RECONCILIATION OF NEUTRON-STAR MASSES AND BINDING OF THE LAMBDA IN HYPERNUCLEI

By relating scalar and vector couplings of the hyperons to the inferred empirical binding of the LAMBDA-hyperon in saturated nuclear matter, we obtain compatibility of this binding energy with neutron-star masses. Using the observational constraint on the lower bound on the maximum neutron-star mass and the upper bound of the couplings that are compatible with hypernuclear levels, we place bounds on the reduction in neutron-star mass that hyperons produce. For the best current estimate of nuclear-matter properties, the reduction in mass due to conversion of nucleons to hyperons is (0.71 +/- 0.15)M.. Neutrons comprise a slight majority population in neutron stars with mass approximately 1.5M..