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arXiv · 1603.00348

Where Are Most of the Globular Clusters in Today's Universe?

William E. Harris
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Abstract

The total number of globular clusters (GCs) in a galaxy rises continuously with the galaxy luminosity L, while the relative number of galaxies decreases with L following the Schechter function. The product of these two very nonlinear functions gives the relative number of GCs contained by all galaxies at a given L. It is shown that GCs, in this universal sense, are most commonly found in galaxies within a narrow range around $L_{\star}$. In addition, blue (metal-poor) GCs outnumber the red (metal-richer) ones globally by 4 to 1 when all galaxies are added, pointing to the conclusion that the earliest stages of galaxy formation were especially favorable to forming massive, dense star clusters.

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William E. Harris. 2016-03-01. Where Are Most of the Globular Clusters in Today's Universe?. https://doi.org/10.3847/0004-6256/151/4/102

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