HEASARC Staff Scientist Position - Applications are now being accepted for a Staff Scientist with significant experience and interest in the technical aspects of astrophysics research, to work in the High Energy Astrophysics Science Archive Research Center (HEASARC) at NASA Goddard Space Flight Center (GSFC) in Greenbelt, MD. Refer to the AAS Job register for full details.

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Next: polpow: Power-law dependent polarization Up: Additive Model Components Previous: polconst: Constant polarization


pollin: Linearly dependent polarization

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

$\displaystyle A(E) = {\tt A1} + (E-1.0) \times {\tt Aslope}$
$\displaystyle \psi(E) = {\tt psi1} + (E-1.0) \times {\tt psislope}$

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

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Last modified: Friday, 23-Aug-2024 13:20:40 EDT

HEASARC Staff Scientist Position - Applications are now being accepted for a Staff Scientist with significant experience and interest in the technical aspects of astrophysics research, to work in the High Energy Astrophysics Science Archive Research Center (HEASARC) at NASA Goddard Space Flight Center (GSFC) in Greenbelt, MD. Refer to the AAS Job register for full details.