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arXiv · 2503.06068

Gyromagnetic Angular Momentum Interconversion in Neutron Stars

Hiroshi Funaki·Yuta Sekino·Hiroyuki Tajima·Shota Kisaka·Nobutoshi Yasutake·Mamoru Matsuo
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Abstract

We propose a novel mechanism for angular momentum (AM) exchange between the crust and core of a neutron star (NS) via the gyromagnetic effect. Using extended hydrodynamics, we model the star by incorporating macroscopic AM and microscopic AM originating from neutron orbital and spin AM. We reveal that macroscopic dynamics in the crust can inform microscopic AM in the core leading to neutron spin polarization, and offer alternative scenario of (anti-)glitches. This work highlights the overlooked multi-scale AM interconversions in NS physics, paving the way for gyromagnetic astrophysics.

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Hiroshi Funaki, Yuta Sekino, Hiroyuki Tajima, Shota Kisaka, Nobutoshi Yasutake, Mamoru Matsuo. 2025-03-08. Gyromagnetic Angular Momentum Interconversion in Neutron Stars. https://arxiv.org/abs/2503.06068

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