Testing internal dynamics in neutron stars with radio pulsar timing

Reginald Christian Bernardo

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arXiv · 2610.02291

Testing internal dynamics in neutron stars with radio pulsar timing

Reginald Christian Bernardo

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Abstract

Rotational variations in pulsars reflect either internal angular momentum exchange via equal and opposite torques (stationary spin noise) or independent torques causing diffusive changes in total angular momentum (nonstationary spin noise). We compare two models of a radio-emitting crust and interior superfluid to test the stationarity of angular velocity fluctuations through observed pulsar phases. We present results for three isolated pulsars with measurable timing noise, demonstrating distinct inference outcomes. For PSR J1359-6038, the data mildly favor independent torques over equal-and-opposite torques, with an odds ratio of seven hundred to one. For PSR B1937+21, the analysis shows no clear preference between the models. For Vela in a pre-glitch interval, excess scatter and unexplained residual structure limit the interpretation.

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Reginald Christian Bernardo. 2026-10-01. Testing internal dynamics in neutron stars with radio pulsar timing. https://arxiv.org/abs/2610.02291

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