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arXiv · 0910.0853

Spectacular X-ray tails, intracluster star formation and ULXs in A3627

M. Sun·M. Donahue·E. Roediger·P. E. J. Nulsen·G. M. Voit·C. Sarazin·W. Forman·C. Jones
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Abstract

We present the discovery of spectacular double X-ray tails associated with ESO137-001 and a possibly heated X-ray tail associated with ESO137-002, both late-type galaxies in the closest rich cluster Abell 3627. A deep Chandra observation of ESO137-001 allows us for the first time to examine the spatial and spectral properties of such X-ray tails in detail. Besides the known bright tail that extends to ~ 80 kpc from ESO137-001, a fainter and narrower secondary tail with a similar length was surprisingly revealed. There is little temperature variation along both tails. We also identified six X-ray point sources as candidates of intracluster ULXs with L(0.3-10 keV) of up to 2.5x10^40 erg s^-1. Gemini spectra of intracluster HII regions downstream of ESO137-001 are also presented, as well as the velocity map of these HII regions that shows the imprint of ESO137-001's disk rotation. For the first time, we unambiguously know that active star formation can happen in the cold ISM stripped by ICM ram pressure and it may contribute a significant amount of the intracluster light. We also report the discovery of a 40 kpc X-ray tail of another late-type galaxy in A3627, ESO137-002. Its X-ray tail seems hot, ~ 2 keV (compared to ~ 0.8 keV for ESO137-001's tails). We conclude that the high pressure environment around these two galaxies is important for their bright X-ray tails and the intracluster star formation.

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M. Sun, M. Donahue, E. Roediger, P. E. J. Nulsen, G. M. Voit, C. Sarazin, W. Forman, C. Jones. 2009-12-02. Spectacular X-ray tails, intracluster star formation and ULXs in A3627. https://doi.org/10.1088/0004-637x%2F708%2F2%2F946

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