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arXiv · 1203.6352

No Evidence for Intermediate-Mass Black Holes in Globular Clusters: Strong Constraints from the JVLA

Jay Strader·Laura Chomiuk·Thomas Maccarone·James Miller-Jones·Anil Seth·Craig Heinke·Gregory Sivakoff
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Abstract

With a goal of searching for accreting intermediate-mass black holes (IMBHs), we report the results of ultra-deep Jansky VLA radio continuum observations of the cores of three Galactic globular clusters: M15, M19, and M22. We reach rms noise levels of 1.5-2.1 uJy/beam at an average frequency of 6 GHz. No sources are observed at the center of any of the clusters. For a conservative set of assumptions about the properties of the accretion, we set 3-sigma upper limits on IMBHs from 360-980 M_sun. These limits are among the most stringent obtained for any globular cluster. They add to a growing body of work that suggests either (a) IMBHs ~> 1000 M_sun are rare in globular clusters, or (b) when present, IMBHs accrete in an extraordinarily inefficient manner.

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Jay Strader, Laura Chomiuk, Thomas Maccarone, James Miller-Jones, Anil Seth, Craig Heinke, Gregory Sivakoff. 2012-03-28. No Evidence for Intermediate-Mass Black Holes in Globular Clusters: Strong Constraints from the JVLA. https://doi.org/10.1088/2041-8205%2F750%2F2%2Fl27

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