Time Reversal Invariance Test in Very Slow Neutron Reactions

在Los Alamos和KEK中，对中性共振吸收反应中的奇偶校验破坏的若干实验性测试已经被捕获的伽马射线测量和中子传输方法所带来的测量结果所导致的，使用极化的缓慢中子在低中子-低中子相互作用中的弱矩阵元素。在洛斯阿拉莫斯，确定较弱的矩阵元素已经被证明是通过对复合核的统计模型的帮助来完成的。The likelihood analysis has been done for mean zero}Gaussian randam variables for the helicity asymmetries in many p-wave resonances interfered with s-wave resonances.关于另一方，退出通道对捕获伽马射线反应的影响已对KEK进行了测量。对术语A_9·sigma_n ^^*·k_<gamma>^* 已经对p波共振产生了（E_n = 0.734 eV），<139>其中sigma_n ^* 是中子自旋方向，k_^* <gamma>是发射伽马射线的方向。这些措施是有用的 ... More 时间reversal violation.Neutrons have been polarized using the polarized proton and ^3 He filters。带有Cr^V复合体的乙基糖醇中的Protons在0.4 K和25 KG中动态极化。一种新的极化方法已经开发出来，五氯丁二醇中的Protons已经被极化是由激光刺激和动态极化的一种光刺激三聚氰胺状态的Pentacene在房间温度和液体硝基温度中的液体氮素温度。3他的气体是通过光学泵的平均值来极化的，它在LaA1O_3中发现了核，所以对于时间逆转性变化的测试来说是一个非常重要的核，它可以通过动态方法的平均值来极化。极化已经超过20%了。在甲醛晶体中低能量极化中子的分化已经被测量了，并且没有发现在能量区域高于20 eV，因此，对中子传输中5折叠相关参数的测量，因为在甲醛传输中，通过甲醛变得可使用。Less（低）

Several experimental tests of parity violation in neutron resonance absorption reactions have been carried out by means of the capture gamma-ray measurement and neutron transmission method using polarized slow neutrons at Los Alamos and KEK in order to determine the weak matrix elements in hadron-hadron interactions. At Los Alamos the determination of weak matrix element has been performed with the help of statistical model of compound nucleus. The likelihood analysis has been done for mean-zero }Gaussian randam variables for the helicity asymmetries in many p-wave resonances interfered with several neighboring s-wave resonances. On the other hand, exit channel interference effects in capture gamma-ray reactions have been measured at KEK.The measurement of the term A_9・sigma_n^^*・k_<gamma>^^* has been made on the p-wave resonance (E_n=0.734eV) of ^<139>La, where sigma_n^^* is the neutron spin direction and k_<gamma>^^* is the direction of emitted gamma-rays. These measurements are usef … More ul to find out the sensitivity of the observables of the time reversal violation.Neutrons have been polarized using the polarized proton and ^3He filters. Protons in ethylene glycol with Cr^V complexes are polarized dynamically in 0.4K and 25KG.A new method of polarization has been developed, in which protons in pentacence-doped naphthalene have been polarized by means of laser excitation and dynamical polarization of a photo-excited triplet state of pentacene in room temperature and in liquid nitrogen temperature.^3He gas has been polarized by means of the optical pumping.It has been found that La nucleus in LaA1O_3, which is a very important nucleus for the test of time reversal invariance, can be polarized by means of the dynamical method. The polarization has been more than 20%.The depolarization of low energy polarized neutrons in holmium crystal has been measured and found not to be so large in the energy region higher than 20 eV.Therefore, the measurement of a 5-fold correlation parameter in the neutron transmission through holmium became feasible. Less