Neutron star moment-of-inertia in the extended Zimanyi-Moszkowski model

We revisit the extended Zimanyi-Moszkowski (EZM) model of dense neutron star (NS) core matter. In contrast to our previous work we treat the vector potentials of baryons on an equal footing with the e¤ective masses, and solve a set of 6 equations to determine the three independent e¤ective masses and vector potentials and a set of 2 equations to determine the conditions of -equilibrated NS matter, simultaneously. According to an expectation that the precisely measurable moment-of-inertia of J0737-3039A will impose a signi…cant constraint on the nuclear equation-of-state (EOS), it is calculated using the two sets of hyperon coupling constants, EZM-SU6 and EZM-P, derived from the SU(6) symmetry and the empirical data of hypernuclei. We …nd I45 = 1:23 and 1:64 that are close to the values in the EOSs of "APR" and "MS1" calculated by Morrison et al., while their mass-radius relations are rather di¤erent from the EZM models. The uniqueness of the EZM model is also apparent in the correlation map between the maximum gravitational mass of NS and the moment-of-inertia of J0737-3039A calculated for the other 25 EOSs by Bejger et al. Consequently, the EZM model is severely tested by the moment-of-inertia. However, whether the model is ruled out or not, there still remain some possibilities and problems of improving it.