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X-ray and Optical Filaments in M87

William B. Sparks·Megan Donahue·Andres Jordan·Laura Ferrarese·Patrick Cote
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Abstract

We compare a very deep X-ray image of M87, at the center of the Virgo Cluster, to high-quality optical images of the low excitation emission-line gas in the same region. There are striking coincidences of detail between the two. We explore the possiblity that this represents a thermal interaction between hot gas at 10^7 K and warm gas at 10^4 K. We find two temperatures are present in the X-ray gas, with the lower more prevelant in the vicinity of the optical filaments. Electron conduction from the hot phase to the cooler one provides a quantitatively acceptable energy source for the optical filaments, and we show additionally that it can do so for the brightest X-ray cluster, Perseus. If operative, conduction in the presence of gas-rich galaxy mergers, may explain the presence of "cool cores" in clusters of galaxies.

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William B. Sparks, Megan Donahue, Andres Jordan, Laura Ferrarese, Patrick Cote. 2004-02-09. X-ray and Optical Filaments in M87. https://doi.org/10.1086/383189

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