4 Conclusion

The value of the break period at which the spinning down neutron star changes its state from the subsonic propeller to accretor obtained by Davies & Pringle (1981) is underestimated by a factor of 7.5. The incorporation of the re-estimated value of the break period into the spindown scenario suggested by Davies & Pringle shows that the propeller mechanism can be responsible for the origin of the long period X-ray pulsators even if the strength of the stellar wind, in which a neutron star is situated, is in excess of $10^{15}\,{\rm g\,s^{-1}}$. The analysis of the spin evolution of a neutron star situated in the strong stellar wind will be presented in a forthcoming paper.

Acknowledgements

I acknowledge the support of the Follow-up program of the Alexander von Humboldt Foundation. The work was partly supported by the Federal program "INTEGRATION'' under the grant KO232.