Pulsar Braking Index and Mass Accretion

Abstract

I show that the braking index, $N$, a fundamental pulsar experimental quantity, naturally differs from the canonical value of 3 by terms which involve mass accretion. Using the measured values of $N$ for PSR1509-58 and PSR0531+21, I determine that for constant density neutron stars their present mass accretion rates are $(3.10\pm.51)\times10^{-5}$ M year$^{-1}$ and $(9.946\pm.089)\times10^{-5}$ M year$^{-1}$ respectively, where M is the mass of each pulsar. Finally, I demonstrate that mass accretion removes the outstanding problem of the origin of the big glitches of the Vela Pulsar.