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On the duration of the subsonic propeller state of neutron stars in wind-fed mass-exchange close binary systems

Nazar R. Ikhsanov
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Abstract

The condition for the subsonic propeller - accretor state transition of neutron stars in wind-fed mass-exchange binary systems is discussed. I show that the value of the break period, at which the neutron star change its state to accretor, presented by Davies & Pringle (1981) is underestimated by a factor of 7.5. The correct value is P_{\rm br} = 450 μ_{30}^{16/21} \dot{M}_{15}^{-5/7} (M/M_{\sun})^{-4/21} s. This result forced us to reconsider some basic conclusions on the efficiency of the propeller spindown mechanism.

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Nazar R. Ikhsanov. 2001-11-27. On the duration of the subsonic propeller state of neutron stars in wind-fed mass-exchange close binary systems. https://doi.org/10.1051/0004-6361%3A20010140

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