Non-strange quark stars from NJL model with proper-time regularisation
| Autor: | Chao Shi, Hong-Shi Zong, Qing-Wu Wang |
|---|---|
| Rok vydání: | 2019 |
| Předmět: |
Physics
High Energy Astrophysical Phenomena (astro-ph.HE) Spins 010308 nuclear & particles physics FOS: Physical sciences Lambda 01 natural sciences High Energy Physics - Phenomenology Neutron star High Energy Physics - Phenomenology (hep-ph) Pulsar Quark star Regularization (physics) 0103 physical sciences Astrophysics - High Energy Astrophysical Phenomena 010306 general physics Ground state Free parameter Mathematical physics |
| Zdroj: | Physical Review |
| DOI: | 10.48550/arxiv.1908.06558 |
| Popis: | The structure of a light quark star is studied within a new two-flavor Nambu–Jona-Lasinio model. By retaining the contribution from the vector term in the Fierz-transformed Lagrangian, a two-solar-mass pure quark star is achieved. To overcome the disadvantage of three-momentum truncation in the regularization procedure, we introduce the proper-time regularization. We also employ the newly proposed definition of vacuum pressure [J. Phys. G 45, 105001 (2018)], in which the quasi-Wigner vacuum (corresponding to the quasi-Wigner solution of the gap equation) is used as the reference ground state. The free parameters include only a mixing constant α which weighs the contribution from the Fierz-transformed Lagrangian. We constrain α to be around 0.9 by the observed mass of pulsars PSR J0348+0432 and PSR J1614−2230. We find that the calculated surface energy density meets the requirement (>2.80×1014 g/cm3) [Phys. Rev. D 99, 043001 (2019)]. Besides, for a 1.4-solar-mass star, the deformability Λ is calculated, which is consistent with a recent analysis on the binary neutron star merger GW170817 with Λ in (0,630) for large component spins and 300−230+420 when restricting the magnitude of the component spins [Phys. Rev. X 9, 011001 (2019)], and satisfies the constraints 200<Λ<800 of early works. |
| Databáze: | OpenAIRE |
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