Development of a high-resolution large-mass cryogenic particle detector

高分辨率大质量低温粒子探测器的研制

基本信息

批准号：
04554007
负责人：
MINOWA Makoto
金额：
$ 11.2万
依托单位：
University of Tokyo
依托单位国家：
日本
项目类别：
Grant-in-Aid for Developmental Scientific Research (B)
财政年份：
1992
资助国家：
日本
起止时间：
1992 至 1993
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-04554007/
关键词：
bolometer dilution refrigerator cryogenics thermistor double beta decay low background dark matter particle detector NTD

项目摘要

A dedicated dilution refrigerator has been constructed. It is capable of cooling one-kilogram of absorber material down to 10mK.It is made of specially selected raw materials to reduce natural radiation background from them. Especially, the inner and outer cylinders of the dewar vessel as well as the inner vacuum chamber of the refrigerator are all made of oxigen free copper.It is also made so that a lead radiation shield can be installed inside it. It has a specification suitable for a long time operation in an underground laboratory.A bolometric particle detector with an absorber of lithium fluoride crystal has been constructed with a newly developed germanium thermistor, which has a high sensitivity at around 20mK.It has been operated successfully in the dilution refrigerator.In order to manufacture many thermistors with nealy identical sensitivities, two methods were adopted. The one is to use germanium crystals melt-doped with antimony, and the other is so called neutron transmutation doping method. For the latter method, neutron irradiation has been done at the JRR-3 reactor of the Japan Atomic Energy Research Institute.We also developed bolometers with absorbers of molybdenum, nickel oxide, zinc oxide, zinc sulfide and cadmium telluride crystals for the neutrinoless double positronium decay experiment. It is found that the zinc sulfied and cadmium telluride are suitable for the bolometers of this purpose.

已经建造了专用的稀释冰箱。它能够将一公斤的吸收材料冷却至10MK。它是由特殊选择的原材料制成的，以减少其自然辐射背景。特别是，露水容器的内部和外部气缸以及冰箱的内部真空室都是由无氧化铜制成的。它具有适用于地下实验室长时间操作的规格。具有新开发的锗热敏电阻的液压粒子探测器，具有吸收氟化锂晶体的吸收仪，该固定仪在20mmk上具有高度的灵敏度。它在稀释冰箱中成功地运行了许多在稀释冰箱中，在稀释冰箱中成功地采用了许多与NeeAniv的方法。一种是使用用锑融化的锗晶体，另一种被称为中子trans变掺杂方法。对于后一种方法，已经在日本原子能研究所的JRR-3反应器上进行了中子辐射。我们还开发了具有钼，氧化镍，氧化锌，氧化锌，硫化锌和cadmium Telluride晶体的吸收剂，用于中性双质蛋白质的双峰型实验。发现锌硫酸盐和洁牙镉适合此目的的辐射仪。