Abstract
By relating scalar and vector couplings of the hyperons to the inferred empirical binding of the Λ hyperon in saturated nuclear matter, we obtain compatibility of this binding energy with neutron-star masses. Use of 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, places 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). Neutrons comprise a slight majority population ∼ neutron stars with mass ∼1.5.
- Received 1 May 1991
DOI:https://doi.org/10.1103/PhysRevLett.67.2414
©1991 American Physical Society