"Neutrino
emmission from neutron stars
A. D. Kaminker
Abstract:
Detailed theoretical consideration of the main neutrino
emission mechanisms in different layers of neutron stars (NSs) are presented. Effects of nucleon superfluidity
as well as strong magnetic fields are taken into account. Some neutrino emission mechanisms are considered for the first
time with the completeness required for applications: the electron-positron pair annihilation in strong magnetic
field, the neutrino synchrotron emission of relativistic electrons and positrons, the scattering
of electrons off fluxoids (quantized flux tubes) in superconducting NS cores, neutrino-pair bremsstrahlung
in Coulomb electron-electron collisions in NS cores. Theoretical description of others is essentially
modified and specified. These mechanisms are: neutrino-pair bremsstrahlung in collisions
of electrons in a Coulomb liquid or a crystal of atomic nuclei in a NS crust, specific neutrino
emission due to singlet-state Cooper pairing of protons and triplet-state Cooper pairing of
neutrons. Cooling of NSs is simulated using realistic models of nucleon superfluidity. The theory is compared
with observations of isolated NSs. It is shown
that the assumptions of strong proton superfluidity and weak neutron superfluidity in a NS core
allow one to interpret two sources, RX J0822-43 and PSR 1055-52, hotter for their
ages, as very slowly low-mass cooling NSs. The same assumptions are needed to interpret
the observations of other sources: 1E 1207-52, RX J0002+62, Vela, PSR 0656+14, and Geminga
(and possibly RX J1856-3754), as the medium-mass, moderately cooling NSs. The constraints on physical properties of NSs
which can be inferred from such a comparison are discussed.