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X-ray emission mechanisms of LINERs

Stefanie Komossa·Dieter Breitschwerdt·Hans Boehringer·Janek Meerschweinchen
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Abstract

We present here an analysis of the X-ray properties of a sample of LINER galaxies observed with the ROSAT PSPC and HRI instruments. A spatial analysis shows that the bulk of the X-ray emission is consistent with arising from a point source; some extended emission appears at weak emission levels. The X-ray spectra are formally best described by a powerlaw with photon index Gamma_x ~ -2 or thermal emission from a Raymond-Smith plasma with highly subsolar abundances (Z < 0.1). Several emission mechanisms that might contribute to the observed X-ray spectra are discussed. In particular, we take the very subsolar abundances derived from Raymond-Smith fits as an indication of a more complex emission mechanism, like the presence of a second hard component or plasma out of collisional-ionization equilibrium.

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Stefanie Komossa, Dieter Breitschwerdt, Hans Boehringer, Janek Meerschweinchen. 1999-07-07. X-ray emission mechanisms of LINERs. https://doi.org/10.1023/a%3A1002617101356

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