Bayesian inference of quark star equation of state using the <i>NICER</i> PSR J0030+0451 data
Ang Li, Zhiqiang Miao, Jin-Liang Jiang, S-P Tang, R-X Xu
Abstract
ABSTRACT We constrain the equation of state of quark stars within the Bayesian statistical approach using the mass and radius measurements of PSR J0030+0451 from NICER. Three types of bag models, with and without non-zero finite quark mass and/or superfluidity, are employed for quark stars made up with self-bound strange quark matter. We find the $90{{\ \rm per\ cent}}$ posterior credible boundary around the most probable values of the quark star maximum mass is $M_{\rm TOV}=2.38_{-0.23}^{+0.26}\, M_{\odot }$, within the model flexibility of the finite quark mass, the quark pairing gap, and the perturbative contribution from the one-gluon exchange. The radius of a canonical $1.4 \, M_{\odot }$ quark star is $R_{\rm 1.4}\sim 12.3\, {\rm km}$, smaller than the results based on neutron star models.