Construction of the Advanced Detectors for KEK B-factory.

为 KEK B 工厂建造先进探测器。

基本信息

批准号：
07044099
负责人：
MATSUDA Takeshi
金额：
$ 3.97万
依托单位：
National Laboratory of High Energy Physics (KEK), Japan
依托单位国家：
日本
项目类别：
Grant-in-Aid for international Scientific Research
财政年份：
1995
资助国家：
日本
起止时间：
1995 至 1996
项目状态：
已结题

项目摘要

National Laboratory for High Energy Physics, KEK,is building an asymmetric B-factory. The BELLE detector to study CP violation in B meson decays is under construction. It is expected that the BELLE experiment will provide a definitive test of CP violation in the B-meson system by measuring the three angles and the three sides of the CKM triangles. To realize this goal, a good measurement of B decay vertices and an excellent p/K identification up to 4 GeV/c are necessary. In this project, we studied the optimized design of a Silicon micro-Vertex Detector (SVD) at the B-factory and now build one made of Double-sided Silicon Strip Detectors (DSSD) with a Double-Metal Layr (DML) for the z-strip readout. We designed and tested successfully a large DSSD with DML of wide n-strip pitches, a new 128ch low-noise preamplifier chip (SMAASH chip) with 8 cell analog memory, a new bump-bonding assembly method of detector unit and DAQ-trigger modules. To make the SMAASH chip rediation-hard we test the Rapid Thermal Nitridation (RTN) process, a finer (0.6-0.8 micron) process with a low temperature oxidation. We also plan to try one of established radiation-hard processes DMILL process). As for the p/K separation at the BELLE experiment, we previously performed an intensive R&D study of the fast Ring Image Cherenkov (RICH) counter with a CsI hotocathode. It turned out unfortunately that the quantum efficiency of large CsI photocathodes was not high enough. In this project we made a R&D study of a hybrid phototube and, as a radiator of the Cherenkov light, we developed a new low-index, highly-transparent Silica Aerogel tile. This new aerogel is also higly hydrophobic and easy to handle. We currently prepare a test of a prototype RICH counter consists of the HPT ant the silica aerogel.

国家高能物理实验室KEK正在建立一个不对称的B基本。在B Meson衰减中研究CP违规的Belle探测器正在建设中。预计BELLE实验将通过测量CKM三角形的三个角度和三个侧面来对B-Meson系统中的CP违规进行确定的测试。为了实现这一目标，必须对B衰减顶点进行良好的测量和最多4 GEV/C的出色P/K识别。在这个项目中，我们研究了B-FARTORY在B-FARTORY的硅微vertex探测器（SVD）的优化设计，现在构建了一个由双面硅条探测器（DSSD）制成的，该硅条探测器（DSSD）用双倍的Layr（DML）进行Z-Strip读数。我们设计并成功测试了一个大型DSSD，它具有宽的N-Strip螺距DML，这是一种新的128ch低噪声前置放大器芯片（SMAASH芯片），该芯片（SMAASH芯片）带有8个模拟模拟存储器，一种新的检测器单元的颠簸组装方法和DAQ-Trigger模块。为了使SMAASH芯片重新修复，我们测试了快速的热硝化（RTN）过程，这是一种较低温度氧化的细胞（0.6-0.8微米）过程。我们还计划尝试一种既定的辐射过程DMILL工艺）。至于Belle实验中的P/K分离，我们以前对CSI热电话进行了对快速环图像Cherenkov（Rich）计数器进行深入的研发研究。不幸的是，大型CSI光疗的量子效率不够高。在这个项目中，我们对混合光电管进行了研发研究，作为Cherenkov Light的散热器，我们开发了一种新的低索引，高度透明的硅胶瓷砖。这个新的气凝胶也是疏水性的，易于处理。目前，我们准备了富含原型柜台的测试，由二氧化硅气凝胶组成。