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arXiv · 1806.00259

The MAVERIC Survey: Still No Evidence for Accreting Intermediate-mass Black Holes in Globular Clusters

Evangelia Tremou·Jay Strader·Laura Chomiuk·Laura Shishkovsky·Thomas J. Maccarone·James C. A. Miller-Jones·Vlad Tudor·Craig O. Heinke·Gregory R. Sivakoff·Anil C. Seth·Eva Noyola
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Abstract

We present the results of an ultra-deep, comprehensive radio continuum survey for the accretion signatures of intermediate-mass black holes in globular clusters. The sample, imaged with the Karl G.~Jansky Very Large Array and the Australia Telescope Compact Array, comprises 50 Galactic globular clusters. No compelling evidence for an intermediate-mass black hole is found in any cluster in our sample. In order to achieve the highest sensitivity to low-level emission, we also present the results of an overall stack of our sample, as well as various subsamples, also finding non-detections. These results strengthen the idea that intermediate-mass black holes with masses $\gtrsim 1000 M_{\odot}$ are rare or absent in globular clusters.

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Evangelia Tremou, Jay Strader, Laura Chomiuk, Laura Shishkovsky, Thomas J. Maccarone, James C. A. Miller-Jones, Vlad Tudor, Craig O. Heinke, Gregory R. Sivakoff, Anil C. Seth, Eva Noyola. 2018-06-01. The MAVERIC Survey: Still No Evidence for Accreting Intermediate-mass Black Holes in Globular Clusters. https://doi.org/10.3847/1538-4357%2Faac9b9

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