Shimura and Takahara accretion disk model

This is the X-ray accretion disk spectral model by Shimura and Takahara 1995, ApJ, 445, 780. The code was developed by Toshiya Shimura (, and the FITS file was made by Ken Ebisawa ( There are two parameters, mass of the central object (solar mass unit), and accretion rate in the unit of Ledd/c2, where Ledd is the Eddington luminosity and c is the light velocity (the same unit in Shimura and Takahara 1995). Normalization is (10kpc/d)^2*cos i, where d is the distance, i is the disk inclination angle.

Note, this disk spectral calculation is based on the formalism by Novikov and Thorne (1973), in which Riffert and Herold (1995, ApJ, 450, 508) later found a mistake. Effect of this mistake on the disk spectra is considered to be negligible, though.

  • Invoke using the atable{"ST95.fits"} command after downloading ST95.fits.

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

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