Anomalous Energy Injection in the Gross-Pitaevskii Framework for Turbulence in Neutron Star Glitches

TL;DR

This study uses a simplified superfluid model to explore turbulence dynamics similar to neutron star glitches, revealing multiple turbulent regimes and an anomalous energy injection mechanism driven by quantum pressure.

Contribution

It introduces a minimal two-dimensional Gross-Pitaevskii model with pinning to simulate neutron star glitch-like turbulence and identifies a secondary energy injection process.

Findings

Transient Kolmogorov-like turbulence ($k^{-5/3}$) observed

Transition to Vinen-like scaling ($k^{-1}$) identified

Quantum pressure drives anomalous secondary energy injection

Abstract

Neutron star glitches -- sudden increases in rotational frequency -- are thought to result from angular momentum transfer via quantized vortices in the superfluid core. To investigate the underlying superfluid dynamics, we employ a two-dimensional rotating atomic Bose-Einstein condensate described by a damped Gross-Pitaevskii equation with an imposed pinning potential that serves as a simplified analogue of a crust. Within this minimal framework, we examine the emergence and evolution of turbulent vortex motion following impulsive perturbations reminiscent of glitch-like forcing. Our simulations reveal a transient Kolmogorov-like turbulent cascade ($k^{-5/3}$) that transitions to a Vinen-like scaling ($k^{-1}$). We identify an anomalous secondary injection mechanism driven primarily by quantum pressure, which can sustain turbulent fluctuations in such a system. By tuning the damping coefficient $\gamma$, we determine an optimal regime for energy transfer. While idealized, these findings illustrate how quantum turbulence with multiple scaling regimes can arise in pinned, rotating superfluids, and they suggest possible qualitative connections to vortex-mediated dynamics in neutron stars and other astrophysical superfluid systems.