Nuclear matter equation of state from a quark-model nucleon-nucleon interaction

Abstract

Starting from a realistic constituent quark model for the nucleon-nucleon interaction, we derive the equation of state (EOS) of nuclear matter within the Bethe-Brueckner-Goldstone approach up to three-hole-line level, without need to introduce three-nucleon forces. To estimate the uncertainty of the calculations both the gap and the continuous choices for the single-particle potential are considered and compared. The resultant EOS is compatible with the phenomenological analysis on the saturation point, the incompressibility, the symmetry energy at low density and its slope at saturation, together with the high-density pressure extracted from flow data on heavy ion collisions. Although the symmetry energy is appreciably larger in the gap choice in the high-density region, the maximum neutron star masses derived from the continuous-choice EOS and the gapchoice EOS are similar and close to two solar masses, which is again compatible with recent observational data. Comparison with other microscopic EOS is presented and discussed.

Many-body Forces in Magnetic Neutron Stars

“…In particular, it has been extensively discussed in the literature whether exotic degrees of freedom might populate the core of neutron stars. On the one hand, it is more energetically favorable for the system to populate new degrees of freedom, such as hyperons (Dexheimer & Schramm 2008;Ishizuka et al 2008;Bednarek et al 2012;Fukukawa et al 2015;Gomes et al 2015;Maslov et al 2015;Oertel et al 2015;Lonardoni et al 2015Lonardoni et al , 2016; Biswal et al 2016;Burgio & Zappalà 2016;Chatterjee & Vidana 2016;Mishra et al 2016;Vidaña 2016;Yamamoto et al 2016;Tolos et al 2017); Torres et al 2017), delta isobars (Fong et al 2010;Schurhoff et al 2010;Drago et al 2014;Cai et al 2015;Zhu et al 2016), and meson condensates (Ellis et al 1995;Menezes et al 2005;Takahashi 2007;Ohnishi et al 2009;Alford et al 2010;Fernandez et al 2010;Mesquita et al 2010;Mishra et al 2010;Lim et al 2014;Muto et al 2015), in order to lower its Fermi energy (starting at about two times the saturation density). On the other hand, the EoS softening due to the appearance of exotica might turn some nuclear models incompatible with observational data, in particular with the recently measured massive neutron stars.…”

Quark Models of the Nucleon–Nucleon Interaction

“…Finally, a NN interaction based on quark degrees of freedom has been applied to the description of the nuclear matter saturation point in Fukukawa et al [92]. These authors derive the equation of states (EOS) of nuclear matter in the framework of the Bethe-Brueckner-Goldstone approach using the fss2 interaction of Fujiwara et al [49].…”

Nuclear Equation of State for Compact Stars and Supernovae

“…Recently, it has been shown that the role of TBF is greatly reduced if the NN potential is based on a realistic constituent quark model [22] which can explain at the same time few-nucleon systems and nuclear matter, including the observational data on NSs and the experimental data on heavy-ion collisions (HICs) [167]. An extensive comparison among several EoSs obtained using different two-body and TBFs is illustrated afterwards.…”