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Register a new userTrinity I: Self-Consistently Modeling the Dark Matter Halo-Galaxy-Supermassive Black Hole Connection from $z=0-10$
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We present Trinity, a flexible empirical model that self-consistently infers the statistical connection between dark matter haloes, galaxies, and supermassive black holes (SMBHs). Trinity is constrained by galaxy observables from $0 < z < 10$ (galaxies stellar mass functions, specific and cosmic SFRs, quenched fractions, and UV luminosity functions) and SMBH observables from $0 < z < 6.5$ (quasar luminosity functions, quasar probability distribution functions, active black hole mass functions, local SMBH mass-bulge mass relations, and the observed SMBH mass distributions of high redshift bright quasars). The model includes full treatment of observational systematics (e.g., AGN obscuration and errors in stellar masses). From these data, Trinity infers the average SMBH mass, SMBH accretion rate, merger rate, and Eddington ratio distribution as functions of halo mass, galaxy stellar mass, and redshift. Key findings include: 1) the normalization of the SMBH mass-bulge mass relation increases only mildly from $z=0$ to $z=3$, but decreases more strongly from $z=3$ to $z=10$; 2) The AGN radiative$+$kinetic efficiency is $sim$0.04-0.07, and does not show significant redshift dependence given the existing data constraints; 3) AGNs show downsizing, i.e., the Eddington ratios of more massive SMBHs start to decrease earlier than those of lower-mass objects; 4) The average ratio between average SMBH accretion rate and SFR is $sim10^{-3}$ for low-mass galaxies, which are primarily star-forming. This ratio increases to $sim10^{-1}$ for the most massive haloes below $zsim1$, where star formation is quenched but SMBHs continue to accrete.
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We present a method to flexibly and self-consistently determine individual galaxies star formation rates (SFRs) from their host haloes potential well depths, assembly histories, and redshifts. The method is constrained by galaxies observed stellar mass functions, SFRs (specific and cosmic), quenched fractions, UV luminosity functions, UV-SM relations, IRX-UV relations, auto- and cross-correlation functions (including quenched and star-forming subsamples), and quenching dependence on environment; each observable is reproduced over the full redshift range available, up to 0<z<10. Key findings include: galaxy assembly correlates strongly with halo assembly; quenching at z>1 correlates strongly with halo mass; quenched fractions at fixed halo mass decrease with increasing redshift; massive quenched galaxies reside in higher-mass haloes than star-forming galaxies at fixed galaxy mass; star-forming and quenched galaxies star formation histories at fixed mass differ most at z<0.5; satellites have large scatter in quenching timescales after infall, and have modestly higher quenched fractions than central galaxies; Planck cosmologies result in up to 0.3 dex lower stellar mass-halo mass ratios at early times; and, nonetheless, stellar mass-halo mass ratios rise at z>5. Also presented are revised stellar mass-halo mass relations for all, quenched, star-forming, central, and satellite galaxies; the dependence of star formation histories on halo mass, stellar mass, and galaxy SSFR; quenched fractions and quenching timescale distributions for satellites; and predictions for higher-redshift galaxy correlation functions and weak lensing surface densities. The public data release (DR1) includes the massively parallel (>10^5 cores) implementation (the UniverseMachine), the newly compiled and remeasured observational data, derived galaxy formation constraints, and mock catalogues including lightcones.
Observational studies of nearby galaxies have demonstrated correlations between the mass of the central supermassive black holes (BHs) and properties of the host galaxies, notably the stellar bulge mass or central stellar velocity dispersion. Motivated by these correlations, the theoretical paradigm has emerged, in which BHs and bulges co-evolve. However, this picture was challenged by observational and theoretical studies, which hinted that the fundamental connection may be between BHs and dark matter halos, and not necessarily with their host galaxies. Based on a study of 3130 elliptical galaxies $-$ selected from the Sloan Digital and ROSAT All Sky Surveys $-$ we demonstrate that the central stellar velocity dispersion exhibits a significantly tighter correlation with the total gravitating mass, traced by the X-ray luminosity of the hot gas, than with the stellar mass. This hints that the central stellar velocity dispersion, and hence the central gravitational potential, may be the fundamental property of elliptical galaxies that is most tightly connected to the larger-scale dark matter halo. Furthermore, using the central stellar velocity dispersion as a surrogate for the BH mass, we find that in elliptical galaxies the inferred BH mass and inferred total gravitating mass within the virial radius (or within five effective radii) can be expressed as $M_{rm{BH}} propto M_{rm tot}^{1.6^{+0.6}_{-0.4}} $ (or $M_{rm{BH}} propto M_{rm{5r_{eff}}}^{1.8^{+0.7}_{-0.6}}$). These results are consistent with a picture in which the BH mass is directly set by the central stellar velocity dispersion, which, in turn, is determined by the total gravitating mass of the system.
