Evolutionary Scheme for Low-Mass Binary with Millisecond Pulsar

Abstract

We present the results of evolutionary computational for the low‐mass binary (LMB) with 1.4 M⊙ neutron star (NS) as a compact companion and 1 M⊙ red dwarf as a donor star. At the moment of filling of the Roche lobe by the red dwarf an orbital system of a system is 9.h4. We take into account the illumination of the donor star by energetic quanta and particles from the NS. We focus on a regime of ‘‘non‐catastrophic’’ heating when at the beginning of mass‐transfer phase the pulsar’s illumination activates the mass loss by a donor star rather than vaporizes its outer layers. We also incorporate the effect of sweeping of overflowing plasma out of the system by the pulsar’s magneto‐dipole radiation. One issue is that the evolution of such a system may result in the formation of the LMB with rapidly rotating NS and 0.2 M⊙ red‐dwarf companion, and having orbital period ∼(6–7)h. Another issue we investigate is the regime of episodic mass loss (with approximately Eddington rate) by the donor star commencing at the ...