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arXiv · 2508.20763

Updated Astrophysical Equation-of-State Constraints on the Color-Superconducting Gap

Aleksi Kurkela·Krishna Rajagopal·Rachel Steinhorst
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Abstract

We summarize and update using new NICER measurements the results of arXiv:2401.16253, in which we used various astrophysical neutron-star observations to set an upper bound on the CFL color-superconducting gap in a range of baryon chemical potentials $\mu_B \in [2.1,3.2]$, above those reached within neutron stars. We also corroborate the ``reasonable" constraint from arXiv:2401.16253 on the maximum value of the color-superconducting gap by performing a new Bayesian analysis using a prior that extends a two-segment Gaussian process connecting the whole density range between CEFT and pQCD.

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Aleksi Kurkela, Krishna Rajagopal, Rachel Steinhorst. 2025-08-28. Updated Astrophysical Equation-of-State Constraints on the Color-Superconducting Gap. https://arxiv.org/abs/2508.20763

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