Neutrino emission from triplet pairing of neutrons in neutron stars

Abstract

Neutrino emission due to the pair breaking and formation processes in the bulk triplet superfluid in neutron stars is investigated with taking into account of anomalous weak interactions. We consider the problem in the BCS approximation discarding Fermi-liquid effects. In this approach we derive self-consistent equations for anomalous vector and axial-vector vertices of weak interactions taking into account the $^{3}P_{2}- ^{3}F_{2}$ mixing. Further we simplify the problem and consider the pure $^{3}P_{2}$ pairing with $m_{j}=0$, as is adopted in the minimal cooling paradigm. As was expected because of current conservation we have obtained a large suppression of the neutrino emissivity in the vector channel. More exactly, the neutrino emission through the vector channel vanishes in the nonrelativistic limit $V_F=0$. The axial channel is also found to be moderately suppressed. The total neutrino emissivity is suppressed by a factor of $1.9\times10^{-1}$ relative to original estimates using bare weak vertices.Comment: 22 pages, 4 figure

Cooling of neutron stars in soft x-ray transients

“…Beyond the BCS approximation, the maximum value of the gap remains uncertain [70,71]. Also, we emphasize that anomalous axial contributions to the neutron triplet pairing that PBF neutrino emissivity being suppressed by a factor of ∼ 0.19 [72,73] have not yet been incorporated in the present paper, which should raise our predicted values of T max cnt (as well as the indicated n 3 P 2 gap magnitude) to some extent; a full exploration of this effect will be completed in a follow-up work.…”

Self-similarity relations for cooling superfluid neutron stars

“…In this model, the emission in the vector channel is fully suppressed by the collective effects, while the emission in the axial vector channel remains unchanged. According to Leinson (2010), collective effects may actually lower the neutrino emission efficiency four times more (q = 0.19 in ). The latter case corresponds to the restriction T C0 0.75 × 10 8 K. According to Fig.…”

Neutron Stars—Cooling and Transport

“…2.6.3). Later this effect has been reexamined in many papers for different types of baryon pairing -see Leinson (2009Leinson ( , 2010 for modern results and a critical analysis of previous works. The net result is that the collective effects virtually kill down the PBF emission for the singlet pairing of nucleons, but leave this mechanism viable for the triplet pairing.…”