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ASCA Guest Observer Facility



Image Credit: Tanaka et al., Copyright: Nature, 375, 659, 1995
Image generated by Dr. Paul Nandra NASA/GSFC

The line profile of iron K-alpha from MCG-6-30-15 observed by the ASCA satellite (Tanaka et al, 1995, Nature, 375, 659). The emission line is extremely broad, with a width indicating velocities of order one-third of the speed of light. There is a marked asymmetry towards energies lower than the rest-energy of the emission line (6.4 keV). This asymmetry is most likely caused by gravitational and relativistic-Doppler shifts near the black hole at the center of the galaxy. The solid line shows the model profile expected from a disk of matter orbiting the hole, extending between 3 and 10 Schwarzschild radii.
Get the Color Postscript image. of this spectrum.

For more information see:
"On the dependence of iron K-line profiles with luminosity in Active Galactic Nuclei"; Nandra, K., Mushotzky, R.F., George, I.M., Turner, T.J. , Yaqoob, T. 1997, ApJ, 488, L91

There is also a simulation of a black hole that may explain this result.

This file was last modified on Wednesday, 16-Feb-2005 12:04:47 EST
Curator: Michael Arida (SP Sys);
HEASARC Guest Observer Facility

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This file was last modified on Wednesday, 16-Feb-2005 12:04:47 EST

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