Evolution of magnetic field and spin period in accreting neutron stars
نویسنده
چکیده
Based on the accretion-induced magnetic field decay model, in which a frozen field and an incompressible fluid are assumed, we obtain the following results: (1) an analytic relation between the magnetic field and spin period, if the fastness parameter of the accretion disk is neglected (The evolutionary tracks of accreting neutron stars in the P-B diagram in our model are different from the equilibrium period lines when the influence of the fastness parameter is taken into account.); (2) the theoretical minimum spin period of an accreting neutron star ismax(1.1ms ( ∆M M )−1R−5/14 6 I45( M M )−1/2 , 1.1ms ( M M )−1/2 R 17/14 6 ), independent of the accretion rate (X-ray luminosity) but dependent on the total accretion mass, ∆M ; however, the minimum magnetic field depends on the accretion rate; (3) the magnetic field strength decreases faster with time than does the period.
منابع مشابه
The Evolution of Magnetic Field and Spin Period of Accreting Neutron Stars
Based on the accretion induced magnetic field decay model, in which frozen field and incompressible fluid are assumed, we obtain the following results. (1) The analytic relation between the magnetic field and spin period is obtained if the fastness parameter of accretion disk is neglected. Our model evolutionary tracks of accreting neutron stars in P-B diagram are different from the equilibrium...
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