An Entropy Threshold for Strong Hα and Radio Emission in the Cores of Galaxy Clusters
- 1 August 2008
- journal article
- Published by American Astronomical Society in The Astrophysical Journal
- Vol. 683 (2), L107-L110
- https://doi.org/10.1086/591665
Abstract
Our Chandra X-ray Observatory archival study of intracluster entropy in a sample of 222 galaxy clusters shows that H-alpha and radio emission from the brightest cluster galaxy are much more pronounced when the cluster's core gas entropy is < 30 keV cm^2. The prevalence of H-alpha emission below this threshold indicates that it marks a dichotomy between clusters that can harbor multiphase gas and star formation in their cores and those that cannot. The fact that strong central radio emission also appears below this boundary suggests that AGN feedback turns on when the intracluster medium starts to condense, strengthening the case for AGN feedback as the mechanism that limits star formation in the Universe's most luminous galaxies.Comment: Submitted to ApJ LetterKeywords
This publication has 38 references indexed in Scilit:
- Breaking the hierarchy of galaxy formationMonthly Notices of the Royal Astronomical Society, 2006
- The extended H -emitting filaments surrounding NGC 4696, the central galaxy of the Centaurus clusterMonthly Notices of the Royal Astronomical Society, 2005
- A Systematic Study of Radio‐induced X‐Ray Cavities in Clusters, Groups, and GalaxiesThe Astrophysical Journal, 2004
- The ROSAT Brightest Cluster Sample -- III. Optical spectra of the central cluster galaxiesMonthly Notices of the Royal Astronomical Society, 1999
- SUMSS: A Wide-Field Radio Imaging Survey of the Southern Sky. I. Science Goals, Survey Design, and InstrumentationThe Astronomical Journal, 1999
- Spectral gradients in central cluster galaxies: further evidence of star formation in cooling flowsMonthly Notices of the Royal Astronomical Society, 1998
- The NRAO VLA Sky SurveyThe Astronomical Journal, 1998
- The FIRST Survey: Faint Images of the Radio Sky at Twenty CentimetersThe Astrophysical Journal, 1995
- The radio properties of cD galaxies in Abell clusters. I - an X-ray selected sampleThe Astronomical Journal, 1990
- Radio emission in the directions of cD and related galaxies in poor clusters. III - VLA observations at 20 CMThe Astronomical Journal, 1981