Study of New-Modes of Nuclear Excitation by Means of High-Resolution (p,n) Measurement

电荷交换（p，n）反应已经提供了一个极好的工具，可以成为研究核激发的新模式，在哪里可以看到自旋-同位素激发，例如。最近对两种不同质子能量的影响进行了调查（p，n）反应的结果是：（p，n）在IUCF （印第安纳大学回旋加速器设施）携带的中间能量，在CYRIC （回旋加速器和放射性同位素中心，东北大学）携带的其他工作也在35兆伏特质子中携带的结果。要强大的自旋依赖力，中间（p，n）似乎是非常可靠的。低能量（p，n）反应可以通过更好的能量解决方法来研究。在这个项目中，我们已经广泛地开发了高分辨率的测量方法，这些测量方法是中子飞行时间的度量。这应该被注意到，以实现100 keV对s的最高分辨率。需要30 MeV中子，一条长飞行路径（44米）。高效率探测器系统的开发也是需要的，高分辨率（p，n）测量研究的当前利益之一是<0^+> <-!><0^->转换，其中包含了关于单点交换交互的选择性信息。We have studied <DELTA>&lt;J^pi&gt; = &lt;0^-&gt; reactions on &lt;^（13）C&gt; ， &lt;^（14）N&gt; and &lt;^（15）N&gt;。一个肩膀在角度分布的1/ &lt;2^-&gt; &lt;-!&gt; 1/ &lt;2^+&gt; and &lt;1^+&gt; &lt;-!&gt; &lt;1^-&gt; transitions。这篇文章被解释为<DELTA>J（<DELTA>L，<DELTA>S） = 0 （1，1）通道中的张量相互作用。其他主题如&lt;0^+&gt; &lt;-!&gt; &lt;1^+&gt; Gamow-Teller类型的转换已经在s-d shell nuclei上进行了广泛的研究。核激发的新模式之一，其中<DELTA>J（<DELTA>L，<DELTA>S） = 2（1，1）或1（1，1），研究的例子<E_p>是Heavier核激发= 41 MeV

Charge-exchange (p,n) reactions have been proved to be an excellent tool to study new mode s of nuclear excitation , where spin-isospin excitations are observed, for example. The (p,n) reaction has been recently investigated by means of two different proton energies; i.e. (p,n) work at intermediate energy carried out at IUCF (Indiana University Cyclotron Facility), and the other works have been carried out at CYRIC (Cyclotron and Radioisotope Center, Tohoku University) with 35 MeV protons. Due to strong spin-dependent force, the intermediate (p,n) works seem to be much reliable. However, low energy (p,n) reactions may be studied with much better energy resolution. In this project, we have extensively developed the high-resolution measurement by means of the neutron time-of-flight facilities. It should be noted that to achieve a ultimated high-resolution of 100 keV v.s. 30 MeV neutrons a long flight path (44 m) is required. Thus development of the high efficient detector system was also needed.One of the current interests studied by the high-resolution (p,n) measurement is the <0^+> <-!>> <0^-> transition, which carries selectively information on one-pion exchange interaction. We have studied <DELTA> <J^pi> = <0^-> reactions on <^(13)C> , <^(14)N> and <^(15)N> . A shoulder was systematically observed around 50゜ in the angular distributions for the 1/ <2^-> <-!>> 1/ <2^+> and <1^+> <-!>> <1^-> transitions. This shoulder was interpreted as being due to the tensor interaction in the <DELTA> J( <DELTA> L, <DELTA> S) = 0 (1,1) channel. Other topics such as the <0^+> <-!>> <1^+> Gamow-Teller type transition have been extensively studied on s-d shell nuclei. One of the new modes of nuclear excitation, an example for which is <DELTA> J( <DELTA> L, <DELTA> S) = 2(1,1) or 1(1,1), were studied at <E_p> = 41 MeV for heavier nuclei.