Neutron Rich Matter In The Laboratory And In The Heavens

Prof. Charles Horowitz (host Alford/Dickhoff), Department of Physics, Indiana University, Bloomington
September 15, 2017 at 12:00 pm
241 Compton
Event Description 

Compress almost anything to very high densities and electrons react with protons to make neutron rich matter. This material is at the heart of many fundamental questions in nuclear physics and astrophysics. What are the high-density phases of QCD? Where did the chemical elements come from? What is the structure of many compact and energetic objects in the heavens, and what determines their electromagnetic, neutrino, and gravitational-wave radiations? We describe how the thickness of the neutron skins of the 48Ca and 208Pb nuclei are being measured with parity violating electron scattering at Jefferson Laboratory and how the skins of very neutron rich nuclei can be studied at the Facility for Rare Isotope Beams. These skins depend on the pressure of neutron rich matter and have important implications for the structure of neutron stars. X-ray observations of neutron star radii and cooling constrain the equation of state, heat capacity, and neutrino emissivity of dense neutron rich matter. We expect many thousands of neutrino events from the next galactic core collapse supernova. Spin correlations in neutron rich matter reduce neutrino opacities and this may help multidimensional supernova simulations explode. These spin correlations can be simulated in the laboratory with cold atoms.