_version_ 1866914184019574784
author Silverman, John
Li, Junyao
Ding, Xuheng
Onoue, Masafusa
Strauss, Michael
Matsuoka, Yoshiki
Izumi, Takuma
Jahnke, Knud
Treu, Tommaso
Volonteri, Marta
Phillips, Camryn
Andika, Irham
Aoki, Kentaro
Arita, Junya
Baba, Shunsuke
Bosman, Sarah
Eilers, Anna-Christina
Fan, Xiaohui
Fujimoto, Seiji
Habouzit, Melanie
Haiman, Zoltan
Imanishi, Masatoshi
Inayoshi, Kohei
Iwasawa, Kazushi
Kashikawa, Nobunari
Kawaguchi, Toshihiro
Lee, Chien-Hsiu
Lupi, Alessandro
Nagao, Tohru
Schindler, Jan-Torge
Schramm, Malte
Shimasaku, Kazuhiro
Toba, Yoshiki
Trakhtenbrot, Benny
Umehata, Hideki
Vestergaard, Marianne
Walter, Fabian
Wang, Feige
Yang, Jinyi
author_facet Silverman, John
Li, Junyao
Ding, Xuheng
Onoue, Masafusa
Strauss, Michael
Matsuoka, Yoshiki
Izumi, Takuma
Jahnke, Knud
Treu, Tommaso
Volonteri, Marta
Phillips, Camryn
Andika, Irham
Aoki, Kentaro
Arita, Junya
Baba, Shunsuke
Bosman, Sarah
Eilers, Anna-Christina
Fan, Xiaohui
Fujimoto, Seiji
Habouzit, Melanie
Haiman, Zoltan
Imanishi, Masatoshi
Inayoshi, Kohei
Iwasawa, Kazushi
Kashikawa, Nobunari
Kawaguchi, Toshihiro
Lee, Chien-Hsiu
Lupi, Alessandro
Nagao, Tohru
Schindler, Jan-Torge
Schramm, Malte
Shimasaku, Kazuhiro
Toba, Yoshiki
Trakhtenbrot, Benny
Umehata, Hideki
Vestergaard, Marianne
Walter, Fabian
Wang, Feige
Yang, Jinyi
contents The relation between the masses of supermassive black holes (SMBHs) and their host galaxies encodes information on their mode of growth, especially at the earliest epochs. The James Webb Space Telescope (JWST) has opened such investigations by detecting the host galaxies of AGN and more luminous quasars within the first billion years of the universe (z > 6). Here, we evaluate the relation between the mass of SMBHs and the total stellar mass of their host galaxies using a sample of nine quasars at 6.18 < z < 6.4 from the Subaru High-z Exploration of Low-luminosity Quasars (SHELLQs) survey with NIRCam and NIRSpec observations. We find that the observed location of these quasars in the SMBH-galaxy mass plane (log M_BH/Msun ~ 8-9; log M_*/Msun ~ 9.5-11) is consistent with a non-evolving intrinsic mass relation with dispersion (0.80_{-0.28}^{+0.23} dex) higher than the local value (~0.3-0.4 dex) of their more massive descendants. Our analysis is based on a forward model of systematics and includes a consideration of the impact of selection effects and measurement uncertainties with an assumption on the slope of the mass relation. While degeneracies between parameters persist, the best-fit solution has a reasonable AGN fraction (2.3%) of galaxies at z ~ 6 with an actively growing UV-unobscured black hole. In particular, models with a substantially higher normalisation in M_BH would require an unrealistically low intrinsic dispersion (~0.22 dex). Consequently, our results predict a large population of AGNs at lower black hole masses, as are now just starting to be discovered in focused efforts with JWST.
format Preprint
id arxiv_https___arxiv_org_abs_2507_23066
institution arXiv
publishDate 2025
record_format arxiv
spellingShingle SHELLQs-JWST perspective on the intrinsic mass relation between supermassive black holes and their host galaxies at z > 6
Silverman, John
Li, Junyao
Ding, Xuheng
Onoue, Masafusa
Strauss, Michael
Matsuoka, Yoshiki
Izumi, Takuma
Jahnke, Knud
Treu, Tommaso
Volonteri, Marta
Phillips, Camryn
Andika, Irham
Aoki, Kentaro
Arita, Junya
Baba, Shunsuke
Bosman, Sarah
Eilers, Anna-Christina
Fan, Xiaohui
Fujimoto, Seiji
Habouzit, Melanie
Haiman, Zoltan
Imanishi, Masatoshi
Inayoshi, Kohei
Iwasawa, Kazushi
Kashikawa, Nobunari
Kawaguchi, Toshihiro
Lee, Chien-Hsiu
Lupi, Alessandro
Nagao, Tohru
Schindler, Jan-Torge
Schramm, Malte
Shimasaku, Kazuhiro
Toba, Yoshiki
Trakhtenbrot, Benny
Umehata, Hideki
Vestergaard, Marianne
Walter, Fabian
Wang, Feige
Yang, Jinyi
Astrophysics of Galaxies
The relation between the masses of supermassive black holes (SMBHs) and their host galaxies encodes information on their mode of growth, especially at the earliest epochs. The James Webb Space Telescope (JWST) has opened such investigations by detecting the host galaxies of AGN and more luminous quasars within the first billion years of the universe (z > 6). Here, we evaluate the relation between the mass of SMBHs and the total stellar mass of their host galaxies using a sample of nine quasars at 6.18 < z < 6.4 from the Subaru High-z Exploration of Low-luminosity Quasars (SHELLQs) survey with NIRCam and NIRSpec observations. We find that the observed location of these quasars in the SMBH-galaxy mass plane (log M_BH/Msun ~ 8-9; log M_*/Msun ~ 9.5-11) is consistent with a non-evolving intrinsic mass relation with dispersion (0.80_{-0.28}^{+0.23} dex) higher than the local value (~0.3-0.4 dex) of their more massive descendants. Our analysis is based on a forward model of systematics and includes a consideration of the impact of selection effects and measurement uncertainties with an assumption on the slope of the mass relation. While degeneracies between parameters persist, the best-fit solution has a reasonable AGN fraction (2.3%) of galaxies at z ~ 6 with an actively growing UV-unobscured black hole. In particular, models with a substantially higher normalisation in M_BH would require an unrealistically low intrinsic dispersion (~0.22 dex). Consequently, our results predict a large population of AGNs at lower black hole masses, as are now just starting to be discovered in focused efforts with JWST.
title SHELLQs-JWST perspective on the intrinsic mass relation between supermassive black holes and their host galaxies at z > 6
topic Astrophysics of Galaxies
url https://arxiv.org/abs/2507.23066