Related papers: Neutron star heating vs. HST observations
We simulate cooling of superfluid neutron stars with nucleon cores where direct Urca process is forbidden. We adopt density dependent critical temperatures $T_{cp}(\rho)$ and $T_{cn}(\rho)$ of singlet-state proton and triplet-state neutron…
We find a new mechanism of neutron star radiation wherein radiation is produced by the stellar interior. The source of radiation is oscillating neutron vortices in the superfluid core of a rotating neutron star. Thermally excited helical…
Crustal cooling of accretion-heated neutron stars provides insight into the stellar interior of neutron stars. The neutron star X-ray transient, KS~1731$-$260, was in outburst for 12.5 years before returning to quiescence in 2001. We have…
Nuclear reactions occurring deep in the crust of a transiently accreting neutron star efficiently maintain the core at a temperature >5e7 K. When accretion halts, the envelope relaxes to a thermal equilibrium set by the flux from the hot…
Differential rotation between the neutron star crust and a more rapidly rotating interior superfluid leads to frictional heating that affects the star's long-term thermal evolution and resulting surface emission. Here we present the results…
Within the "nuclear medium cooling" scenario of neutron stars all reliably known temperature - age data, including those of the central compact objects in the supernova remnants of Cassiopeia A and XMMU-J1732, can be comfortably explained…
Recent observations of the late ($t=10^8$--$10^9$ s) emission of supernovae (SNe) associated to GRBs (GRB-SN) show a distinctive emission in the X-ray regime consistent with temperatures $10^7$--$10^8$ K. Similar features have been also…
It is now possible to model thermal relaxation of neutron stars after bouts of accretion during which the star is heated out of equilibrium by nuclear reactions in its crust. Major uncertainties in these models can be encapsulated in modest…
The impact of various competing heating processes on the thermal evolution of neutron stars is investigated. We show that internal heating leads to significantly enhanced surface temperatures for pulsars of middle and old age. The heating…
The general statement that hypothetical strange (quark matter) 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…
Neutron star models with maximum mass close to $2 \ M_{\odot}$ reach high central densities, which may activate nucleonic and hyperon direct Urca neutrino emission. To alleviate the tension between fast theoretical cooling rates and thermal…
We study thermal states of transiently accreting neutron stars (with mean accretion rates $\dot{M} \sim 10^{-14}-10^{-9}$ M$_\odot$ yr$^{-1}$) determined by the deep crustal heating of accreted matter sinking into stellar interiors. We…
We calculate the thermal structure and quiescent thermal luminosity of accreting neutron stars (warmed by deep crustal heating in accreted matter) in soft X-ray transients (SXTs). We consider neutron stars with nucleon and hyperon cores and…
We present a multi-epoch spectral and timing analysis of the isolated neutron star RBS1223. New XMM-Newton data obtained in January 2004 confirm the spin period to be twice as long as previously thought, P_spin = 10.31 s. The combined…
The heating and cooling of transiently accreting neutron stars provides a powerful probe of the structure and composition of their crust. Observations of superbursts and crust cooling of accretion-heated neutron stars require more heat…
Recent analyses on the central compact object in the HESS J1731-347 supernova remnant reported not only surprising structural properties (mass $M$ and radius $R$), but also an interesting thermal evolution. More precisely, it has been…
We present 3D Newtonian simulations of the coalescence of two neutron stars, using a Smoothed Particle Hydrodynamics (SPH) code. We begin the simulations with the two stars in a hard, circular binary, and have them spiral together as…
When a rotating neutron star loses angular momentum, the reduction of the centrifugal force makes it contract. This perturbs each fluid element, raising the local pressure and originating deviations from beta equilibrium, inducing reactions…
The temperature of a newly formed neutron star is believed to be as high as $10^{11}$~K, corresponding to a thermal energy of about $10$ MeV. After a time $t \sim 50 \ {\rm s}$, the neutrino mean free path in nuclear matter exceeds the…
When neutron stars reside in transient X-ray binaries, their crustal layers become heated during accretion outbursts and subsequently cool in quiescence. Observing and modeling this thermal response has yielded valuable insight into the…