8 research outputs found
Circumstantial evidence for a soft nuclear symmetry energy at supra-saturation densities
Within an isospin- and momentum-dependent hadronic transport model it is
shown that the recent FOPI data on the ratio in central heavy-ion
collisions at SIS/GSI energies (Willy Reisdorf {\it et al.}, NPA {\bf 781}, 459
(2007)) provide circumstantial evidence suggesting a rather soft nuclear
symmetry energy \esym at compared to the
Akmal-Pandharipande-Ravenhall prediction. Some astrophysical implications and
the need for further experimental confirmations are discussed.Comment: Version to appear in Phys. Rev. Let
Super-soft symmetry energy encountering non-Newtonian gravity in neutron stars
Considering the non-Newtonian gravity proposed in the grand unification
theories, we show that the stability and observed global properties of neutron
stars can not rule out the super-soft nuclear symmetry energies at
supra-saturation densities. The degree of possible violation of the
Inverse-Square-Law of gravity in neutron stars is estimated using an Equation
of State (EOS) of neutron-rich nuclear matter consistent with the available
terrestrial laboratory data.Comment: Version accepted by Physical Review Letter