Reflionx - reflection by a constant density illuminated atmosphere

The emergent ("reflected") spectrum is calculated for an optically-thick atmosphere (such as the surface of an accretion disk) of constant density illuminated by radiation with a power-law spectrum. The illumination has a high-energy exponential cutoff with e-folding energy fixed at 300 keV and a sharp lower energy cutoff at 0.1 keV. The reflected spectrum is calculated over the range 1 eV to 1 MeV. Non-LTE calculations provide temperature and ionization structures for the gas that are consistent with the local radiation fields. In addition to fully-ionized species, the following ions are included in the calculations: C III-VI, N III-VII, O III-VIII, Ne III-X, Mg III-XII, Si IV-XIV, S IV-XVI, and Fe VI-XXVI.

Note that the physical situation is similar to that in the "constant density ionised disc models". The calculations in the new model include a much broader range of elements and energetically-important ionization states.

  • References :
    Ross & Fabian (2005), MNRAS, 358, 211
    Ross, Fabian & Young (1999), MNRAS, 306, 461
    See also

  • Model parameters are :

    • Fe/solar = abundance of iron relative to solar value (range 0.1 to 10.0). Abundances of other elements are fixed at solar values (Morrison & McCammon 1983, ApJ, 270, 119).
    • Gamma = photon index for illuminating power-law spectrum (range 1.0 to 3.0).
    • Xi = ionization parameter (range 30 to 1.0e4 erg cm/s). Here Xi=4*pi*F/n, where F is the total illuminating flux and n is the hydrogen number density.
    • Redshift
    • Norm = normalization of reflected spectrum.

  • Invoke using the atable{"reflionx.mod"} command after downloading reflionx.mod.gz and gunzipping.

    Note that this table model file replaced an older version (reflion.mod.gz) which used an illuminating spectrum extending down to 1 eV. This is probably not correct for steep input spectra so the newer file is preferred.

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

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