The glitch in the period vs time graph above is an example of a phenomenon that is observed in other pulsars too. Then the star gets a little smaller and its rotation rate speeds up accordingly. Millisecond pulsars Some pulsars with periods of just a few milliseconds have been found. No, because many are found in globular clusters, which are very old. Neutron stars come from the death of big stars.
Big stars die soon after they are born.
Thus these stars must have gotten more angular momentum recently. The favored explanation is that they got the angular momentum from a companion star.