Related papers: Why NS and BH mass distribition is bimodal?
Hypermassive neutron stars (HMNSs) -- equilibrium configurations supported against collapse by rapid differential rotation -- are possible transient remnants of binary neutron star mergers. Using newly developed codes for…
The LIGO-Virgo gravitational wave detectors have confidently observed 4 events involving neutron stars: two binary neutron star (BNS) mergers (GW170817 and GW190425), and two neutron star-black hole mergers (GW200105 and GW200115). However,…
Binary stars and their interactions shape the formation of compact binaries, supernovae, and gravitational wave sources. The efficiency of mass transfer - the fraction of mass retained by the accretor during binary interaction - is a…
We analyze the LIGO/Virgo GWTC-2 catalog to study the primary mass distribution of the merging black holes. We perform hierarchical Bayesian analysis, and examine whether the mass distribution has a sharp cutoff for primary black hole…
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…
The properties of neutron stars are determined by the nature of the matter that they contain. These properties can be constrained by measurements of the star's size. We obtain stringent constraints on neutron-star radii by combining…
Recent observations identify a valley in the radius distribution of small exoplanets, with planets in the range $1.5-2.0\,{\rm R}_{\oplus}$ significantly less common than somewhat smaller or larger planets. This valley may suggest a bimodal…
Motivated by the recent discovery of a compact object with mass in the range $2.5{-}2.67\, \mathrm{M}_\odot$ in the binary merger GW190814, we revisit the question of the maximum mass of neutron stars (NSs). We use a Markov Chain Monte…
We propose that the bimodal nature of the kick velocity distribution of radio pulsars is connected with the dichotomy between hadronic stars ({\it i.e.} neutron stars with no quark matter content) and quark stars. Bimodality can appear due…
The existence of neutron stars with masses of $\sim 2\,M_{\odot}$ requires a stiff equation of state at high densities. On the other hand, the necessary appearance also at high densities of new degrees of freedom, such as hyperons and…
We report on optical spectroscopy of the eclipsing Halo LMXB 2S0921-630, that reveals the absorption line radial velocity curve of the K0III secondary star with a semi-amplitude K_2=92.89 +/- 3.84 km/s, a systemic velocity $\gamma$=34.9 +/-…
Rotational superradiance generates the amplification of incoming waves of sufficiently low frequency when scattered with a rotating absorbing body. This may be used to discover new \emph{bosonic} particles of mass $m_b$ if the rotating body…
We study centered and decentered nucleation of black holes in core-collapse of massive stars in binaries. By Bekenstein's gravitational-radiation recoil mechanism, a newly nucleated black hole typically leaves the central core prematurely.…
Massive stars with a core-halo structure are interesting objects for stellar physics and hydrodynamics. Using simulations for stellar evolution, radiation hydrodynamics, and radiative transfer, we study the explosion of stars with an…
Based on the consideration of potential energy of the di-black-hole as a function of mass asymmetry (transfer) collective coordinate, the possibility of matter transfer between the black holes in a binary system is investigated. The…
Horizontal branch (HB) stars in globular clusters offer us a probe of the mass loss mechanisms taking place in red giants. For M3 (NGC 5272), different shapes for the HB mass distribution have been suggested, including Gaussian and sharply…
The merger of binary neutron stars is likely to lead to differentially rotating remnants. In this paper, we survey several cold nuclear equations of state (EOSs) and numerically construct models of differentially rotating neutron stars in…
We evaluate the redshift distribution of binary black hole (BBH), black hole - neutron star binary (BHNS) and binary neutron star (BNS) mergers, exploring the main sources of uncertainty: star formation rate (SFR) density, metallicity…
The masses of stars including stellar remnants are almost exclusively known from binary systems. In this work, we study gravitational microlensing of faint background galaxies by isolated neutron stars (pulsars). We show that the resulting…
In a failed supernova, partial ejection of the progenitor's outer envelope can occur due to weakening of the core's gravity by neutrino emission in the protoneutron star phase. We consider emission when this ejecta sweeps up the…