Pulsar skips: Understanding variations in the regular periods of rotating neutron stars

TL;DR

This paper explores the phenomenon of pulsar period variations, including skips and speed-ups, through older superfluid core theories and newer quantum mechanical explanations involving strange nuggets.

Contribution

It compares traditional superfluid core models with recent quantum mechanical theories to explain pulsar period irregularities.

Findings

Older pulsars tend to skip and speed up.

Younger X-ray pulsars also exhibit period skips.

Quantum theory involves strange nuggets impacting the pulsar.

Abstract

Pulsars are spinning neutron stars with very regular periods. These pulsars have, however, had instances where they exhibit a change in their periods. Older theories have shown that older pulsars have a tendency to skip and speed up. Newer theories have been created, due to the discovery that younger X-ray pulsars exhibit the same skips. The older theories explain that the core of the pulsar is a superfluid with a differential rotation and the core will occasionally exhibit solid properties to catch the crust of the pulsar and speed it up. The newer quantum mechanical theory states that quantum particle packets, called the strange nuggets, slam into the side of the pulsar to add angular momentum to the pulsar and then release it later.