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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coplrefl: reflection of a power-law (with a variable high-energy cutoff) from a constant density ionized accretion disk

This table model provides the reflection spectrum from a constant density disk illuminated by a hard power-law with a variable high-energy cutoff (defined as in the highecut model). The models have been used to fit data from X-ray pulsars. They were computed using the same version of the Ross reflection code as the AGN constant density ionized disk models and the blackbody reflection models.

Full details of the calculations can be found in Ballantyne, D.R, et al., 2012, ApJ Letters, in press (arXiv:1202.2311).

The author is more than happy to collaborate with observers to produce grids if the one below is not appropriate for a certain observation/dataset.

Model parameters are:

  • the LOG of the ionization parameter of the slab: Xi = 4 PI*F/n, where F=incident flux (in ergs/s/cm**2) and n=hydrogen number density of slab (cm**{-3}).

    The models were calculated with log n= 19, and the flux was varied to change the ionization parameter. Valid range: 1.5 -> 4.0 (actually, 3.977). Stepsize: 0.5 (in the log)

  • Gamma (photon index). Valid range: 0.5 -> 1.5. Stepsize: 0.1

  • E_cut (cutoff energy). Valid range: 5 -> 30 keV. Stepsize: 5 keV

  • E_fold (e-folding energy). Valid range: 5 -> 30 keV. Stepsize: 5 keV

  • Redshift

  • Normalization. As the model predicts flux per emitting area, this is a very small number (about 1e-30 or less).

The table model only includes the reflection spectra, so the illuminating spectrum must be defined separately in the model (typically as powerlaw*highecut).

The table model file can be downloaded as coplrefl.fits.

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

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Last modified: Tuesday, 14-Feb-2012 13:53:36 EST

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.