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arXiv · 1011.5013

Spin Period Evolution of Recycled Pulsar in Accreting Binary

J. Wang·C. M. Zhang·Y. H. Zhao·Y. Kojima·H. X. Yin·L. M. SOng
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Abstract

We investigate the spin-period evolutions of recycled pulsars in binary accreting systems. Taking both the accretion induced field decay and spin-up into consideration, we calculate their spin-period evolutions influenced by the initial magnetic-field strengths, initial spin-periods and accretion rates, respectively. The results indicate that the minimum spin-period (or maximum spin frequency) of millisecond pulsar (MSP) is independent of the initial conditions and accretion rate when the neutron star (NS) accretes $\sim> 0.2\ms$. The accretion torque with the fastness parameter and gravitational wave (GW) radiation torque may be responsible for the formation of the minimum spin-period (maximum spin frequency). The fastest spin frequency (716 Hz) of MSP can be inferred to associate with a critical fastness parameter about $\omega_{c}=0.55$. Furthermore, the comparisons with the observational data are presented in the field-period ($B-P$) diagram.

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J. Wang, C. M. Zhang, Y. H. Zhao, Y. Kojima, H. X. Yin, L. M. SOng. 2010-11-23. Spin Period Evolution of Recycled Pulsar in Accreting Binary. https://doi.org/10.1051/0004-6361/201015190

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