Constant density ionised disc models

These large table model files, provided by David Ballantyne (drb@ast.cam.ac.uk) calculate the reflection spectrum from an ionized slab of an input power-law. The models include lines and edges from Fe, O, Si, Mg, and C. They are valid over the energy range 1eV -> 100 keV. The problem that prevented convergence on some parts of the grid has been fixed in these tables.

  • References :
    Ross & Fabian, 1993, MNRAS, 261, 74
    Ballantyne, Iwasawa & Fabian, 2001, MNRAS, 323, 506

  • Model parameters are :

    • The LOG of the ionisation 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= 15, and the flux was varied to change the ionisation parameter.
      Valid range: 1.0 -> 6.0. Stepsize: 0.05 (in the log)

    • The photon index of incident power-law, Gamma
      Valid range: 1.5 -> 3.0. Stepsize: 0.05

    • Reflection fraction, R.
      Model=Incident+R*Reflected
      This describes how strong the reflection component is in the model spectrum. It is not necessarily related to the subtending solid angle of the slab, as that depends on geometric assumptions.
      Valid range: 0.0 -> 2.0. Stepsize: 0.05

    • Normalization = related to photon flux at the detector This does not have 1/d^2 dilution included, so expect a very small number for this (about 1e-27) (the models predictions are in photons/s per emitting area)

    • Redshift

  • Invoke using the atable command and the fits file of the grid.

  • The available models are :


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

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Last modified: Thursday, 16-Sep-2004 20:21:53 EDT