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arXiv · 2202.12845

Neutron stars and phase diagram in a hard-wall AdS/QCD model

Lorenzo Bartolini·Sven Bjarke Gudnason·Josef Leutgeb·Anton Rebhan
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Abstract

We study the phase diagram of (large-$N_c$) QCD using a simplistic holographic hard-wall model with a dynamical scalar field and a homogeneous Ansatz representing a smeared instanton/baryon density. The resulting phase diagram is qualitatively consistent with expectations, including a mesonic, baryonic, quarkyonic, and quark-gluon plasma phase. As in other holographic models, we also find a baryonic popcorn transition, which appears at large chemical potential as a crossover. We then evaluate the nuclear matter equation of state, which turns out to be rather stiff with a large peaked sound velocity above the conformal limit, construct corresponding neutron stars using the TOV equations, and finally use a full numerical gravity/hydrodynamics computation to extract the gravitational wave signal of neutron star mergers.

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Lorenzo Bartolini, Sven Bjarke Gudnason, Josef Leutgeb, Anton Rebhan. 2022-02-25. Neutron stars and phase diagram in a hard-wall AdS/QCD model. https://doi.org/10.1103/physrevd.105.126014

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