Advances in our understanding of the free precession candidate PSR B1828-11

Abstract

We highlight the advances and difficulties in understanding PSR B1828-11, which undergoes long-term periodic modulations in its timing and pulse shape over several years. A model comparison of precession and magnetospheric switching models based on the long-term modulation data favours the former; we discuss the implications of this in the context of short timescale switching observed in this pulsar. Furthermore, we highlight the difficulties this pulsar poses for our understanding of pulsars due to the increasing rate of the modulation period and its behaviour during a recent glitch.