A search for particle dark matter using cryogenic germanium and silicon detectors in the one- and two- tower runs of CDMS-II at Soudan
A search for particle dark matter using cryogenic germanium and silicon detectors in the one- and two- tower runs of CDMS-II at Soudan
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在苏丹 CDMS-II 的一塔和两塔运行中使用低温锗和硅探测器搜索粒子暗物质
DOI：
10.2172/935475
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发表时间：
2008
影响因子：
3.5
通讯作者：
Iv Reuben Walter Ogburn
中科院分区：
文献类型：
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作者：
Iv Reuben Walter Ogburn
子弹星系团在可见光、X射线和引力透镜下的图像证实，宇宙中的大部分物质不是由任何已知形式的物质组成的。来自星系和星系团的动力学、宇宙微波背景辐射、大爆炸核合成和其他观测的综合证据表明，宇宙中80%的物质是黑暗的，几乎没有碰撞，而且很冷。虽然我们还不知道暗物质的身份，但是大质量弱相互作用粒子（WIMPs）是一个很好的候选者。它们是标准模型的许多超对称扩展的自然组成部分，并且可以作为早期宇宙中的非相对论性热遗迹产生，其密度大约可以解释丢失的质量。星系的暗物质应该以球形或椭圆形的云存在，称为“晕”，因为它延伸到可见星系的边缘。低温暗物质搜索（CDMS）试图使用锗和硅晶体直接探测银河系暗物质晕中WIMP之间的相互作用。我们的Z敏感电离和声子（'ZIP'）探测器同时测量粒子相互作用产生的声子和电离。为了发现更多非常罕见的低能WIMP相互作用，他们必须识别和拒绝由环境放射性、探测器上的放射性污染物和宇宙射线引起的背景事件。特别是，需要对声子信号的时序进行复杂的分析，以消除由探测器表面的β衰变引起的信号。本文介绍了明尼苏达州苏丹地下实验室深地下实验场的前两个暗物质数据集。这些被称为“运行118”，有六个探测器（1公斤锗，切割前65.2天）和“运行119”，有十二个探测器（1.5公斤锗，切割前74.5天）。他们在一个单一的组合分析中分析了两次运行的所有数据，对低能相互作用具有敏感性，仔细控制数据质量和稳定性，并进一步开发了重建事件位置和拒绝β衰变近表面相互作用的技术。他们还提出了一个修订，以前发表的运行119分析，一个低阈值（1或2千电子伏）分析的Soudan数据的可行性论证，并审查有关的电离信号的电荷产生和猝灭的文献。«少
Images of the Bullet Cluster of galaxies in visible light, X-rays, and through gravitational lensing confirm that most of the matter in the universe is not composed of any known form of matter. The combined evidence from the dynamics of galaxies and clusters of galaxies, the cosmic microwave background, big bang nucleosynthesis, and other observations indicates that 80% of the universe's matter is dark, nearly collisionless, and cold. The identify of the dar, matter remains unknown, but weakly interacting massive particles (WIMPs) are a very good candidate. They are a natural part of many supersymmetric extensions to the standard model, and could be produced as a nonrelativistic, thermal relic in the early universe with about the right density to account for the missing mass. The dark matter of a galaxy should exist as a spherical or ellipsoidal cloud, called a 'halo' because it extends well past the edge of the visible galaxy. The Cryogenic Dark Matter Search (CDMS) seeks to directly detect interactions between WIMPs in the Milky Way's galactic dark matter halo using crystals of germanium and silicon. Our Z-sensitive ionization and phonon ('ZIP') detectors simultaneously measure both phonons and ionization produced by particle interactions. In order to findmore » very rare, low-energy WIMP interactions, they must identify and reject background events caused by environmental radioactivity, radioactive contaminants on the detector,s and cosmic rays. In particular, sophisticated analysis of the timing of phonon signals is needed to eliminate signals caused by beta decays at the detector surfaces. This thesis presents the firs two dark matter data sets from the deep underground experimental site at the Soudan Underground Laboratory in Minnesota. These are known as 'Run 118', with six detectors (1 kg Ge, 65.2 live days before cuts) and 'Run 119', with twelve detectors (1.5 kg Ge, 74.5 live days before cuts). They have analyzed all data from the two runs together in a single, combined analysis, with sensitivity to lower-energy interactions, careful control of data quality and stability, and further development of techniques for reconstructing event location and rejecting near-surface interactions from beta decays. They also present a revision to the previously published Run 119 analysis, a demonstration of the feasibility of a low-threshold (1 or 2 keV) analysis of Soudan data, and a review of the literature on charge generation and quenching relevant to the ionization signal.« less