Reionization of the Universe by Early-formed Massive Black Holes

Studying invisible objects in space that are hundreds of millions of light years away may sound impossible. But, in recent years, astronomers have developed a new way to investigate a type of invisible and distant objects—super-massive black holes. Black holes are the most densely packed objects in the Universe. When stars get close to super-massive black holes they can be torn apart, which produces a relatively brief but informative flash of light. These star-destroying events can help us to discover the locations of the most massive black holes in the Universe, but only if we know how to find and interpret them. In this article, we will discuss different ways we can “see” black holes, and particularly what we do and do not yet understand about stars getting “tidally disrupted” by them. Light YearThe distance light travels in a year, which is 5,878,625,370,000 miles.

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Local heating of the universe by the Higgs field

International Journal of Modern Physics D ◽

10.1142/s0218271818410031 ◽

2018 ◽

Vol 27 (06) ◽

pp. 1841003

Author(s):

K. M. Belotsky ◽

A. V. Grobov ◽

S. G. Rubin

Keyword(s):

Black Holes ◽

Black Hole ◽

Chemical Composition ◽

Scalar Field ◽

Local Heating ◽

Dynamical Behavior ◽

Higgs Field ◽

Hole Formation ◽

Massive Black Holes ◽

The Universe

It is shown that the creation of primordial massive black holes is accompanied by a local heating of the matter. The developed mechanism is based on the interaction of the Higgs field and a scalar field responsible for black hole formation. We also consider dynamical behavior of parameters such as a scale and chemical composition of such heating regions.

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Conference Summary

Proceedings of the International Astronomical Union ◽

10.1017/s1743921318000145 ◽

2017 ◽

Vol 13 (S336) ◽

pp. 451-454

Author(s):

Philip J. Diamond

Keyword(s):

Black Holes ◽

Star Formation ◽

Interstellar Medium ◽

Massive Black Holes ◽

Conference Summary ◽

Evolved Stars ◽

The Universe

AbstractIAU Symposium 336, Astrophysical Masers: Unlocking the Mysteries of the Universe, took place between 4 - 8 September, 2017 in Cagliari, on the beautiful island of Sardinia. The Symposium, the fifth focusing on masers as a tool for astrophysics, was dedicated to our friend and colleague Malcolm Walmsley, who sadly passed away shortly before the meeting. To quote Karl Menten: “Malcolm made numerous fundamental contributions to our understanding of the physics and chemistry of star formation and the interstellar medium. He was an exceptional scientist, a highly esteemed colleague and a true gentleman”. Vale Malcolm. The topics discussed at the symposium covered a huge range, from star-formation, evolved stars, galaxies and their constituents, super-massive black-holes to cosmology.

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Formation and early evolution of massive black holes

Proceedings of the International Astronomical Union ◽

10.1017/s1743921307004723 ◽

2006 ◽

Vol 2 (S238) ◽

pp. 73-82

Author(s):

Piero Madau

Keyword(s):

Black Holes ◽

Dark Matter ◽

Ionization State ◽

First Stars ◽

Massive Black Holes ◽

X Ray ◽

Hard Radiation ◽

Low Mass ◽

The Universe

AbstractThe astrophysical processes that led to the formation of the first seed black holes and to their growth into the supermassive variety that powers bright quasars at z ∼ 6 are poorly understood. In standard ΛCDM hierarchical cosmologies, the earliest massive holes (MBHs) likely formed at redshift z ≳ 15 at the centers of low-mass (M ≳ 5 × 105 M⊙) dark matter “minihalos”, and produced hard radiation by accretion. FUV/X-ray photons from such “miniquasars” may have permeated the universe more uniformly than EUV radiation, reduced gas clumping, and changed the chemistry of primordial gas. The role of accreting seed black holes in determining the thermal and ionization state of the intergalactic medium depends on the amount of cold and dense gas that forms and gets retained in protogalaxies after the formation of the first stars. The highest resolution N-body simulation to date of Galactic substructure shows that subhalos below the atomic cooling mass were very inefficient at forming stars.

