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OATS-DAUT SEMINAR
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Speaker:
Mark Voit (Michigan State Univ.)
Title:
Mysteries of Galaxy Cluster Cores
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Abstract: The cores of galaxy clusters have defied
interpretation for almost three decades. Early X-ray observations
seemed to imply that the intergalactic gas in a cluster should be
cooling and condensing within the central galaxy. Over the course of
several billion years, that process of cooling and condensation should
have formed an enormous number of stars, far larger than the numbers
of stars that are currently observed in the central galaxies of
clusters. For some reason, gas is not cooling and condensing at the
predicted rate. Recent observations have suggested that active
galactic nuclei at the centers of galaxy clusters are supplying the
energy that halts condensation, but the way in which that happens
remains mysterious. I will discuss some of the latest ideas about
what is happening in cluster cores and their cosmological
implications.
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