Related papers: The Black Hole Mass Gap as a New Probe of Millicha…
The occurrence of pair-instability supernovae is predicted to prevent the formation of black holes with masses $\gtrsim 50 M_\odot$. Recent gravitational-wave detections in this mass range require an explanation beyond that of standard…
We discuss the impact of a hidden sector consisting of Minicharged Particles (MCPs) and massless hidden photons on the expansion history of our Universe. We present parameter scans for the amount of extra relativistic particles (Neff) and…
The relations between masses of Super-Massive Black Holes, Mbh, in galactic nuclei, maximal rotational velocities, Vm, and indicative masses, Mi, of galaxies are studied for galaxies with the available rotation curves. Mbh correlates with…
The lack of objects between $2\,M_{\odot}$ and $5\,M_{\odot}$ in the joint mass distribution of compact objects has been termed "mass gap", and attributed mainly to the characteristics of the supernova mechanism precluding their birth.…
The highest critical mass of neutron stars (NSs) was reviewed in the context of equation of state and observationsl results/ It was predicted that the maximum NS mass (MNS) exists in the range MNS ~ 2.2-2.9 M_Sun. However, recent…
Pair-instability supernovae (PISN) will not leave compact remnants and hence yield a mass gap of the black holes. Though a transition point at $\approx 46M_\odot$, separating low- and high-spin black hole populations and interpreted as…
In this paper we consider collision of two particle near the STU black hole and calculate center of mass energy. In the case of uncharged black hole we find that the maximum energy obtained near the black hole horizon which similarly happen…
We discuss masses of stellar black holes found in binary systems and errors in their determination. The observed mass distribution has a broad shape within the range $4-16 M_\odot$ without visible concentration to some preferred value. On…
Stars are natural sources of feebly interacting particles, including putative particles with mass $m_\chi$ and electric charge $qe$. The emission of such millicharged particles (MCPs) causes an energy loss which can alter stellar evolution.…
Hubble Space Telescope (HST) images and spectra of the nucleated dwarf elliptical galaxy NGC 205 are combined with 3-integral axisymmetric dynamical models to constrain the mass (M_BH) of a putative nuclear black hole. This is only the…
A search for microscopic black holes in pp collisions at a center-of-mass energy of 7 TeV is presented. The data sample corresponds to an integrated luminosity of 4.7 inverse femtobarns recorded by the CMS experiment at the LHC in 2011.…
In this work we present a case that Microscopic Black Holes (MBH) of mass $10^{16}\ kg$ to $3 \cdot 10^{19}\ kg$ experience acceleration as they move within stellar material at low velocities. The accelerating forces are caused by the fact…
The mass distribution of binary black holes inferred from gravitational wave measurements is expected to shed light on their formation scenarios. An emerging structure in the mass distribution indicates the presence of multiple peaks around…
In this letter we focus on the peculiar case of a coalescing compact-object binary whose chirp mass is compatible both with a neutron star-neutron star and black hole-neutron star system, with the black hole in the $\sim 3-5M_\odot$ range…
We present a new constraint on the mass of the black hole in the active S0 galaxy NGC 5273. Due to the proximity of the galaxy at $16.6 \pm 2.1$ Mpc, we were able to resolve and extract the bulk motions of stars near the central black hole…
(Simplified) We present a theoretical framework which establishes how the core radius of a star cluster varies with the mass of an assumed central black hole. Our result is that the ratio of core to half-mass radius varies as the 3/4 power…
With the growing number of detections of binary black hole mergers, we are beginning to probe structure in the distribution of masses. A recent study by Schneider et al. proposes that isolated binary evolution of stripped stars naturally…
At low redshift, massive black holes are found in the centers of almost all large elliptical galaxies, and also in many lower-mass systems. Their evolution is believed to be inextricably entangled with that of their host galaxies. On the…
We make use of two empirical relations between the black hole mass and the global properties (bulge luminosity and stellar velocity dispersion) of nearby elliptical galaxies, to infer the mass of the central black hole (M_BH) in low…
Supermassive black holes are thought to be relics of quasars, and their numbers and masses are therefore related to the quasar luminosity function and its evolution with redshift. We have used the relationship between black hole mass and…