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arXiv · 2109.08276

Magnetically supramassive neutron stars

Arthur G Suvorov·Kostas Glampedakis
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Abstract

It is commonly believed that neutron stars exceeding the maximum mass limit for stability could be formed in the aftermath of binary neutron star mergers, enjoying a short life of metastability before losing centrifugal support and collapsing to a black hole. It is suggested here that a similar scenario could take place when the remnant's excess mass is supported by an ultra-strong $(\gtrsim 10^{17}\,\mbox{G})$ magnetic field that could be generated during, and shortly after, coalescence. We show that such 'magnetically supramassive' neutron stars could stave off collapse and survive for a few years before their magnetic energy is sufficiently dissipated due to ambipolar diffusion. In addition, we speculate on multi-messenger signatures of such objects and discuss the robustness of our results against limitations placed by neutron superfluidity and magneto-thermal evolution.

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Arthur G Suvorov, Kostas Glampedakis. 2021-09-17. Magnetically supramassive neutron stars. https://doi.org/10.1103/physrevd.105.l061302

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