Samuel Henry

Abstract:

EURECA (European Underground Rare Event Calorimeter Array) is a new project, searching for dark matter. The collaboration is comprised largely of the present groups of the CRESST and EDELWEISS experiments and several new groups. The aim is to explore scalar cross sections in the - 10 -9-10-10picobarn region with a target mass of up to one tonne. A major advantage of EURECA is the planned use of more that just one target material (multi target experiment for WIMP identification). In preparation for this largescale experiment, R&D for EURECA is provided through the current phases of CRESST and EDELWEISS.

Abstract:

The CRESST experiment is looking for non-baryonic particle dark matter via nuclear scattering in CaWO4. The simultaneous measurement of the heat and the scintillation light generated by an event in a CaWO4 single crystal is used to discriminate between electron and nuclear recoils thanks to their different light output. This allows an efficient suppression of the electron recoil background. The set-up consists of modules with a 300 g CaWO4 crystal mounted in a reflective housing together with a light detector. The heat signal is read out using a superconducting transition-edge sensor (TES) made of tungsten evaporated directly onto the crystal that is operated at a few mK. Currently the second phase of the experiment is being set up at the Laboratori Nazionali del Gran Sasso in which it is planned to run 33 detector modules providing a total target mass of 10 kg. First test runs with prototype detectors have been successfully performed.

Abstract:

We present first significant limits on WIMP dark matter by the phonon-light technique, where combined phonon and light signals from a scintillating cryogenic detector are used to suppress the non-nuclear recoil background. The performance of the detectors developed for the second phase of the CRESST experiment will be discussed and data collected with two prototype modules in a short run, corresponding to a net exposure of 20.5 kg days, will be presented. (c) 2005 Elsevier B.V. All rights reserved.