Study of hadron structure and exotic hadron in the COMPASS experiment

本研究的目的是利用欧洲核子研究中心的COMPASS国际合作项目--超级质子同步加速器研究核子的夸克胶子结构，寻找奇异强子和反应过程。我们利用极化月球光束和极化靶收集了足够的数据，并对数据进行了分析，最后得到了高精度的氘自旋相关结构函数。本文将测得的氘核结构函数归纳为：1）横极化夸克分布，2）纵极化胶子分布，3）纵极化夸克分布。我们在国内和国际会议上介绍了结果，并在国际期刊上发表。特别是1）和2）是世界上第一个测量数据，3）提高了测量数据的精度，对核子结构研究的发展作出了重大贡献。我们关于胶子的结果表明，胶子对核子自旋的贡献很小， ...更多信息 这一结果与DESY的爱马仕合作和BNL的RHIC合作的质子靶实验结果一致。我们用横向极化的氘核得到的结果表明，柯林斯和西弗斯函数在氘核上的分布几乎为零。这一结果影响了对核子内部夸克和胶子轨道角动量的理解，因为它的小表明胶子轨道角动量对核子自旋的贡献很小或为零。我们还进行了在国际上引起关注的横极化质子实验，因为爱马仕实验进行的唯一测量显示了非零的柯林斯和Sivers分布，并且结果强烈需要证实。我们还准备了下一个强子束流实验，并构建了一个液态质子靶。我们还考虑了强子束实验的实验和理论问题，并研究了奇异介子的问题。少

This research has aimed to study the precise quark-gluon structure of nucleon and to search exotic hadrons and reaction processes by using the Super Proton Synchrotron as the COMPASS international collaboration at CERN. We collected enough data with polarized moon beam and polarized target and analyzed data Finally we have extracted spin-dependent structure functions of deuteron to highly precise extent. The measured structure functions of deuteron are summarized as 1) transversely polarized quark distribution, 2) longitudinally polarized gluon distribution, 3) longitudinally polarized quark distribution. We presented results at domestic and international meetings and published at international journals. Especially the 1) and 2) were the first data in the world and the 3) was improved precision of the measured data which contributed greatly to development of study of nucleon structure. Our result concerning gluon suggests small contribution of gluon to the nucleon spin which was not an … More ticipated before and this result is also consistent with the other experimental results with proton target such as the HERMES collaboration results at DESY and the RHIC collaboration results at BNL. Our result using transversely polarized deuteron shows almost zero distributions of Collins and Sivers functions at deuteron. This result impacts on the understanding of orbital angular momentum of quark and gluon inside nucleon because its smallness suggests a small or zero contribution of gluon orbital angular momentum to the nucleon spin. We also carried out the transversely polarized proton experiment which is attracted an attention in the world because the only measurement carried by the HERMES experiment showed non-zero Collins and Sivers distributions and the results are strongly needed to be confirmed. We also prepare a next experiment using hadron beam and construct a liquid proton target. We also considered experimental and theoretical issues for the hadron beam experiment and studied to clarify the problems of exotic meson. Less