A new small glitch in Vela discovered with a hidden Markov model

Abstract

A striking feature of the Vela pulsar (PSR J0835−4510) is that it undergoes sudden increases in its spin frequency, known as glitches, with a fractional amplitude of the order of 10−6 approximately every 900 d. Glitches of smaller magnitudes are also known to occur in Vela. Their distribution in both time and amplitude is less well constrained but equally important for understanding the physical process underpinning these events. In order to better understand these small glitches in Vela, an analysis of high-cadence observations from the Mount Pleasant Observatory is presented. A hidden Markov model (HMM) is used to search for small, previously undetected glitches across 24 yr of observation..