EAPSI: Studying Exotic Nuclear Matter with a Particle Tracking Detector and Radioactive Beams

Estee Justin B, Lansing MI

Investigators

Abstract

This award supports preparation and testing of a large detector for an upcoming experiment at the RIKEN Rare Isotope Beam Facility (RIBF) in Japan. This work will be performed with Dr. Hiroyoshi Sakurai, Chief Scientist of RIBF. The detector will be used to study exotic forms of matter produced by colliding radioactive beams only available at RIBF. Creating exotic nuclear matter in the laboratory has applications ranging from identifying and treating tumors, converting waste radioactive material into more manageable forms, to understanding the reason behind why matter is stable at all. There are hundreds of chemical elements that may be produced beyond that which can be found on earth. These elements are related to the naturally abundant elements in that they are heavy, or lighter, versions of the same element species. By adding or subtracting neutrons from an element, we can create exotic forms of matter which have interesting nuclear properties. One of the future goals in the nuclear science community is to understand the asymmetric contribution to the nuclear Equation of State (EoS) which relates pressure, energy, and temperature of nuclear matter. This asymmetric contribution is related to the cost, in energy, you must pay when moving from matter that has an equal number of protons and neutrons to unstable, neutron rich matter. The highest uncertainty of the functional form of the EoS is around nuclear densities twice that of normal nuclear matter. RIKEN is currently the only place to access beams with high enough incident energy to produce collisions reaching this density. This project will prepare a Time Projection Chamber (TPC) to be operational for an upcoming experiment. In this experiment we plan to measure the light charged particles produced in these exotic collisions thus extracting information about the nuclear EoS. This NSF EAPSI award is funded in collaboration with the Japan Society for the Promotion of Science.