Skip to main content

The archive browser Xamin is down due to overload. Our team is working to restore the service. The classic Browse interface is still operational.

next up previous contents
Next: posm: positronium continuum Up: Additive Model Components Previous: pollin: Linearly dependent polarization   Contents


polpow: Power-law dependent polarization

This multiplicative model applies a polarization with a power-law 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

$\displaystyle A(E) = {\tt Anorm} \times E^{-{\tt Aindex}}$
$\displaystyle \psi(E) = {\tt psinorm} \times E^{-{\tt psiindex}}$

The parameters are :

par1 Anorm, the polarization fraction at 1 keV
par2 Aindex, the polarization fraction index
par3 psinorm, the polarization angle at 1 keV (degrees)
par4 psiindex, the polarization angle index