Signal of quark deconfinement in thermal evolution neutron stars with deconfinement heating

In this paper, we investigate the cooling of neutron stars with relativistic and nonrelativistic models of dense nuclear matter. We focus on the effects of uncertainties originated from the nuclear models, the composition of elements in the envelope region, and the formation of superfluidity in the core and the crust of neutron stars. Discovery of [Formula: see text] neutron stars PSR J1614−2230 and PSR J0343[Formula: see text]0432 has triggered the revival of stiff nuclear equation of state at high densities. In the meantime, observation of a neutron star in Cassiopeia A for more than 10 years has provided us with very accurate data for the thermal evolution of neutron stars. Both mass and temperature of neutron stars depend critically on the equation of state of nuclear matter, so we first search for nuclear models that satisfy the constraints from mass and temperature simultaneously within a reasonable range. With selected models, we explore the effects of element composition in the envelope region, and the existence of superfluidity in the core and the crust of neutron stars. Due to uncertainty in the composition of particles in the envelope region, we obtain a range of cooling curves that can cover substantial region of observation data.

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Mutual influence of magnetic field decay and thermal evolution of rotational neutron stars

Proceedings of the International Astronomical Union ◽

10.1017/s1743921313000045 ◽

2012 ◽

Vol 8 (S291) ◽

pp. 586-588

Author(s):

Xia Zhou ◽

Miao Kang ◽

Na Wang

Keyword(s):

Magnetic Field ◽

Neutron Stars ◽

Mutual Influence ◽

Thermal Evolution ◽

Chemical Heating ◽

Field Decay ◽

The Magnetic Field

AbstractThe effect of magnetic field decay on the chemical heating and thermal evolution of neutron stars is discussed. Our main goal is to study how chemical heating mechanisms and thermal evolution are changed by field decay and how magnetic field decay is modified by the thermal evolution. We show that the effect of chemical heating is suppressed by the star spin-down through decaying magnetic field at a later stage; magnetic field decay is delayed significantly relative to stars cooling without heating mechanisms; compared to typical chemical heating, the decay of the magnetic field can even cause the temperature to turn down at a later stage.

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Thermal Evolution of Neutron Stars: Current Status

The Lives of the Neutron Stars ◽

10.1007/978-94-011-0159-2_13 ◽

1995 ◽

pp. 133-146 ◽

Cited By ~ 1

Author(s):

S. Tsuruta

Keyword(s):

Neutron Stars ◽

Thermal Evolution ◽

Current Status

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Thermal evolution and quiescent emission of transiently accreting neutron stars

Astronomy and Astrophysics ◽

10.1051/0004-6361/201936003 ◽

2019 ◽

Vol 629 ◽

pp. A88 ◽

Cited By ~ 11

Author(s):

A. Y. Potekhin ◽

A. I. Chugunov ◽

G. Chabrier

Keyword(s):

Neutron Star ◽

Neutron Stars ◽

Nuclear Reactions ◽

Thermal Evolution ◽

Theoretical Models ◽

Equilibrium Temperature ◽

Theoretical Interpretation ◽

Quasi Equilibrium ◽

Accretion Rates

Aims. We study the long-term thermal evolution of neutron stars in soft X-ray transients (SXTs), taking the deep crustal heating into account consistently with the changes of the composition of the crust. We collect observational estimates of average accretion rates and thermal luminosities of such neutron stars and compare the theory with observations. Methods. We performed simulations of thermal evolution of accreting neutron stars, considering the gradual replacement of the original nonaccreted crust by the reprocessed accreted matter, the neutrino and photon energy losses, and the deep crustal heating due to nuclear reactions in the accreted crust. We also tested and compared results for different modern theoretical models. We updated a compilation of the observational estimates of the thermal luminosities in quiescence and average accretion rates in the SXTs and compared the observational estimates with the theoretical results. Results. The long-term thermal evolution of transiently accreting neutron stars is nonmonotonic. The quasi-equilibrium temperature in quiescence reaches a minimum and then increases toward the final steady state. The quasi-equilibrium thermal luminosity of a neutron star in an SXT can be substantially lower at the minimum than in the final state. This enlarges the range of possibilities for theoretical interpretation of observations of such neutron stars. The updates of the theory and observations leave the previous conclusions unchanged, namely that the direct Urca process operates in relatively cold neutron stars and that an accreted heat-blanketing envelope is likely present in relatively hot neutron stars in the SXTs in quiescence. The results of the comparison of theory with observations favor suppression of the triplet pairing type of nucleon superfluidity in the neutron-star matter.

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Detecting UV Radiation from Nearby Pulsars with the Hubble Space Telescope

International Astronomical Union Colloquium ◽

10.1017/s0002731600155180 ◽

1992 ◽

Vol 128 ◽

pp. 220-221

Author(s):

George G. Pavlov

Keyword(s):

Magnetic Field ◽

Neutron Star ◽

Thermal Radiation ◽

Neutron Stars ◽

Hubble Space Telescope ◽

Thermal Evolution ◽

The Sun ◽

Space Telescope ◽

Additional Constraints ◽

Relativistic Particles

AbstractEven old (106 to 107 yr) pulsars within a few hundred parsecs of the Sun should give UV and optical fluxes via thermal radiation or radiation from relativistic particles. The surface temperature of a neutron star depends on its mass, radius, magnetic field, and internal composition (existence of pion condensate, superfluidity of nuclÃ©ons, etc.). If the temperature exceeds ~2x104 K, the thermal radiation can be detected by the Hubble Space Telescope. An analysis of the results will allow one to study the thermal evolution and inner structure of neutron stars in order to obtain additional constraints on pulsar models.

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