[1203.6352] No Evidence for Intermediate-Mass Black Holes in Globular Clusters: Strong Constraints from the JVLA

Authors: Jay Strader, Laura Chomiuk, Thomas Maccarone, James Miller-Jones, Anil Seth, Craig Heinke, Gregory Sivakoff

Date: 28 Mar 2012

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.

abs pdf

Apr 05, 2012

1203.6352 (/preprints)
2012-04-05, 09:28 [edit]


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