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High Resolution Soft X-ray Spectroscopy of M87 with the Reflection Grating Spectrometers on XMM-Newton

I. Sakelliou·J. R. Peterson·T. Tamura·F. B. S. Paerels·J. S. Kaastra·E. Belsole·H. Boehringer·G. Branduardi-Raymont·C. Ferrigno·J. W. den Herder·J. Kennea·R. F. Mushotzky·W. T. Vestrand·D. M. Worrall
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Abstract

We present high-resolution X-ray spectroscopic observations of M87 with the Reflection Grating Spectrometers on XMM-Newton. We detect strong K-shell line emission from N, O, Ne, Mg, some emission from He-like Si, a fully resolved set of Fe L-shell emission spectra, and some emission from C. The angular intensity distributions of the strong emission lines are detectably resolved on scales (15-160) arcsec. The gas in the inner arcmin of M87 has a multi-phase structure, as indicated by the similarity of the emission line profiles of Fe L shell ions with widely separated ionization potentials. The global Fe L spectrum is approximately consistent with an isothermal plasma at kT_e ~ 1.8 keV, in addition to a component with a temperature distribution appropriate to an isobaric cooling flow, but with a minimum temperature cutoff of kT_min ~ 600 eV. The behaviour of this cooling-flow component is qualitatively similar to what is seen in other cooling flow clusters. Finally, we do not find any strong evidence for a spatial variation in abundances due to resonance scattering redistribution in the inner arcminute of the core.

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I. Sakelliou, J. R. Peterson, T. Tamura, F. B. S. Paerels, J. S. Kaastra, E. Belsole, H. Boehringer, G. Branduardi-Raymont, C. Ferrigno, J. W. den Herder, J. Kennea, R. F. Mushotzky, W. T. Vestrand, D. M. Worrall. 2002-06-14. High Resolution Soft X-ray Spectroscopy of M87 with the Reflection Grating Spectrometers on XMM-Newton. https://doi.org/10.1051/0004-6361%3A20020900

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