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arXiv · 1510.01733

Detecting Direct Collapse Black Holes: making the case for CR7

Bhaskar Agarwal·Jarrett L. Johnson·Erik Zackrisson·Ivo Labbe·Frank C. van den Bosch·Priyamvada Natarajan·Sadegh Khochfar
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Abstract

We propose that one of the sources in the recently detected system CR7 by Sobral et al. (2015) through spectro-photometric measurements at $z = 6.6$ harbors a direct collapse blackhole (DCBH). We argue that the LW radiation field required for direct collapse in source A is provided by sources B and C. By tracing the LW production history and star formation rate over cosmic time for the halo hosting CR7 in a $Λ$CDM universe, we demonstrate that a DCBH could have formed at $z\sim 20$. The spectrum of source A is well fit by nebular emission from primordial gas around a BH with MBH $\sim 4.4 \times 10^6 \ \rm M_{\odot}$ accreting at a 40 % of the Eddington rate, which strongly supports our interpretation of the data. Combining these lines of evidence, we argue that CR7 might well be the first DCBH candidate.

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Bhaskar Agarwal, Jarrett L. Johnson, Erik Zackrisson, Ivo Labbe, Frank C. van den Bosch, Priyamvada Natarajan, Sadegh Khochfar. 2016-09-01. Detecting Direct Collapse Black Holes: making the case for CR7. https://doi.org/10.1093/mnras%2Fstw1173

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