Study on the progenitor of binary millisecond radio pulsar PSR J1713+0747

W. C. CHEN; J. A. PANEI

ASTROPHYSICAL JOURNAL

American Astronomical Society

Lugar: Hamilton, Ontario, Canadá; Año: 2009

0004-637X

PSR J1713+0747 is a millisecond radio pulsar with a spin period of 4.57 ms, and it locates in a 67.8 days circular binary orbit with a low-mass white dwarf companion. Employing the high accurate Shapiro delay caused by general relativistic effect, Splaver et al. constrained the masses of the white dwarf and the neutron star of this binary to be 0.28 \pm 0.03M_sun and 1.3 \pm 0.2M_sun (68% confidence), respectively. Standard binary evolution theory suggested that PSR J1713+0747 evolved from a low-mass X-ray binary (LMXB). In this paper, using the binary evolution code developed by Eggleton and the white dwarf evolution code given by Althaus et al. (LPCODE), we have calculated the evolutionary sequences of some LMXBs that can result in the formation of binary millisecond radio pulsars like PSR J1713+0747. During the mass exchange, the mass transfer is nonconservative and the neutron star only accrete a small part of the transfer material due to the thermally and viscously instability of the accretion disk. Our results show that, for a duty cycle of 0.01, the progenitor of PSR J1713+0747 can be constrained to be LMXBs with a donor star of ~1.3-1.6 M_sun (Z=0.02) and an initial orbital period of ~2.40-4.15 d. If the cooling timescale of the the white dwarf is 8 Gyr, its present effective temperature can be constrained to be ~3860-4070 K, which are slightly higher than that in observations. Certainly, the formation possibility of PSR J1713+0747 by accretion-induced collapse process of an accreting white dwarf cannot also be ruled out.