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arXiv · 1403.2829

Upper critical field and (non)-superconductivity of magnetars

Monika Sinha·Armen Sedrakian
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Abstract

We construct equilibrium models of compact stars using a realistic equation of state and obtain the density range occupied by the proton superconductor in strong $B$-fields. We do so by combining the density profiles of our models with microscopic calculations of proton pairing gaps and the critical unpairing field $H_{c2}$ above which the proton type-II superconductivity is destroyed. We find that magnetars with interior homogeneous field within the range $0.1 \le B_{16}\le 2$, where $B_{16} = B/10^{16}$ G, are partially superconducting, whereas those with $B_{16} > 2$ are void of superconductivity. We briefly discuss the neutrino emissivity and superfluid dynamics of magnetars in the light of their (non)-superconductivity.

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Monika Sinha, Armen Sedrakian. 2014-03-12. Upper critical field and (non)-superconductivity of magnetars. https://arxiv.org/abs/1403.2829

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