相关论文: The Axial Anomaly and Large Pulsar Kicks
The puzzling phenomenon of pulsar kicks, i.e. the observed large escape velocities of pulsars out of supernova remnants, is examined for compact stars with a strange quark matter core. The direct Urca process in quark matter is studied in…
The observed velocities of radio pulsars, which range in the hundreds kilometers per second, and many of which exceed 1000 km/s, are not explained by the standard physics of the supernova explosion. However, if a sterile neutrino with mass…
Observations over the last decade have shown that neutron stars receive a large kick velocity (of order a hundred to a thousand km/s) at birth. The physical origin of the kicks and the related supernova asymmetry is one of the central…
The observed velocities of pulsars suggest the possibility that sterile neutrinos with mass of several keV are emitted from a cooling neutron star. The same sterile neutrinos could constitute all or part of cosmological dark matter. The…
X-ray pulsars shine thanks to the conversion of the gravitational energy of accreted material to X-ray radiation. The accretion rate is modulated by geometrical and hydrodynamical effects in the stellar wind of the pulsar companions and/or…
An explanation for the large random velocities of pulsars is presented. Like many other models, we propose that the momentum imparted to the star is given at birth. The ultimate source of energy is provided by the intense optically thick…
It has been recently suggested that magnetically affected neutrino oscillations inside a cooling protoneutron star, created in a supernova explosion, could explain the large proper motion of pulsars. We investigate whether this hypothesis…
We examine available observations on pulsars for evidence pertaining to mechanisms proposed to explain the origin of their velocities. We find that mechanisms predicting a correlation between the rotation axis and the pulsar velocity are…
The collapse of a massive star's core, followed by a neutrino-driven, asymmetric supernova explosion, can naturally lead to pulsar recoils and neutron star kicks. Here, we present a two-dimensional, radiation-hydrodynamic simulation in…
We show that a sterile neutrino with mass in the 1-20 keV range and a small mixing with the electron neutrino can simultaneously explain the origin of the pulsar motions and the dark matter in the universe. An asymmetric neutrino emission…
We study implications for the apparent alignment of the spin axes, proper-motions, and polarization vectors of the Crab and Vela pulsars. The spin axes are deduced from recent Chandra X-ray Observatory images that reveal jets and nebular…
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…
We explore a simple model for the representation of the observed distributions of the motions, and the characteristic ages of the local population of pulsars. The principal difference from earlier models is the introduction of a unique…
It has been suggested that the observed pulsar velocities are caused by an asymmetric neutrino emission from a hot neutron star during the first seconds after the supernova collapse. We calculate the magnitude of gravitational waves…
Two- and three-dimensional simulations demonstrate that hydrodynamic instabilities can lead to low-mode (l=1,2) asymmetries of the fluid flow in the neutrino-heated layer behind the supernova shock. This provides a natural explanation for…
We use a Monte Carlo binary synthesis code to model the formation and evolution of neutron star systems including high-mass X-ray binaries, low-mass X-ray binaries, double neutron star systems and radio pulsars. Our focus is on the…
When compact objects - neutron stars and black holes - are formed in a supernova explosion, they may receive a high velocity at formation, which may reach or even exceed 1000 km s-1 for neutron stars and hundreds of km s-1 for black holes.…
The microscopic quantum nature of elementary particles, chirality, leads to macroscopic phenomena like the chiral anomaly, chiral magnetic effect, and chiral plasma instability. We review recent progress of the studies of these chiral…
It is thought that isolated neutron stars receive a natal kick velocity at birth nearly aligned with their spin axis. Direct observational confirmation of this alignment is currently limited to a single source in a supernova remnant (PSR…
The last decade lead to major progress in asteroseismology and stellar physics with the advent of space missions. Thanks to the richness and precision of current oscillation spectra, sophisticated seismic probing techniques allow us now to…