The Development of the Polarized Target of COMPASS Spectrometer for the Measurement of Drell-Yan Reaction

为了揭示夸克-胶子角动量对核子自旋的影响，我们在欧洲核子研究中心进行了Drell-Yan实验的初步实验。初步实验包括两个部分。一是检查光束引起的热对目标偏振的降低。另一种方法是利用介子光束检测背景事件。两种测试都保证了Drell-Yan实验在不降低目标偏振和使用较短的目标和强子吸收体长度的较少背景的情况下进行。我们制作了将用于Drell-Yan实验的靶架。考虑到这些初步结果，CERN决定在2013-2015年期间将测量时间分享给COMPASS进行Drell-Yan实验。

We performed the preliminary experiments at CERN for the Drell-Yan experiment to reveal the contribution of the quark-gluon angular momentum to the nucleon spin. The preliminary experiments consist of two parts. One is to check the decrease of the target polarization by heat caused by beam. Another is to check the background events using pion beam. Both tests assured the Drell-Yan experiment without decreasing the target polarization and with less background using the shorter length of the target and hadron absorber. We made the target holder which will be used for the Drell-Yan experiment. Looking those preliminary results, CERN decided to share the measuring time to COMPASS for Drell-Yan experiment during2013-2015.