Related papers: Improbability of DUrca process constraints EOS
We introduce a new tool for 'unmasking' the composition of neutron star (NS) interiors which is based on the fact that the state of matter at high densities determines the statistics of both NS observables, the temperature-age (TA) data as…
We study the cooling of isolated neutron stars, employing different nuclear equations of state with or without active direct Urca process, and investigate the interplay with the nuclear pairing gaps. We find that a consistent description of…
The recent measurements of the masses of the pulsar J00737-3039B and of the companion J1756-2251 and pulsars PSR J1614-2230, PSR J0348-0432 demonstrate the existence of compact stars with masses in a broad range from 1.2 to 2 $M_\odot$. To…
The direct Urca (dUrca) process is a key mechanism driving rapid neutrino cooling in neutron stars, with its baryon density activation threshold determined by the microscopic model for nuclear matter. Understanding how nuclear interactions…
Charged current neutrino-nucleon reactions, generally called Urca processes, are crucial actors of a neutron star's thermal evolution. The so-called direct processes show a pronounced threshold under which the reaction is kinematically…
A new scheme for testing nuclear matter equations of state (EsoS) at high densities using constraints from neutron star phenomenology and a flow data analysis of heavy-ion collisions is suggested. An acceptable EoS shall not allow the…
We model the quiescent luminosity of accreting neutron stars with several equation of states (EOSs), including the effect of pion condensation and superfluidity. As a consequence of comparison with the observations, we show that the results…
We model the thermal states of both isolated neutron stars and accreting neutron stars in X-ray transients in quiescence and confront them with observations. We use an equation of state and superfluid baryon gaps, which are consistently…
Recent evidence for high masses ($\sim 2~ M_\odot$) pulsars PSR J1614-2230 and PSR J0348-0432 requires neutron star matter to have a stiff equation of state (EoS). The thermal evolution of compact stars (CS) with stiff hadronic EoS…
We study a neutron star with a quark matter core under extremely strong magnetic fields. We investigate the possibility of an Urca process as a mechanism for the cooling of such a star. We found that apart from very particular cases, the…
Cooling of neutron stars (NSs) with the cores composed of neutrons, protons, and electrons is analyzed. The main cooling regulators are discussed: opening of direct Urca process in a NS central kernel; superfluidity of nucleons in NS…
The general statement that strange stars cool more rapidly than neutron stars is investigated in greater detail. It is found that the direct Urca process could be forbidden not only in neutron stars but also in strange stars. If so, strange…
The recently discovery of a massive neutron star (PSR J1614-2230 of $1.97\pm0.04M_{\odot}$) rules out the soft equation of states (EOSs) such as those included hyperons or kaon condensates at high densities, while the nuclear theory or the…
The thermal evolution of isothermal neutron stars is studied with matter both in the hadronic phase as well as in the mixed phase of hadronic matter and strange quark matter. In our models, the dominant early-stage cooling process is…
We study the bulk viscosity in neutron star cores due to modified Urca processes involving nucleons, electrons and muons and analize its reduction by singlet-state or triplet-state superfluidity of nucleons. In combination with the results…
We study equation of state (EOS) of an accreting neutron star crust. Usually, such EOS is obtained assuming (implicitly) that the free (unbound) neutrons and nuclei in the inner crust move together. We argue, that this assumption violates…
We study the "minimal" cooling scenario of superfluid neutron stars with nucleon cores, where the direct Urca process is forbidden and the enhanced cooling is produced by the neutrino emission due to Cooper pairing of neutrons. Extending…
We demonstrate that the existing neutron-star cooling data can be appropriately described within "the nuclear medium cooling scenario" including hyperons under the assumption that different sources have different masses. We use a stiff…
Observations of isolated neutron stars place constraints on the equation of state (EOS) of cold, neutron-rich matter, while nuclear physics experiments probe the EOS of hot, symmetric matter. Many dynamical phenomena, such as core-collapse…
In this work we revisit the thermal relaxation process for neutron stars. Such process is associated with the thermal coupling between the core and the crust of neutron stars. The thermal relaxation, which takes place at around 10 -- 100…