xscat: dust scattering

This model calculates the X-ray scattering cross section of a population of dust grains as a function of energy, given a specific dust grain position and an extraction region. As the grain position gets closer to the source of the X-rays for a constant extraction region, the cross section drops as more X-rays remain within the extraction circle. For constant dust grain position, the cross section decreases with increasing extraction region size because more photons remain within it.

A detailed description of the model can be found in Smith, Valencic & Corrales (2016).

The model parameters are as follows.

par1 = $NH$	interstellar hydrogen column density ($10^{22}$ cm$^{-2}$).
par2 = $Xpos$	the relative position of the dust along the line of sight. This varies between 0 for dust at the observer and 1 for dust at the source.
par3 = $Rext$	the radius of the circular extraction region (arcsec).
par4 = $DustModel$	the dust model used (see Smith et al. 2016). The model options are 1=MRN, 2=WD, and 3=ZDABAS.

The third and fourth parameters must be frozen.

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Last modified: Wednesday, 12-Mar-2025 17:05:25 EDT