A Massive, Cooling-Flow-Induced Starburst in the Core of a Highly Luminous Galaxy Cluster
Abstract
In the cores of some galaxy clusters the hot intracluster plasma is dense enough that it should cool radiatively in the cluster's lifetime, leading to continuous "cooling flows" of gas sinking towards the cluster center, yet no such cooling flow has been observed. The low observed star formation rates and cool gas masses for these "cool core" clusters suggest that much of the cooling must be offset by astrophysical feedback to prevent the formation of a runaway cooling flow. Here we report X-ray, optical, and infrared observations of the galaxy cluster SPT-CLJ2344-4243 at z = 0.596. These observations reveal an exceptionally luminous (L_2-10 keV = 8.2 x 10^45 erg/s) galaxy cluster which hosts an extremely strong cooling flow (dM/dt = 3820 +/- 530 Msun/yr). Further, the central galaxy in this cluster appears to be experiencing a massive starburst (740 +/- 160 Msun/yr), which suggests that the feedback source responsible for preventing runaway cooling in nearby cool core clusters may not yet be fully established in SPT-CLJ2344-4243. This large star formation rate implies that a significant fraction of the stars in the central galaxy of this cluster may form via accretion of the intracluster medium, rather than the current picture of central galaxies assembling entirely via mergers.
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Cite
@article{arxiv.1208.2962,
title = {A Massive, Cooling-Flow-Induced Starburst in the Core of a Highly Luminous Galaxy Cluster},
author = {M. McDonald and M. Bayliss and B. A. Benson and R. J. Foley and J. Ruel and P. Sullivan and S. Veilleux and K. A. Aird and M. L. N. Ashby and M. Bautz and G. Bazin and L. E. Bleem and M. Brodwin and J. E. Carlstrom and C. L. Chang and H. M. Cho and A. Clocchiatti and T. M. Crawford and A. T. Crites and T. de Haan and S. Desai and M. A. Dobbs and J. P. Dudley and E. Egami and W. R. Forman and G. P. Garmire and E. M. George and M. D. Gladders and A. H. Gonzalez and N. W. Halverson and N. L. Harrington and F. W. High and G. P. Holder and W. L. Holzapfel and S. Hoover and J. D. Hrubes and C. Jones and M. Joy and R. Keisler and L. Knox and A. T. Lee and E. M. Leitch and J. Lieu and M. Lueker and D. Luong-Van and A. Mantz and D. P. Marrone and J. J. McMahon and J. Mehl and S. S. Meyer and E. D. Miller and L. Mocanu and J. J. Mohr and T. E. Montroy and S. S. Murray and T. Natoli and S. Padin and T. Plagge and C. Pryke and T. D. Rawle and C. L. Reichardt and A. Rest and M. Rex and J. E. Ruhl and B. R. Saliwanchik and A. Saro and J. T. Sayre and K. K. Schaffer and L. Shaw and E. Shirokoff and R. Simcoe and J. Song and H. G. Spieler and B. Stalder and Z. Staniszewski and A. A. Stark and K. Story and C. W. Stubbs and R. Suhada and A. van Engelen and K. Vanderlinde and J. D. Vieira and A. Vikhlinin and R. Williamson and O. Zahn and A. Zenteno},
journal= {arXiv preprint arXiv:1208.2962},
year = {2015}
}
Comments
11 pages, 3 figures, 1 table. Supplemental material contains 15 additional pages. Published in Nature