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arXiv · 2409.06772

Broad-Line AGN at 3.5<z<6: The Black Hole Mass Function and a Connection with Little Red Dots

Anthony J. Taylor·Steven L. Finkelstein·Dale D. Kocevski·Junehyoung Jeon·Volker Bromm·Ricardo O. Amorin·Pablo Arrabal Haro·Bren E. Backhaus·Micaela B. Bagley·Eduardo Bañados·Rachana Bhatawdekar·Madisyn Brooks·Antonello Calabro·Oscar A. Chavez Ortiz·Yingjie Cheng·Nikko J. Cleri·Justin W. Cole·Kelcey Davis·Mark Dickinson·Callum Donnan·James S. Dunlop·Richard S. Ellis·Vital Fernandez·Adriano Fontana·Seiji Fujimoto·Mauro Giavalisco·Andrea Grazian·Jingsong Guo·Nimish P. Hathi·Benne W. Holwerda·Michaela Hirschmann·Kohei Inayoshi·Jeyhan S. Kartaltepe·Yana Khusanova·Anton M. Koekemoer·Vasily Kokorev·Rebecca L. Larson·Gene C. K. Leung·Ray A. Lucas·Derek J. McLeod·Lorenzo Napolitano·Masafusa Onoue·Fabio Pacucci·Casey Papovich·Pablo G. Pérez-González·Nor Pirzkal·Rachel S. Somerville·Jonathan R. Trump·Stephen M. Wilkins·L. Y. Aaron Yung·Haowen Zhang
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Abstract

We present a sample of 50 H-alpha detected broad-line active galactic nuclei (BLAGN) at redshifts 3.5 0), independent of the contributions of emission lines to the broadband photometry. We construct the black hole (BH) mass function at 3.5<z<6 after computing robust observational and line detection completeness corrections. This BH mass function shows broad agreement with both recent JWST/NIRSpec and JWST/NIRCam WFSS based BH mass functions, though we extend these earlier results to log(M(BH)/M(sun)) < 7. The derived BH mass function is consistent with a variety of theoretical models, indicating that the observed abundance of black holes in the early universe is not discrepant with physically-motivated predictions. The BH mass function shape resembles a largely featureless power-law, suggesting that any signature from black-hole seeding has been lost by redshift z~5-6. Finally, we compute the BLAGN UV luminosity function and find good agreement with JWST-detected BLAGN samples from recent works, finding that BLAGN hosts constitute <10% of the total observed UV luminosity at all but the brightest luminosities.

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Anthony J. Taylor, Steven L. Finkelstein, Dale D. Kocevski, Junehyoung Jeon, Volker Bromm, Ricardo O. Amorin, Pablo Arrabal Haro, Bren E. Backhaus, Micaela B. Bagley, Eduardo Bañados, Rachana Bhatawdekar, Madisyn Brooks, Antonello Calabro, Oscar A. Chavez Ortiz, Yingjie Cheng, Nikko J. Cleri, Justin W. Cole, Kelcey Davis, Mark Dickinson, Callum Donnan, James S. Dunlop, Richard S. Ellis, Vital Fernandez, Adriano Fontana, Seiji Fujimoto, Mauro Giavalisco, Andrea Grazian, Jingsong Guo, Nimish P. Hathi, Benne W. Holwerda, Michaela Hirschmann, Kohei Inayoshi, Jeyhan S. Kartaltepe, Yana Khusanova, Anton M. Koekemoer, Vasily Kokorev, Rebecca L. Larson, Gene C. K. Leung, Ray A. Lucas, Derek J. McLeod, Lorenzo Napolitano, Masafusa Onoue, Fabio Pacucci, Casey Papovich, Pablo G. Pérez-González, Nor Pirzkal, Rachel S. Somerville, Jonathan R. Trump, Stephen M. Wilkins, L. Y. Aaron Yung, Haowen Zhang. 2024-09-10. Broad-Line AGN at 3.5<z<6: The Black Hole Mass Function and a Connection with Little Red Dots. https://arxiv.org/abs/2409.06772

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