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Towards a Truly Unified Model of AGN: Aspect, Accretion and Evolution

Publications of the Astronomical Society of Australia ◽

10.1071/as97230 ◽

1997 ◽

Vol 14 (3) ◽

pp. 230-245 ◽

Cited By ~ 12

Author(s):

Michael A. Dopita

Keyword(s):

Black Holes ◽

Dominant Role ◽

Unified Model ◽

Evolutionary Status ◽

Massive Black Holes ◽

Radio Jets ◽

Line Region ◽

Nuclear Regions ◽

Diagnostic Capabilities ◽

The Universe

AbstractThe Unified Model holds that the aspect-dependent effects primarily determine the nature of the active galactic nucleus that we observe. In this paper, I argue that three parameters; aspect, accretion rate into the nuclear regions, and the evolutionary status of the central black hole hold the key to unification. The mystery of why the epoch of quasar formation occurred so early in the evolution of the Universe, why radio-loud QSOs represent only a small fraction of the general population of QSOs, and why ellipticals are invariably the hosts of radio-loud active galaxies could be explained if (a) the most rapid growth of black holes occurred in galactic merger events, and if (b) an excess in the rate of nuclear feeding was able to choke off the radio jets, producing radio quiet QSOs. In this paper, I develop the idea that rate of nuclear feeding plays a dominant role and that feeding at super-Eddington rates into the broad-line region (BLR) during merger events is the means whereby massive black holes are grown. In particular, I develop a toy model for the radio-loud, radio-quiet dichotomy based on the rate of nuclear feeding, suggest an electron scattering model for the ‘big blue bump’ and its relation to the BLR, and emphasise the important diagnostic capabilities offered by analyses of the narrow line regions based on shock excitation models.

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Co-Evolution of Supermassive Black Holes and Their Host Galaxies

Proceedings of the International Astronomical Union ◽

10.1017/s1743921310005533 ◽

2009 ◽

Vol 5 (S267) ◽

pp. 34-39

Author(s):

J. K. Kotilainen ◽

R. Decarli ◽

R. Falomo ◽

A. Treves ◽

M. Labita ◽

...

Keyword(s):

Black Holes ◽

Stellar Population ◽

High Redshift ◽

Host Galaxy ◽

Host Galaxies ◽

Massive Black Holes ◽

Galaxy Masses ◽

Age Of The Universe ◽

Black Hole Masses ◽

The Universe

AbstractWe study the evolution of the MBH/Mhost relation up to z = 3 for a sample of 96 quasars with known host galaxy luminosities. Black hole masses are estimated assuming virial equilibrium in the broad-line regions, while the host galaxy masses are inferred from their luminosities. With this data, we are able to pin down the evolution of the MBH/Mhost relation over 85% of the age of the universe. While the MBH/Lhost relation remains nearly unchanged, taking into account the aging of the stellar population, we find that the MBH/Mhost ratio (Γ) increases by a factor ~ 7 from z = 0 to z = 3. We show that the evolution of Γ is independent of radio loudness and quasar luminosity. We propose that the most massive black holes, in their quasar phase at high-redshift, become extremely rare objects in host galaxies of similar mass in the local universe.

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Observational Signatures of High-Redshift Quasars and Local Relics of Black Hole Seeds

Publications of the Astronomical Society of Australia ◽

10.1017/pasa.2016.46 ◽

2016 ◽

Vol 33 ◽

Cited By ~ 37

Author(s):

Amy E. Reines ◽

Andrea Comastri

Keyword(s):

Black Holes ◽

Black Hole ◽

Dwarf Galaxies ◽

High Redshift ◽

Observational Constraints ◽

Solar Mass ◽

Massive Black Holes ◽

Eddington Limit ◽

The Universe ◽

Review Current

AbstractObservational constraints on the birth and early evolution of massive black holes come from two extreme regimes. At high redshift, quasars signal the rapid growth of billion-solar-mass black holes and indicate that these objects began remarkably heavy and/or accreted mass at rates above the Eddington limit. At low redshift, the smallest nuclear black holes known are found in dwarf galaxies and provide the most concrete limits on the mass of black hole seeds. Here, we review current observational work in these fields that together are critical for our understanding of the origin of massive black holes in the Universe.

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Supermassive Black Holes

What Does a Black Hole Look Like? ◽

10.23943/princeton/9780691148823.003.0005 ◽

2014 ◽

Author(s):

Charles D. Bailyn

Keyword(s):

Black Holes ◽

Stellar Evolution ◽

Large Fraction ◽

Supermassive Black Holes ◽

Stellar Objects ◽

Massive Black Holes ◽

Quasi Stellar Objects ◽

Age Of The Universe ◽

Luminous Objects ◽

The Universe

This chapter focuses on supermassive black holes, which are sometimes abbreviated “SMBHs.” Stellar-mass black holes are clearly common consequences of stellar evolution, but they are not the only kinds of black holes identified by astronomers. Much more massive black holes are located in the center of many, and perhaps all, galaxies. These black holes are referred to as supermassive black holes. They are responsible for a range of phenomena originating from objects described as active galactic nuclei (AGN), which were first observed in the form of quasi-stellar objects (QSOs) or quasars. AGN are among the most luminous objects in the Universe and can be observed at great distances. The distances can be so great that the light travel time from the AGN to Earth is a large fraction of the age of the Universe. They are therefore often used to probe the evolution of the Universe.

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