Related papers: Muons in supernovae: implications for the axion-mu…
We examine the roles the presence of hyperons in the cores of neutron stars may play in determining global properties of these stars. The study is based on estimates that hyperons appear in neutron star matter at about twice the nuclear…
Recently, Elshamounty et al. performed a reanalysis of the surface temperature of the neutron star in the supernova remnant Cassiopeia A on the basis of Chandra data measured during last decade, and added a new data point. We show that all…
The observed rapid cooling of the neutron star (NS) located at the center of the supernova remnant Cassiopeia A (Cas A) can be explained in the minimal NS cooling scenario. This consequence may be changed if there exists an extra cooling…
The role of a resonant $\nu_e$-$\nu_s$ oscillation is discussed in the event of a supernova explosion. It is concluded that a significant $\nu_e$-$\nu_s$ mixing may hinder the ability of the supernova to explode. It may also cool the…
A neutron star harbors of order $10^{56}$ electrons in its core, and almost the same number of muons, with muon decay prohibited by Pauli blocking. However, as macroscopic properties of the star such as its mass, rotational velocity, or…
We have considered the antikaon condensation in a neutron star in the presence of strong magnetic fields by using the modified quark-meson coupling (MQMC) model. The structure of the neutron star is investigated with various magnetic fields…
New limits on the axion-nucleon coupling over the axion mass region $10^{-24} \leq m_a \leq 5 \times 10^{-21}$ eV are derived by reanalyzing data from laboratory measurements on Lorentz and $CPT$ violation. These results establish the first…
Neutrino masses arising from the spontaneous violation of ungauged lepton-number are accompanied by a physical Goldstone boson, generically called Majoron. In the high-density supernova medium the effects of Majoron-emitting neutrino decays…
The current picture of the collapse and explosion of massive stars and the formation of neutron stars is reviewed. According to the favored scenario, however by no means proven and undisputed, neutrinos deposit the energy of the explosion…
Axions, if realized in nature, can be copiously produced in the early universe via thermal processes, contributing to the mass-energy density of thermal hot relics. In light of the most recent cosmological observations, we analyze two…
We considered recently as a new axion production mechanism the process $e^- \to e^- +a$ in a strong magnetic field $B$. Requiring that for a strongly magnetized neutron star the axion luminosity is smaller than the neutrino luminosity we…
A light hidden gauge boson with kinetic mixing with the usual photon is a popular setup in theories of dark matter. The supernova cooling via radiating the hidden boson is known to put an important constraint on the mixing. I consider the…
It has been suggested that a potentially large fraction of supernovae could be accompanied by relativistic outflows that stall below the stellar surface. In this letter we point out that internal shocks that are believed to accelerate…
Using recent supernova models, I revisit the Supernova 1987a constraints on scalar/pseudoscalar Axion-Like-Particles (ALPs). On the basis of the neutrino detections, the luminosity of ALPs must be $\lesssim 5\times10^{52} \,\mathrm{erg}/s$…
We show how the properties of the QCD axion change in systems at finite baryonic density, such as neutron stars. At nuclear saturation densities, where corrections can be reliably computed, we find a mild reduction of the axion mass and up…
We present simulations of the evolution of a proto-neutron star in which kaon-condensed matter might exist, including the effects of finite temperature and trapped neutrinos. The phase transition from pure nucleonic matter to the kaon…
We explore the interplay between supernovae and the ionizing radiation of their progenitors in star forming regions. The relative contributions of these stellar feedback processes are not well understood, particularly on scales greater than…
Axion-like particles can couple to Standard Model gluons, electroweak gauge bosons, and massive fermions. A future multi-TeV muon collider provides a favorable environment to probe axion-like particles through multiple production channels,…
The hot and dense core formed in the collapse of a massive star is a powerful source of hypothetical feebly-interacting particles such as sterile neutrinos, dark photons, axion-like particles (ALPs), and others. Radiative decays such as…
The existence of light QCD axions, whose mass depends on an additional free parameter, can lead to a new ground state of matter, where the sourced axion field reduces the nucleon effective mass. The presence of the axion field has…