R & D of a Cosmic Ray Detector with Proton Beams by CERN-SPS

利用闪烁光纤对球载电子望远镜进行了加速器束试验。该探测器被转移到瑞士的欧洲核子研究中心，并被照射到能量从30 GeV到250 GeV的质子束中。这个能量区与我们观测到宇宙射线电子的能量区相对应。望远镜能够识别电子，并通过用闪烁的纤维对星雨的发展进行成像来测量能量。波束试验在西区SPS-T1/X5波束线进行。在不同条件下辐照了近10万个质子，并将数据记录在数字记录磁带上。实验得到了欧洲核子研究中心工作人员的大力支持。测试的目的在预定的时间内完全完成了。通过数据分析，我们确认了BETS的表现如下：。对质子的排斥可以通过对淋浴剖面的成像来实现。很明显，来自探测器侧面的质子也可以作为背景被触发，并且可以通过分析来排斥。对质子的排斥功率与模拟相一致。我们采用质子排斥功率，从1997年和1998年的气球数据明确地推导出电子能谱。利用波束试验结果，可以开发出一种提高抑制功率的新方法。

We have carried out accelerator beam tests for the balloon-borne electron telescope with scintillating fibers (BETS). The detector was transferred to CERN in Switzerland and was irradiated to the proton beams with energies from 30 GeV to 250 GeV.This energy region corresponds to the energy region in which we observed the cosmic-ray electrons. The telescope is capable to identify the electrons and measure the energies by imaging the shower developments with scintillating fibers.The beam tests were carried out at the SPS-T1/X5 beam line in the West Area. Nearly 100 thousands protonns were irradiated under various conditions and the data were recorded, on the digital recoding tapes. The experiment was performed by excellent supports by the CERN staffs. The purpose of the test was completely accomplished within the scheduled dates. By the data analysis, we have confirmed the performance of BETS as following :.The rejection of protons can be performed tby imaging the shower profile..It becomes clear that the protons coming from the side of detector can also be triggered as backgrounds and can be rejected by analysis..The rejection power against the protons is consistent with simulation.We have definetly derived an electron energy spectrum from the balloon data in 1997 and 1998 by adopting the proton rejection power. A new method for higher rejection power will be devldped using the beam test results.