One of the major questions in modern astrophysics is the dark matter problem. Even though there is little to no doubt that darkmatter exists, it is still not yet known what dark matter is made of. Cosmology provides evidence that the dark matter contains a non-baryoniccomponent. One possible candidate is the existence of weakly interacting massive particles (WIMPs).
This work describes how WIMPs can be detected and what signal type and range can be expected of them. With the expectable low countrate of WIMPs it becomes obvious that the main constraint for recording a dark-matter event is the background of the WIMP signature. Onepossible detector for such a WIMP experiment can be a lithium drifted silicon detector in which a WIMP interaction generates a nuclearrecoil of a silicon atom which produces a detector signal. Los Alamos National Laboratory (LANL) can potentially get more than 650 lithiumdrifted silicon detectors with a mass of 100 grams each. Three prototypes of these detectors have been tested to determine the quality of thematerial and to check their intrinsic background. The results of these tests are documented here.
A possible underground laboratory candidate for these measurement is the waste isolation pilot plant (WIPP) near Carlsbad (New Mexico). Thisthesis describes the setup of the underground site as well as the background measurements conducted for the gamma and muonbackground. Several measurements of the gamma background with different shielding material have been done and the results arediscussed in detail. The results of the gamma measurements show that the gamma background can be reduced by a factor of 927 with thecurrent shielding material and the underground location.
Since the muons represent the only radiation that cannot be blocked by passive shielding in the underground their flux and inducedbackground is of high importance to all low background experiments. The muon flux is measured with a quadrupel coincidence scintillatordetector. An estimate for the muon induced background is discussed.
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