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Arxiv: JWST CEERS & JADES Active Galaxies at z = 4-7 Violate the Local M_\bullet-M_\star Relation at >3σ: Implications for Low-Mass Black Holes and Seeding Models Published: 8/23/2023 9:00:00 PM Updated: 10/9/2023 6:54:33 PM

Paper abstract: JWST is revolutionizing our understanding of the high-z Universe byexpanding the black hole horizon, looking farther and to smaller masses, andrevealing the stellar light of their hosts. By examining JWST galaxies atz=4-7 that host H\alpha-detected black holes, we investigate (i) thehigh-z M_\bullet-M_* relation and (ii) the black hole massdistribution, especially in its low-mass range (M_\bullet <~ 10^{6.5}M_\odot). With a detailed statistical analysis, our findings conclusivelyreveal a high-z M_\bullet-M_* relation that deviates at >3\sigmaconfidence level from the local relation. The high-z relation is:\log(M_\bullet/M_\odot) = -2.43^{+0.83}_{-0.83} + 1.06^{+0.09}_{-0.09}\log(M_*/M_\odot). Black holes are overmassive by ~ 10-100\timescompared to their low-z counterparts in galactic hosts of the same stellarmass. This fact is not due to a selection effect in surveys. Moreover, ouranalysis predicts the possibility of detecting in high-z JWST surveys5-15\times more black holes with M_\bullet <~ 10^{6.5} M_\odot, and10-30\times more with M_\bullet <~ 10^{8.5} M_\odot, compared tolocal relation's predictions. The lighter black holes preferentially occupygalaxies with a stellar mass of ~ 10^{7.5}-10^8 M_\odot. We have yet todetect these sources because (i) they may be inactive (duty cycles 1\%-10\%),(ii) the host overshines the AGN, or (iii) the AGN is obscured and notimmediately recognizable by line diagnostics. A search of low-mass black holesin existing JWST surveys will further test the M_\bullet-M_* relation.Current JWST fields represent a treasure trove of black hole systems at z =4-7; their detection will provide crucial insights into their early evolutionand co-evolution with their galactic hosts.