The Study of Nuclear Physics with Intermediate Energy Probes

[00:72361 . whisnant]南卡罗莱纳中间能量小组的重点是利用非极化和极化光子束研究核子和介子的相互作用。我们的实验光子核物理项目是在位于布鲁克海文国家实验室的激光电子伽马源（LEGS）和位于托马斯杰斐逊国家加速器设施（JLab）的连续电子束加速器设施（CEBAF）的大接受度光谱仪（CLAS）进行的。提出的活动显著影响三个重叠的领域：核子的自旋结构，核子-核子相互作用的研究和介子的产生。这些研究的核心是强极化氘化氢ICE （SPHICE）目标。这种新型极化高清靶允许测量不对称性，并且首次测量极化质子、中子和氘核的绝对横截面。利用LEGS和JLab （E94-117）的SPHICE，将对质子和中子的正旋极化率和Gerasimov-Drell-Hearn求和规则积分进行直接测定。用线性和圆偏振光子在LEGS上的矢量和张量偏振氘的光分解将以前所未有的细节研究三角洲共振区域的核子-核子相互作用。我们的介子产生程序研究光子-核子和介子-核子相互作用。从LEGS数据中，我们将能够做出第一个与模型无关的点光生产多极子的确定。在JLab中，阈值区域的phi介子产生将用非极化和线极化（E98-109）光子进行。矢量介子的光产生将被用来通过观察它们的双轻子衰变来测量嵌入核物质中的矢量介子的质量（E94-002）。

0072361Whisnant 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 StronglyPolarized 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).