Vortex Avalanches in Neutron Stars

15 May 2025, 15:30
30m
Aula Renzo Leonardi (ECT*)

Aula Renzo Leonardi

ECT*

Strada delle Tabarelle 286, I-38123 Villazzano (Trento)

Speaker

Gary Liu (Newcastle University)

Description

Rotational glitches can result from the angular momentum exchange between the curst and neutron star interiors. We study the dynamics of about 600 quantum vortices in a spinning-down two-dimensional neutron superfluid using the Gross--Pitaevskii model. For the first time, we find convincing spatial-temporal evidence of avalanching behaviour with about 10-20 vortices in each event resulting from vortex depinning and collective motion, during glitches and their post-evolutions. In the later stage, vortices continue to depin and circulate around the vorticity void in a similar manner to that seen in previous point-vortex simulations. We also demonstrate the exponential and power-law distributions in the avalanche waiting time and size under a controllable setup. Lastly, we comment on the challenge of extrapolating these results to conditions in real neutron stars, which contain many orders of magnitude more vortices.

Author

Gary Liu (Newcastle University)

Presentation materials