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arXiv · 1511.05880

Mass-radius constraints for the neutron star EoS - Bayesian analysis

A. Ayriyan·D. E. Alvarez-Castillo·D. Blaschke·H. Grigorian
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Abstract

We suggest a new Bayesian analysis (BA) using disjunct M-R constraints for extracting probability measures for cold, dense matter equations of state (EoS). One of the key issues of such an analysis is the question of a deconfinement transition in compact stars and whether it proceeds as a crossover or rather as a first order transition. We show by postulating results of not yet existing radius measurements for the known pulsars with a mass of $2M_\odot$ that a radius gap of about 3 km would clearly select an EoS with a strong first order phase transition as the most probably one. This would support the existence of a critical endpoint in the QCD phase diagram under scrutiny in present and upcoming heavy-ion collision experiments.

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A. Ayriyan, D. E. Alvarez-Castillo, D. Blaschke, H. Grigorian. 2015-11-18. Mass-radius constraints for the neutron star EoS - Bayesian analysis. https://doi.org/10.1088/1742-6596%2F668%2F1%2F012038

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