New constraints on WIMPS from the Canfranc IGEX dark matter search

摘要

The IGEX Collaboration enriched Ge-76 double-beta decay detectors are currently operating in the Canfranc Underground Laboratory with an overburden of 2450 m.w.e. A recent upgrade has made it possible to use them in a search for WIMPs. A new exclusion plot, sigma(m), has been derived for WIMP-nucleon spin-independent interaction. To obtain this result, 30 days of data from one IGEX detector, which has an energy threshold E-thr similar to 4 keV, have been considered. These data improve the exclusion limits derived from other ionization (non-thermal) germanium detector experiments in the similar to 50 GeV DAMA region, and show that with a moderate improvement of the background below 10 keV, the DAMA region may be tested with an additional 1 kg-year of exposure. (C) 2000 Elsevier Science B.V. All rights reserved. [References: 20]