相关论文: Massive black hole formation in Population III sta…
Population III (Pop III) stars ended the cosmic Dark Ages and began early cosmological reionization and chemical enrichment. However, in spite of their importance to the evolution of the early Universe, their properties remain uncertain…
Recent systematic searches for massive black holes (BHs) in local dwarf galaxies led to the discovery of a population of faint Active Galactic Nuclei (AGN). We investigate the agreement of the BH and AGN populations in the Illustris, TNG,…
We study Population III (Pop III) binary remnant mergers in nuclear star clusters (NSCs) with a semi-analytical approach for early structure formation. Within this framework, we keep track of the dynamics of Pop III binary (compact object)…
We study the dynamics of stellar-mass black holes (BH) in star clusters with particular attention to the formation of BH-BH binaries, which are interesting as sources of gravitational waves (GW). We examine the properties of these BH-BH…
Supermassive stars, with masses greater than a million solar masses, are possible progenitors of supermassive black holes in galactic nuclei. Because of their short nuclear burning timescales, such objects can be formed only when matter is…
The detection of the gravitational wave (GW) event GW190521 raises questions about the formation of black holes within the pair-instability mass gap (PIBHs). We propose that Population III (Pop III) star clusters significantly contribute to…
Current theoretical models predict a mass gap with a dearth of stellar black holes (BHs) between roughly $50\,M_\odot$ and $100\,M_\odot$, while, above the range accessible through massive star evolution, intermediate-mass BHs (IMBHs) still…
GW190521 is a merger of two black holes (BHs), wherein at least one BH lies within the pair-instability (PI) mass gap, and it is difficult to form because of the effects of PI supernovae (PISNe) and pulsational PI (PPI). In this study, we…
As massive black holes (MBHs) grow from lower-mass seeds, it is natural to expect that a leftover population of progenitor MBHs should also exist in the present universe. Dwarf galaxies undergo a quiet merger history, and as a result, we…
Observations from the James Webb Space Telescope (JWST) have uncovered supermassive black holes (SMBHs) with masses exceeding $10^6 \mathrm{M}_{\odot}$ at redshifts $z > 8$, posing significant challenges to existing models of early black…
We discuss the link between dark matter halos hosting the first PopIII stars formed at redshift z > 40 and the rare, massive, halos that are generally considered to host bright z~6 quasars. We show that within the typical volume occupied by…
In a star cluster with a sufficiently large escape velocity, black holes (BHs) that are produced by BH mergers can be retained, dynamically form new BH binaries, and merge again. This process can repeat several times and lead to significant…
Populations of stellar-mass black holes (BHs) in globular clusters (GCs) influence their dynamical evolution and have important implications on one of the main formation channels for gravitational wave sources. Inferring the size of these…
The vast amount of energy released by active galactic nuclei (AGN) is increasingly recognized as a key driver of evolution not only in massive galaxies and clusters, but also in low-mass dwarf galaxies. Despite this, their role in the early…
We perform a binary population synthesis calculation incorporating very massive population (Pop.) III stars up to 1500 $M_\odot$, and investigate the nature of binary black hole (BBH) mergers. Above the pair-instability mass gap, we find…
We model Pop III star formation in different FUV and X-ray backgrounds, including radiation feedback from protostars. We confirm previous results that a moderate X-ray background increases the number of Pop III systems per unit cosmological…
Recent observations with the James Webb Space Telescope (JWST) reveal young massive clusters (YMCs) as key building blocks of early galaxies. They are not only important constituents of galaxies, but also potential birthplaces of very…
Halos with masses in excess of the atomic limit are believed to be ideal environments in which to form heavy black hole seeds with masses above 10^3 Msun. In cases where the H_2 fraction is suppressed this is expected to lead to reduced…
We calculate evolution, collapse, explosion, and nucleosynthesis of Population III very-massive stars with 500$M_{\odot}$ and 1000$M_{\odot}$. Presupernova evolution is calculated in spherical symmetry. Collapse and explosion are calculated…
Massive black holes (BHs) grow by gas accretion and mergers, observable through electromagnetic (EM) and gravitational wave (GW) emission. The James Webb Space Telescope (JWST) has detected faint active galactic nuclei (AGNs), revealing an…