Supermassive black hole seed formation and the impact on black hole populations across cosmic time

2019 ◽  
Vol 15 (S356) ◽  
pp. 292-292
Author(s):  
Colin DeGraf
Keyword(s):  
Black Hole ◽  
Cosmic Time ◽  
Analysis Method ◽  
Seed Formation ◽  
Formation Pathway ◽  
Supermassive Black Hole ◽  
Luminosity Functions ◽  
Initial Seed ◽  
The Impact

AbstractAlthough it is well understood that supermassive black holes are found in essentially all galaxies, the mechanisms by which they initially form remain highly uncertain, despite the importance that the formation pathway can have on AGN and quasar behaviour at all redshifts. Using a post-processing analysis method combining cosmological simulations and analytic modeling, I will discuss how varying the conditions for formation of supermassive black hole seeds leads to changes in AGN populations. Looking at formation via direct collapse or from PopIII remnants, I will discuss the impact on black hole mass and luminosity functions, scaling relations, and black hole mergers, which each have effects at both high- and low-redshifts. In addition to demonstrating the importance of initial seed formation on our understanding of long-term black hole evolution, I will also show that the signatures of seed formation suggest multiple means by which upcoming electromagnetic and GW surveys (at both high- and low-z) can provide the data required to constrain initial supermassive black hole formation.

scholarly journals Supermassive black hole seed formation at high redshifts: long-term evolution of the direct collapse

2015 ◽  
Vol 456 (1) ◽  
pp. 500-511 ◽  
Author(s):  
Isaac Shlosman ◽  
Jun-Hwan Choi ◽  
Mitchell C. Begelman ◽  
Kentaro Nagamine
Keyword(s):  
Black Hole ◽  
Long Term Evolution ◽  
Seed Formation ◽  
Supermassive Black Hole ◽  
Term Evolution

scholarly journals SUPERMASSIVE BLACK HOLE GROWTH IN STARBURST GALAXIES OVER COSMIC TIME: CONSTRAINTS FROM THE DEEPESTCHANDRAFIELDS

2011 ◽  
Vol 742 (1) ◽  
pp. 3 ◽  
Author(s):  
D. A. Rafferty ◽  
W. N. Brandt ◽  
D. M. Alexander ◽  
Y. Q. Xue ◽  
F. E. Bauer ◽  
...  
Keyword(s):  
Black Hole ◽  
Cosmic Time ◽  
Starburst Galaxies ◽  
Time Constraints ◽  
Supermassive Black Hole ◽  
Black Hole Growth ◽  
Hole Growth

scholarly journals AGN feedback in numerical simulations

2009 ◽  
Vol 5 (H15) ◽  
pp. 293-293
Author(s):  
Luca Ciotti
Keyword(s):  
Black Hole ◽  
Numerical Simulations ◽  
Stellar Population ◽  
Cosmic Time ◽  
Elliptical Galaxies ◽  
Stellar Mass ◽  
Feedback Effects ◽  
Supermassive Black Hole ◽  
Physically Based ◽  
Continuous Source

AbstractThe passively evolving stellar population in elliptical galaxies (Es) provides a continuous source of fuel for accretion on the central supermassive black hole (SMBH), which is 1) extended over the entire galaxy life (but declining with cosmic time), 2) linearly proportional to the stellar mass of the host spheroid, 3) summing up to a total gas mass that is > 100 times larger than the currently observed SMBH masses, 4) available independently of merging events. The main results of numerical simulations of Es with central SMBH, in which a physically based implementation of radiative and mechanical feedback effects is considered, are presented.

scholarly journals Cosmological simulations of massive black hole seeds: predictions for next-generation electromagnetic and gravitational wave observations

2019 ◽  
Vol 491 (4) ◽  
pp. 4973-4992
Author(s):  
C DeGraf ◽  
D Sijacki
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Cosmic Time ◽  
Host Galaxy ◽  
Electromagnetic Spectrum ◽  
Massive Black Hole ◽  
Cosmological Simulations ◽  
Seed Formation ◽  
Order Of Magnitude ◽  
Low Mass

ABSTRACT We study how statistical properties of supermassive black holes depend on the frequency and conditions for massive seed formation in cosmological simulations of structure formation. We develop a novel method to recalculate detailed growth histories and merger trees of black holes within the framework of the Illustris simulation for several seed formation models, including a physically motivated model where black hole seeds only form in progenitor galaxies that conform to the conditions for direct collapse black hole formation. While all seed models considered here are in a broad agreement with present observational constraints on black hole populations from optical, UV, and X-ray studies, we find that they lead to widely different black hole number densities and halo occupation fractions, which are currently observationally unconstrained. In terms of future electromagnetic spectrum observations, the faint-end quasar luminosity function and the low-mass-end black hole–host galaxy scaling relations are very sensitive to the specific massive seed prescription. Specifically, the direct collapse model exhibits a seeding efficiency that decreases rapidly with cosmic time and produces much fewer black holes in low-mass galaxies, in contrast to the original Illustris simulation. We further find that the total black hole merger rate varies by more than one order of magnitude for different seed models, with the redshift evolution of the chirp mass changing as well. Supermassive black hole merger detections with LISA and International Pulsar Timing Array may hence provide the most direct means of constraining massive black hole seed formation in the early Universe.

