Why the braking indices of young pulsars are less than 3?

被引:36
作者
Chen, WC [1 ]
Li, XD [1 ]
机构
[1] Nanjing Univ, Dept Astron, Nanjing 210093, Peoples R China
关键词
pulsars : general; stars : magnetic fields; stars : rotation;
D O I
10.1051/0004-6361:200600019
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
In this letter we discuss two possible reasons which cause the observed braking indices n of young radio pulsars to be smaller than 3: (a) the evolving spin-down model of the magnetic field component B. increases with time; (b) the extrinsic braking torque model in which the tidal torques exerted on the pulsar by the fallback disk, and carries away the spin angular momentum from the pulsar. Based on some simple assumptions, we derive the expression of the braking indices, and calculate the spin-down evolutionary tracks of pulsars for different input parameters.
引用
收藏
页码:L1 / L4
页数:4
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