There is mounting evidence for the coevolution of galaxies and their embedded massive black holes (MBHs) in a hierarchical structure formation paradigm. To tackle the nonlinear processes of galaxy-MBH interaction, we describe a self-consistent numerical framework which incorporates both galaxies and MBHs. The high-resolution adaptive mesh refinement (AMR) code Enzo is modified to model the formation and feedback of molecular clouds at their characteristic scale of 15.2 pc and the accretion of gas onto a MBH. Two major channels of MBH feedback, radiative feedback (X-ray photons followed through full 3D adaptive ray tracing) and mechanical feedback (bipolar jets resolved in high-resolution AMR), are employed. We investigate the coevolution of a 9.2e11 Msun galactic halo and its 1e5 Msun embedded MBH at redshift 3 in a cosmological LCDM simulation. The MBH feedback heats the surrounding ISM up to 1e6 K through photoionization and Compton heating and locally suppresses star formation in the galactic inner core. The feedback considerably changes the stellar distribution there. This new channel of feedback from a slowly growing MBH is particularly interesting because it is only locally dominant, and does not require the heating of gas globally on the disk. The MBH also self-regulates its growth by keeping the surrounding ISM hot for an extended period of time.
I present a simple phenomenological model for the observed linear scaling of the stellar mass in old globular clusters (GCs) with $z=0$ halo mass in which the stellar mass in GCs scales linearly with progenitor halo mass at $z=6$ above a minimum halo mass for GC formation. This model reproduces the observed $M_{rm GCs}-M_{rm halo}$ relation at $z=0$ and results in a prediction for the minimum halo mass at $z=6$ required for hosting one GC: $M_{rm min}(z=6)=1.07 times 10^9,M_{odot}$. Translated to $z=0$, the mean threshold mass is $M_{rm halo}(z=0) approx 2times 10^{10},M_{odot}$. I explore the observability of GCs in the reionization era and their contribution to cosmic reionization, both of which depend sensitively on the (unknown) ratio of GC birth mass to present-day stellar mass, $xi$. Based on current detections of $z gtrsim 6$ objects with $M_{1500} < -17$, values of $xi > 10$ are strongly disfavored; this, in turn, has potentially important implications for GC formation scenarios. Even for low values of $xi$, some observed high-$z$ galaxies may actually be GCs, complicating estimates of reionization-era galaxy ultraviolet luminosity functions and constraints on dark matter models. GCs are likely important reionization sources if $5 lesssim xi lesssim 10$. I also explore predictions for the fraction of accreted versus in situ GCs in the local Universe and for descendants of systems at the halo mass threshold of GC formation (dwarf galaxies). An appealing feature of the model presented here is the ability to make predictions for GC properties based solely on dark matter halo merger trees.
Recently, simple metrics of spherically symmetric black hole in dark matter halo were obtained by Xu et al, and extended to the case of rotation. Based on these two metrics of spherically symmetric black hole, we study the echo signals of CDM and SFDM models in scalar and electromagnetic fields, and make comparisons with the Schwarzschild black hole. Our results show that the black hole echoes in dark matter halo are different from the Schwarzschild black hole, hence the signals of echo can be used to distinguish different dark matter models. The echo signals appear after the first exponential decay, and decrease with increasing parameter $l$. The values of echo of CDM are approximately between $10^{-1}$ and $10^{-5}$, that of SFDM are between $10^{-2}$ and $10^{-6}$; The values of classic black hole are approximately between $10^{-4}$ and $10^{-8}$. The overall echoes of CDM are stronger than that of SFDM in the same condition, which is easier to be detected. In addition, the values of echo frequency using the six-order WKB method and Prony method are in good agreement.
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