Population synthesis of millisecond and submillisecond pulsars
  Known millisecond pulsars have periods longer than 1.558 ms. Recycled in binary systems, neutron stars can attain very short spin periods. In this paper we investigate the expected properties of the millisecond pulsar distribution by simulating synthetic populations under different assumptions for the neutron star equation of state and decay of the magnetic field. We find evidence that a tail in the distribution of millisecond pulsars may exist at periods shorter than those observed. 
A. Possenti (Univ. Bologna), M. Colpi (Univ. Milano), N. D'Amico (Oss.   Bologna), L. Burderi (Univ. Palermo)