scholarly journals AGN anisotropic radiative feedback set by black hole spin

2020 ◽  
Vol 495 (2) ◽  
pp. 2515-2523 ◽  
Author(s):  
W Ishibashi
Keyword(s):  
Black Hole ◽  
Cosmic Time ◽  
Polar Regions ◽  
Central Black Hole ◽  
Inclination Angles ◽  
Feedback Set ◽  
Spatially Varying ◽  
The Impact ◽  
Maximum Spin ◽  
Gas Ratio

ABSTRACT We consider the impact of anisotropic radiation on the active galactic nucleus (AGN) radiative dusty feedback. The radiation pattern originating from the accretion disc is determined by the central black hole (BH) spin. Here we analyse how such BH spin-induced angular dependence affects the dynamics and energetics of the radiation pressure-driven outflows, as well as AGN obscuration and BH accretion. In addition, we explore the effect of a spatially varying dust-to-gas ratio on the outflow propagation. We obtain two distinct trends for high-spin and low-spin objects, providing a direct connection between anisotropic feedback and BH spin. In the case of maximum spin, powerful quasi-spherical outflows can propagate on large scales, at all inclination angles with fairly uniform energetics. In contrast, in the case of zero spin, only weaker bipolar outflows can be driven in the polar directions. As a result, high BH spins can efficiently clear out the obscuring gas from most directions, whereas low BH spins can only remove dusty gas from the polar regions, hence also determining the overall AGN obscuration geometry. Due to such anisotropic feedback, high BH spins can prevent accretion of gas from most directions (except in the equatorial plane), while low BH spins allow inflows to proceed from a wider range of directions. This may have important implications for the BH growth in the early Universe. Anisotropic radiative dusty feedback, ruled by the BH spin, may thus play a major role in shaping AGN evolution over cosmic time.

Application of the Extended Theory of Planned Behavior to Understand Holiday Purchase Intention During the COVID-19 Period

2021 ◽  
pp. 268-284
Author(s):  
Gönül Göker ◽  
Ilknur Ayar
Keyword(s):  
Statistical Analysis ◽  
Theory Of Planned Behavior ◽  
Planned Behavior ◽  
Purchase Intention ◽  
Analysis Method ◽  
Extended Theory ◽  
Statistical Analysis Method ◽  
The Impact

This study aimed to evaluate the holiday purchasing intentions of touristic consumers during the COVID-19 pandemic within the scope of the expanded TPB, which is empirically tested in very large areas in the disclosure of behaviors. In this study, in addition to TPB variables, fatigue variable was included. With the long-term nature and intensity of COVID-19, many people have naturally experienced some kind of physical or psychological fatigue. The impact of this fatigue caused by COVID-19 on the intention to buy holidays can be critical. In the first part of the study, holiday purchasing intentions, COVID-19 pandemic period, theory of planned behavior, and fatigue were explained. In the methodological part of the study, 389 people who were potential touristic consumers were surveyed. The data collected from the participants were measured by statistical analysis method, and the findings were reached.

scholarly journals The impact of reionization on the formation of supermassive black hole seeds

2014 ◽  
Vol 445 (1) ◽  
pp. 686-693 ◽  
Author(s):  
Jarrett L. Johnson ◽  
Daniel J. Whalen ◽  
Bhaskar Agarwal ◽  
Jan-Pieter Paardekooper ◽  
Sadegh Khochfar
Keyword(s):  
Black Hole ◽  
Supermassive Black Hole ◽  
The Impact

scholarly journals The Radio Scream from black holes at Cosmic Dawn: a semi-analytic model for the impact of radio-loud black holes on the 21 cm global signal

2019 ◽  
Vol 492 (4) ◽  
pp. 6086-6104 ◽  
Author(s):  
Aaron Ewall-Wice ◽  
Tzu-Ching Chang ◽  
T Joseph W Lazio
Keyword(s):  
Black Holes ◽  
Black Hole ◽  
Point Sources ◽  
Absorption Feature ◽  
Analytic Model ◽  
Supermassive Black Hole ◽  
Global Signal ◽  
Deep Point ◽  
Large Populations ◽  
The Impact

ABSTRACT We use a semi-analytic model to explore the potential impact of a brief and violent period of radio-loud accretion on to black holes (The Radio Scream) during the Cosmic Dawn on the H i hyperfine 21 cm signal. We find that radio emission from supermassive black hole seeds can impact the global 21 cm signal at the level of tens to hundreds of per cent provided that they were as radio loud as $z$ ≈ 1 black holes and obscured by gas with column depths of NH ≳ 1023 cm−2. We determine plausible sets of parameters that reproduce some of the striking features of the EDGES absorption feature including its depth, timing, and side steepness while producing radio/X-ray backgrounds and source counts that are consistent with published limits. Scenarios yielding a dramatic 21 cm signature also predict large populations of ∼$\mu$Jy point sources that will be detectable in future deep surveys from the Square Kilometer Array (SKA). Thus, 21 cm measurements, complemented by deep point-source surveys, have the potential to constrain optimistic scenarios where supermassive black hole progenitors were radio loud.

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