Skip to main content

To find and download HEASARC data in the cloud, you can use astroquery.heasarc or download our new tool, hark.

The HEASARC and NuSTAR teams are greatly saddened by the sudden passing of Katja Pottschmidt. Most recently Katja was the lead scientist for the NuSTAR Guest Observer Facility (GOF), a role she had supported for many years. During her science career she worked on many other high energy astrophysics missions and played an integral role in advancing our knowledge of the universe. She was a wonderful colleague and friend and will be keenly missed by all who knew her.

HEASoft and XSPEC are now available as conda packages. See details ....


Constant density ionised disc models

These large table model files, provided by David Ballantyne (ballanty -at- cita.utoronto.ca) calculate the reflection spectrum from an ionized slab of an input power-law. The models include lines and edges from Fe, O, Si, Mg, N and C. They are valid over the energy range 1eV -> 100 keV. Note that these models to not include any relativistic blurring due to proximity to a black hole. These should be added using a separate convolution model if relevant.

These table model files are an updated version with N vi-vii added, increased spectral resolution, and the ability to test variations in the Fe abundance. The old version of this page is available.

See also the reflion model.

  • 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 -> 5.0. Stepsize: 0.05 (in the log)

    • The photon index of incident power-law, Gamma
      Valid range: 1.5 -> 2.5. 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 -> 5.0. 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 :

    Fe AbundanceFilenameReflection Fraction
    0.5 Solartable_0.5solarFe_nobb_r0-5.fits0.0-5.0 in steps of 0.05
    0.5 Solartable_0.5solarFe_nobb_no_r.fitsInfinite
    1.0 Solartable_solarFe_nobb_r0-5.fits0.0-5.0 in steps of 0.05
    1.0 Solartable_solarFe_nobb_no_r.fitsInfinite
    2.0 Solartable_2xsolarFe_nobb_r0-5.fits0.0-5.0 in steps of 0.05
    2.0 Solartable_2xsolarFe_nobb_no_r.fitsInfinite
    3.0 Solartable_3xsolarFe_nobb_r0-5.fits0.0-5.0 in steps of 0.05
    3.0 Solartable_3xsolarFe_nobb_no_r.fitsInfinite