Investigation on Cosmic High-Energy Electrons Accelerated in Super Navae

我们成功研制了用气球飞行的闪烁纤维气球载电子望远镜（BETS），用于观测能量从10GeV到几个100GeV的宇宙电子。通过将观测到的能谱与扩散模型所期望的能谱进行比较，研究了高能电子起源和传播的一个新方面。betts也有能力在太空中观察几年的TeV电子，我们期待在不久的将来这样的观察。年度结果摘要如下。1993年，betts的原型机和飞行试验。我们进行了模拟，研究了一种观测高能电子性能最好的探测器设计。利用加速器对闪烁光纤的基本性能进行了测试。探测器有效面积为28cm*28cm。此外，还利用核乳剂验证了该系统的位置分辨能力、电子探测能力和电荷分辨能力。9月进行了气球飞行试验，验证了该系统的综合性能，包括电子和遥测系统。1994年：改进BETS和第二次飞行——通过测试，需要对图像增强器、遥测系统和触发逻辑进行一些改进。利用第二次飞行中观测到的事件，确定了一种利用CCD图像分析重建阵雨剖面的技术。1995年：BETS-2和第三次飞行探测器通过结合两个图像处理系统来独立地从x面和y面探测阵雨剖面得到了相当大的改进。BETS-2在超过36公里的高度飞行了7.5小时，探测到频率为1.6赫兹的阵雨。结果表明，本底质子的抑制能力优于1/2000。几乎所有超过50GeV的阵雨都是在用SciFi's观察到的误差范围内的乳剂中发现的。通过对乳剂的分析，证实了这些电子与SciFi的电子一致。1996年：在CERN-SPS进行了BETS-2的加速器试验，以确认电子的探测能力和能量分辨率，通过加速器试验校准的BETS-2观测到的事件推导出10GeV至100GeV的电子能谱。少

We have successfully developed BETS (Balloon Borne Electron Telescope with Scintillating Fibers) which was flown by balloon for the observation of cosmic electrons with energies from 10GeV to a few 100GeV.A new aspcet of the origin and propagation of high energy electrons is investigated by comparing the the observed energy spectrum with those expected by a diffusion model. BETS has also capability to observe the TeV electrons for a few years in space, and we expect such an observation in near future. Summary of yearly results is presented in the following.1993 : Prototype of BETS and the flight testWe have carried out simulations to study a detector design which has the best performance for observing the high-energy electrons. The basic performance of scintillating fibers (SciFi) was tested by using accelerator beams. The effective area of detector is 28cm*28cm. Nuclear emulsion was also used for confirming the capability of position resolution, electron detection and charge resolutio … More n. A test balloon-flight was done on September to prove the total performance including the electronics and the telemetry system.1994 : Improvement of BETS and the second flightBy the test, some improvements were required on the image intensifier, the telemetry system and the trigger logics. A technique for analysis of the CCD image to reconstruct shower profiles was confirmed by using the observed events in the second flight.1995 : BETS-2 and the third flightThe detector was considerably improved by incorporating two image-processing systems to detect shower profiles independently from x and y side. The BETS-2 which was flown for 7.5 hours at an altitude more than 36km, detected showers with the frequency of 1.6Hz. It is confirmed that the rejection power of the background protons is better than 1/2000. Almost all of showers over 50GeV were identified in emulsions at the positions within an error in which showers were observed with SciFi's. The electrons which identified with SciFi's was remarkably confirmed by analysis of emulsions.1996 : Accelerator test for the calibration of BETS-2An accelerator test of BETS-2 was carried out at CERN-SPS to confirm the detection capability of electrons and the energy resolution Energy spectrum of electrons from 10GeV to 100GeV is derived by the observed events with BETS-2 calibrated by the accelerator test. Less