Do galactic bulge X-ray sources evolve into millisecond pulsars?

Abstract

The recently discovered1 pulsar PSR1937 + 21 in 4C21.53 is remarkable for the shortness of its period (P Combining double low line 1.5 ms) and for the length2 of its characteristic age, τP Combining double low line P/2 105 yr. The simple explanation that this is an ordinary supernova-formed pulsar but with an unusually weak magnetic field and hence weak magnetic dipole radiation (ref. 3), that is, B≊2×1010(τP/105 yr) -1/2(P/1.5 ms) G fits in with the position of the pulsar close to the galactic plane. We suggest here an alternative origin for the pulsar as being the remnant of one of the 'galactic bulge' X-ray binary stars. © 1983 Nature Publishing Group.