An athermal phonon mediated dark matter detector with surface event discrimination
An athermal phonon mediated dark matter detector with surface event discrimination
复制标题
具有表面事件辨别功能的无热声子介导的暗物质探测器
DOI：
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发表时间：
2004
期刊：
影响因子：
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通讯作者：
R. M. Clarke
中科院分区：
文献类型：
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作者：
R. M. Clarke
有大量的观测证据表明，宇宙中的大多数物质都是暗的。大爆炸核合成的限制加上动力学估计的物质密度下限表明宇宙中存在大量的非重子暗物质。到目前为止，为了避免被探测到，这种新粒子必须只通过弱力和引力相互作用。非常古老的星系和星系团的存在强烈地指向一种粒子，这种粒子在早期宇宙的弱尺度解耦时间是非相对论性的。这种弱相互作用大质量粒子（WIMP）的一个很好的候选者是超对称（SUSY）理论预测的遗迹伙伴。如果我们的银河系晕是由WIMP组成的，我们希望它们是无耗散的，球形分布的随机玻尔兹曼速度。地球上的一个探测器，以太阳的轨道速度（10−3c）穿过星系，可以探测到WIMP与其一个原子核散射所产生的反冲能量。对于质量为10 GeV/c的WIMP，这种相互作用的特征能量为10 keV。一个合适的暗物质探测器必须有一个0.01 keV的阈值才是可行的。在太阳附近的暗星系晕的密度估计在0.3 GeV/ccm的数量级。将这个环境通量与超对称理论的理论WIMP-核子截面的上限10 - 41 cm 2结合起来，我们得到了极低的事件率10 - 1/千克/天。因此，合适的暗物质探测器还必须具有高度的背景抑制能力。本论文描述了这样一个探测器的发展，能够检测这些遗迹暗物质粒子。
There exists an overwhelming body of observational evidence that most of the matter in the universe is dark. The constraints of big bang nucleosynthesis coupled with lower limits on the matter density from dynamical estimates suggests that there exists large quantities of non-baryonic dark matter in the universe. In order to have avoided detection thus far, this new particle must interact only through the weak and gravitational forces. The presence of very old galaxies and clusters point strongly to a particle that was non-relativistic at the weak-scale decoupling time in the early universe. A well motivated candidate for this Weakly Interacting Massive Particle (WIMP) is a relic partner predicted from supersymmetric (SUSY) theories. If our Milky Way halo were composed of WIMPs, we expect them to be in a dissipationless, spherical distribution random Boltzmann velocities. A detector on the earth, carried through the galaxy at the orbital speed of the sun (∼ 300 km/s or 10−3c), could detect the recoil energy imparted by a WIMP scattering with one of its nuclei. Characteristic energies in this interaction would be ∼ 10 keV for WIMP masses of ∼ 10GeV/c. A suitable dark matter detector would have to have a threshold of ∼ 1 keV to be viable. Estimates of the density of the dark galactic halo in the solar neighborhood are on the order of 0.3 GeV/ccm. Combining this ambient flux with an upper limit of the theoretical WIMP-nucleon cross section from SUSY theory of ∼ 10−41cm2 gives us the extremely low event rates of ∼1 per kilogram per day. A suitable dark matter detector must therefor also have a high degree of background rejection capability. This thesis describes the development of such a detector capable of detecting these relic dark matter particles.