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

TL;DR

This paper reviews recent progress and challenges in understanding PSR B1828-11, focusing on its long-term periodic modulations and the evidence supporting free precession as the underlying mechanism.

Contribution

It compares precession and magnetospheric switching models using long-term data, favoring precession, and discusses implications for pulsar physics and recent anomalies.

Findings

Precession model is favored over switching models based on data.

The pulsar's modulation period is increasing over time.

Recent glitch behavior complicates the understanding of its dynamics.

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.