A hydrodynamical trigger mechanism for pulsar glitches

TL;DR

This paper proposes a new instability related to superfluid r-modes as the trigger mechanism for pulsar glitches, aligning well with observed data and offering an alternative to existing models.

Contribution

It introduces a novel superfluid r-mode instability that can trigger pulsar glitches, providing a new theoretical explanation consistent with observations.

Findings

The superfluid r-mode instability occurs at a critical rotational lag.

The model aligns with observed pulsar glitch data.

The instability offers a plausible trigger mechanism for large glitches.

Abstract

The standard explanation for large pulsar glitches involves transfer of angular momentum from an internal superfluid component to the star's crust. This model requires an instability to trigger the sudden unpinning of the vortices by means of which the superfluid rotates. This Letter describes a new instability that may play this role. The instability, which is associated with the inertial r-modes of a superfluid neutron star, sets in once the rotational lag in the system reaches a critical level. We demonstrate that our model is in good agreement with observed glitch data, suggesting that the superfluid r-mode instability may indeed be the mechanism that triggers large pulsar glitches.