Liquid Xe Homogeneous Shower Calorimeter with Excellent Energy Resolution in the GeV Region

液态 Xe 均质簇射热量计，在 GeV 区域具有出色的能量分辨率

• 批准号: 03554005
• 负责人: DOKE Tadayoshi
• 金额: $ 8.32万
• 依托单位: Waseda University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Developmental Scientific Research (B)
• 财政年份: 1991
• 资助国家: 日本
• 起止时间: 1991 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-03554005/
• 关键词: Liquid Xe; Homogeneous ionization calorimeter; GeV region; High energy resolution; Electro-magnetic shower; 均一型カロリメータ; 液体Xeカロリメータ; エネルギー分解能; シミュレィション; 同位元素弁別; カロリメーター; 液体アルゴン; 液体キセノン; GeV領域ガンマ線; 高エネルギ-分解能; 電磁カロリメ-タ-

Since 1970's, liquid Ar has been used as detection medium for electro-magnetic shower calorimeter but it has been used only as sampling calorimeter with thick converter electrodes like iron or lead to make its size compact. Therefore, the energy resolution could not achieve an excellent energy resolution as expected in the recent elementary particle experiments. If the calorimeter is used as homogeneous calorimeter in which the electrode system consists of very thin electrodes, it is expected that an excellent energy resolution of the order of 0.1% for high energy electrons can easily be realized. From such a view-point, in the middle of 1990's, liquid Kr homogeneous calorimeters have constructed in CERN and Novosibirsk for elementary particle experiments. To make calorimeter more compact, the use of liquid Xe in place of liquid Kr was hoped. Several researchers constructed prototype liquid Xe calorimeters and tested them. However, they could not achieve excellent energy resolution bec … More ause of miss design of the calorimeter or use of non-pure liquid Xe. We constructed a new liquid Xe homogenous calorimeter in 1992 and at first tested using liquid Ar in place of liquid Xe. We needed three years for getting a large amount of Xe gas. As a result, we could make the first test of our liquid Xe calorimeter at CERN in 1995. Unfortunately, in the test, we could not observe any ionization signals from the calorimeter. After some improvement of the electrode system in the calorimeter, the second test was made at CERN in 1996. The second test was successfully achieved except that the signals from the fifth readout could not be observed because the lead wire from the electrode was shorted to the ground. The results of the test for 70 GeV electrons are given as follows.The energy resolution (experiment) 2.06%The energy resolution (experiment) after correction for the 5^<th> reabout 0.96%The energy resolution (experiment) after subtraction of electron beam 0.71%momentum spread (0.65%)The energy resolution (Monte Carlo sumulation) 0.32%not including the electron beam momentum spread (0.65%)As seen from this table, the correction was made by using the energy loss in the 5^<th> reabout which was obtained by fitting to the build up curve for each event was not successful. By applying the same correction method to the result obtained by the MonteCarlo sumulation, we found that there is a good reverse correlation between the energy loss in the 5^<th> readout and the total energy loss other than the contribution from the 5th readout and the fluctuation in the correlation is much better than that for the contribution from the 5^<th> readout obtained after the correction. This shows that the correction obtained from the fitting to the observed build up curve for each event should be more modified according to the reverse correlation. At present, we are investigating about how to modify our correction under the above fact. Less

70年代以来，液态氩被用作电磁簇射量热计的检测介质，但一直只用作取样量热计，为了使体积紧凑，采用了铁或铅等厚转换电极。因此，能量分辨率不能达到在最近的基本粒子实验中期望的优异的能量分辨率。如果量热计被用作均匀量热计，其中电极系统由非常薄的电极组成，预计可以容易地实现对于高能电子的0.1%量级的优异能量分辨率。从这一观点出发，90年代中期，欧洲核子研究中心和新西伯利亚相继建成了用于基本粒子实验的液体氪均匀量热计。为了使量热计更紧凑，人们希望用液体氪代替液体氪。几位研究人员建造了液体热量计的原型并进行了测试。然而，它们不能实现优异的能量分辨率， ...更多信息 由于量热计的设计失误或使用非纯液体介质，我们在1992年建造了一个新的液体均质量热计，并首次用液体Ar代替液体Ar进行了测试。我们用了三年时间才弄到大量的沼气。因此，我们可以在1995年在欧洲核子研究中心对我们的液体热量计进行第一次测试。不幸的是，在测试中，我们无法观察到来自量热计的任何电离信号。在对量热计的电极系统进行了一些改进之后，1996年在CERN进行了第二次测试。成功完成了第二次测试，但由于电极的导线与接地短路，无法观察到第五次读数的信号。对70 GeV电子的测试结果如下：能量分辨率（实验）为2.06%，对5GeV电子校正后的能量分辨率（实验）约为0.96%，能量分辨率（实验）约为<th>0.96（实验）减去电子束0.71%动量扩散后（0.65%）能量分辨率（Monte Carlo模拟）0.32%不包括电子束动量扩散（0.65%）从该表中可以看出，通过使用<th>通过拟合到每个事件的建立曲线而获得的5 μ m中的能量损失来进行校正是不成功的。通过对蒙特卡洛模拟结果进行同样的修正，发现除了第5次读出的贡献外，第5次读出的能量损失与总能量损失之间有很好的反相关性<th>，而且修正后的相关性起伏要比修正后的第5次读出的贡献好得多<th>。这表明，根据反向相关性，从拟合到每个事件的观察到的建立曲线获得的校正应该被更多地修改。目前，我们正在研究如何在上述事实下修改我们的更正。少

项目成果

T.Doke,K.Kasaharta,and D.Suson: "Design of a Liquid Xenon Calorimeter for the Observation of Cosmic Ray Lines in the 1〜100 GeV Region" Jpn.J.Appl.Phys.31. 3688-3694 (1992)

T.Doke、K.Kasaharta 和 D.Suson：“用于观测 1~100 GeV 区域宇宙射线线的液态氙热量计的设计”Jpn.J.Appl.Phys.31 3688-3694（1992 年） ）

K.Masuda, T.Doke, K.Kasahara, T.Kashiwagi, and H.Hirayama: "Liquid Xe ionization calorimeter with excellent energy resolution" Technical Report. No.95-17, Advanced Research Insutitute for Science and Engineering, Waseda Univ.(1995)

K.Masuda、T.Doke、K.Kasahara、T.Kashiwagi 和 H.Hirayama：“具有出色能量分辨率的液体氙电离量热仪”技术报告。

T.Doke: "A histrical View on the R&D for Liquid Rare Gas Detectors" Nucl.Instr.&Meth.

T.Doke：“R 的历史观点

道家忠義・菊池 順: "液体Xe検出器を用いた宇宙線・素粒子実験" 早稲田大学・理工学研究所50周年記念誌. 253-260 (1991)

Tadayoshi Michie 和 Jun Kikuchi：“使用液体 Xe 探测器进行宇宙射线和基本粒子实验”早稻田大学科学与工程学院 50 周年纪念杂志 253-260（1991 年）。

市毛、道家、柴村、その他: "Analysis of the data obtained for Au-ions with the energy of〜700MeV/n in an allene doped liquid Ar homogenous calorimeter" Nucl.Instr.& Meth.(発表予定).

Ichige、Michie、Shibamura 等人：“在丙二烯掺杂液体 Ar 均质量热计中对能量为 ~700MeV/n 的 Au 离子获得的数据进行分析”Nucl.Instr.& Meth。