The Study of Nuclear Physics with Intermediate Energy Probes

University Of South Carolina At Columbia, Columbia SC

Investigators

Abstract

0072361 Whisnant The focus of the South Carolina Intermediate Energy Group is the study of nucleon and meson interactions using unpolarized and polarized photon beams. Our experimental photonuclear physics program is conducted at the Laser Electron Gamma Source (LEGS) located at Brookhaven National Laboratory and with the Large Acceptance Spectrometer (CLAS) at the Continuous Electron Beam Accelerator Facility (CEBAF) located at the Thomas Jefferson National Accelerator Facility (JLab). The proposed activities significantly impact three overlapping areas: the spin structure of the nucleon, the study of the nucleon-nucleon interaction, and meson production. Central to these investigations is the Strongly Polarized Hydrogen deuteride ICE (SPHICE) target. This novel polarized HD target permits measurement of asymmetries and, for the first time, absolute cross sections on the polarized proton, neutron, and deuteron. With SPHICE at LEGS, and at JLab (E94-117), a direct determination of the forward spin-polarizability and the Gerasimov-Drell-Hearn sum rule integrals for both the proton and neutron will be made. The photodisintegration of vector and tensor polarized deuterium at LEGS with linearly and circularly polarized photons will examine the nucleon-nucleon interaction in the region of the delta resonance in unprecedented detail. Our meson production program investigates the photon-nucleon and meson-nucleon interactions. From LEGS data we will be able to make the first model-independent determination of the pionphotoproduction multipoles. At JLab, phi meson production in the threshold region will be performed with unpolarized and linearly polarized (E98-109) photons. The photoproduction of vector mesons will be used to measure the mass of vector mesons embedded in nuclear matter by observing their dilepton decay (E94-002).