model is now in the Xspec release and this page is superceded by the Xspec manual

This is the 'swind1' model to fit the soft excess in AGN by partially ionised absorbing material with large velocity shear. It approximates this by using XSTAR kn5 photoionisation absorption model grids (calculated assuming a microturbulent velocity of 100km/s), and then convolving this with Gaussian smearing. This is the model used by Gierlinski & Done 2006, Sobolewska & Done 2006 and Done et al 2006. It is an update (uses a newer version of XSTAR) of the original model of Gierlinski & Done 2004.

This is a multiplicative model. The parameters are

par1 = column density in units of 10^22 cm^-2
par2 = log(xi) where xi=L/nr^2
par3 = sigma : Gaussian sigma for velocity smearing in units of v/c
par4 = redshift

To install this model download the source code (swind1.f), model datafile (swind1_mtable.fits), and the model parameter description file (swind1_lmodel.dat, updated 7/19/07 with modified limits on the column parameter). You should edit swind1.f and replace the string $LMODDIR with the full path to the directory in which you want to store swind1_mtable.fits. Note: To use this model with XSPEC12, you'll need to have first updated it to patch version 12.3.0af or later. The latest patchfile is available here.

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

Keith Arnaud, Lab. for High Energy Astrophysics, NASA/Goddard Space Flight Center

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Last modified: Tuesday, 14-Feb-2023 16:42:05 EST

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