Low Energy Nuclear Physics Using the Princeton Cyclotron And Atomic Physics Techniques

9420866 Cates这个提议描述了一个主要基于普林斯顿回旋加速器的核物理计划。 该研究有三个主要目标：（1）研究核子-核子相互作用中的宇称不守恒，（2）寻找β衰变中的时间（T）反转不变性，（3）研究对恒星结构和演化重要的反应。 第一个和第二个目标是完全基于原子物理技术，特别强调光学泵浦和自旋交换，特别是在一个新的偏振3 He光束的发展。 所提出的方法包括将极化的3 He气体馈送到回旋加速器的现有电离器中。 利用极化的~ 3 He束研究核子-核子相互作用中的宇称不守恒，他们提出利用中子拾取反应在~（21）Ne和~（19）Ne中产生极化激发态。 在这两种情况下，激发态都是宇称二重态的成员，宇称二重态包括两个自旋相同但宇称相反的紧密间隔的态。 通过研究平行或反平行于极化方向发射的伽马射线的不对称性，可以确定双重态内的宇称混合，提供关于核子之间存在的有效宇称非守恒势的信息。 研究人员还计划研究19 Ne和35 K β衰变中的T对称性，研究T反转非不变性的起源，这是迄今为止仅在K介子系统中观察到的现象。 预计D系数的最大极限将有一个数量级的改进。 最后，提出了对核天体物理学特别重要的几个反应的研究，以帮助解释观测到的丰度，从爆炸核合成和理解恒星的演化和结构。 ***

9420866 Cates This proposal describes a nuclear physics program based largely on the use of the Princeton Cyclotron. There are three major goals to the research: (1) the investigation of parity non- conservation in nucleon-nucleon interactions,(2) searches for time (T) reversal non-invariance in beta decay, and (3) studies of reactions that are important to stellar structure and evolution. The firsts and second goal are based entirely on atomic physics techniques, with particular emphasis on optical pumping and spin exchange especially in the development of a novel polarized 3He beam. The proposed approach involves feeding polarized 3He gas into the existing inonizer of the cyclotron. Using the polarized 3He beam to study parity non-conservation in nucleon-nucleon interactions, they proposed to use neutron pick- up reactions to make polarized excited states in 21Ne and 19Ne. In both cases, the excited states are members of parity doublets comprising two closely spaced states with identical spin but opposite parities. By studying the asymmetries of gamma rays that are emitted wither parallel or anti-parallel to the polarization direction, it is possible to determine the parity mixing within the doublets, providing information on the effective parity non-conserving potential that exists between nucleons. The researchers also plan studies of T symmetry in the beta decay of 19Ne and 35K, studying light on the origin of T reversal non-invariance, a phenomena which thus far has only been observed in the kaon system. An order of magnitude improvement in the presets limits on the D coefficient are anticipated. Finally studies are proposed of several reactions of particular importance to nuclear astrophysics, to help epsilon the observed abundance's that result from explosive nucleosynthesis and understanding stellar evolution and structure. ***