Accretion induced crust screening for the magnetic field decay of neutron stars
نویسنده
چکیده
We propose that accretion can induce a neutron star magnetic field decay because the ferromagnetic accreted matter screens the magnetic field of neutron star. Our model results suggest that: (i) the surface magnetic field decay is inversely correlated with the accretion mass in the X-ray binary accretion phase as∆M−0.4, (ii) the ‘Bottom Field Strength ’ of about 108 G can occur when the accreted matter has completely replaced the crust mass of neutron star, (iii) most of the original magnetic field is compressed into the beneath of the accreted matter, so the internal field strength is larger than the original field strength and (iv) the field-period relation is obtained which is consistent with the evolutionary track of the binary X-ray sources.
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