The magnetar origin of pulsars
  This paper suggests the idea that all neutron stars experienced at birth an ultrafast decay of their magnetic fields from their initial values to their current surface values. If the electromagnetic energy radiated during this field decay is converted into kinetic and rotational energies of the neutron star then the decay time is of the order of 10^(-4) s provided that the initial magnetic fields lie in the range of 10^(15)-10^(16) G and the initial periods in the range 1-20 ms. This means that all neutron stars are born with magnetic fields typical of magnetars and periods typical of millisecond pulsars. More explicitly, energy considerations and a birth-ultrafast-magnetic-field decay imply a model that consistently relates birth properties of neutron stars such as the initial period and the initial magnetic field with current properties such as the observed period, the surface magnetic field and the transverse velocity. This model provides a solution to the long-standing problem of finding a physical explanation for the observed high velocities of neutron stars. These stars acquire their space velocities during the birth ultrafast decay of their magnetic fields. The origin of this field decay points to magnetic instabilities, which are inevitable if neutron stars are born as magnetars. 
Ricardo Heras
astro-ph.GA physics.class-ph