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arXiv · 1904.08406

Revealing the differences in the SMBH accretion rate distributions of starburst and non-starburst galaxies

L. P. Grimmett·J. R. Mullaney·S. Jin·E. Bernhard·E. Daddi·K. Walters
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Abstract

We infer and compare the specific X-ray luminosity distributions for a sample of massive (i.e. $\log_{10} (M*/M\odot) > 10.5$) galaxies split according to their far-infrared-derived star-forming properties (i.e., starburst and non-starburst) and redshift. We model each distribution as a power-law with an upper and lower turnover, and adopt a maximum likelihood method to include information from non-detections in the form of upper limits. When we use our inferred distributions to calculate the ratios of high to low sLx AGN (corresponding to above and below $0.1\lambda_{\text{Edd}}$, respectively) we find that starbursts have significantly higher proportions of high sLx AGN compared to their non-starburst counterparts. These findings help explain the increase in average X-ray luminosity in bins of increasing SFR reported by previous studies.

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L. P. Grimmett, J. R. Mullaney, S. Jin, E. Bernhard, E. Daddi, K. Walters. 2019-04-16. Revealing the differences in the SMBH accretion rate distributions of starburst and non-starburst galaxies. https://doi.org/10.1093/mnras%2Fstz1558

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