This multiplicative model applies a polarization with a linear dependence on energy. The factor applied depends on which Stokes parameter the spectrum is for. The Stokes parameter is determined using an XFLTnnnn keyword with values ``Stokes:0'', ``Stokes:1'', or ``Stokes:2'', for I, Q, U, respectively.
The fraction and angle are determined by
The parameters are :
par1 | A1, the polarization fraction at 1 keV |
par2 | Aslope, the polarization fraction slope |
par3 | psi1, the polarization angle at 1 keV (degrees) |
par4 | psislope, the polarization angle slope |