Jing Wang, Cheng-min Zhang
Based on the accretion-induced field decay and spin-up model, we perform
Monte Carlo test for the distribution and evolution of magnetic field and spin
period for the recycled pulsars in accreting systems. Taking wide ranges of
initial conditions, i.e. initial magnetic field $B_0 = 10^{10.5-14}$ G, initial
spin period $P_0 = 0.5-100$ s, accretion rate $\dot{M} = 10^{16-18}$ g/s,
evolution time $t = 10^{7-9}$ yr, neutron star (NS) mass $M = 0.9-2.2
M_{\odot}$ and NS radius $R = 10-20$ km into consideration, we test the initial
distribution (including initially normal and Gaussian distributions) and the
evolution of magnetic field and spin period for the recycled pulsars. We find
that initially Gaussian distribution matches the observations very well. The
minimums of magnetic field ($B \sim 10^{8-9} G$) and spin period ($P \sim 1-20
ms$) are independent of the initial distributions. Magnetic field and spin
period decrease with the increasing accretion mass, and both of them reach the
minimums when accreting about $0.1 - 0.2 M_{\odot}$.
View original:
http://arxiv.org/abs/1101.3042
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