CaWO4 crystals as scintillators for cryogenic dark matter search
CaWO4 crystals as scintillators for cryogenic dark matter search
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CaWO4 晶体作为闪烁体用于低温暗物质搜索
DOI：
10.1016/j.nima.2004.08.039
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发表时间：
2005
影响因子：
1.4
通讯作者：
S. Uchaikin
中科院分区：
文献类型：
--
作者：
J. Ninković;G. Angloher;C. Bucci;C. Cozzini;T. Frank;D. Hauff;H. Kraus;B. Majorovits;V. Mikhailik;F. Petricca;F. Pröbst;Y. Ramachers;W. Rau;W. Seidel;S. Uchaikin
虽然众所周知，CaWO4是一种闪烁体，但它并不经常使用，主要是因为它的光响应速度很慢。然而，高Z值和良好的光输出使这种晶体成为直接暗物质搜索实验的候选材料。使用超导温度计的低温稀有事件搜索(CRESST II)实验寻找假想的被称为弱相互作用大质量粒子(WIMP)的大质量基本粒子。在WIMP与普通物质的弹性碰撞中，WIMP将其部分能量传递给原子核。这种核反冲正是暗物质搜索所寻找的信号。CRESST正在使用CaWO4晶体，对声子和闪烁光进行一致检测，以抑制放射性本底。系统地测量了不同CaWO4样品的光输出和能量分辨率。最佳样品的能量分辨率为137Cs线(661keV)<；8%。由于CRESST是一个罕见的事件搜索实验，它必须防止自然放射性引起的本底；因此，我们对CaWO_4晶体的放射性纯度进行了研究。将介绍晶体样品在77-500K温度范围内的X射线发光特性。
Although it is well known that CaWO4is a scintillator it is not often used, mainly because it has a slow light response. However, a high Z and a good light output make this crystal a candidate for use in direct dark matter search experiments. The Cryogenic Rare Event Search using Superconducting Thermometers (CRESST II) experiment looks for hypothetical massive elementary particles called Weakly Interacting Massive Particles (WIMPs). In an elastic collision of WIMPs with ordinary matter a WIMP transfers part of its energy to a nucleus. Such nuclear recoils are the signals dark matter searches look for. CRESST is using CaWO4crystals with coincident detection of phonons and scintillation light to suppress radioactive background. Light output and energy resolution of different CaWO4samples were systematically measured. Best samples have an energy resolution at the137Cs line (661keV)<8%. As CRESST is a rare event search experiment it has to prevent the background caused by natural radioactivity; therefore, a study of the radiopurity of CaWO4crystals has been performed. X-ray luminescence properties of crystal samples, in the temperature range 77–500K, will be presented.