Operation and fabrication of large mass superheated droplet detectors for dark matter search

by Viktor Zacek (Université de Montréal)

Friday 1 Feb 2002, 11:00 → 12:00 Europe/Zurich

13/2-005 (CERN)

The nature of the main constituents of the mass of the Universe is one of the outstanding riddles of cosmology and astro-particle physics and the supersymmetric neutralino is one of the most promising candidates. Many groups are presently engaged in direct dark matter search experiments and try to detect neutralino scattering via the detection of the small nuclear recoils expected in the energy range from 5 to 50 keV. PICASSO is a new approach for the detection of neutralino induced recoils and is based on the metastability of liquid droplets in the moderately superheated state. This method relies on the fact that for suitable operating parameters a liquid to vapor phase transition can be triggered exclusivley by heavily ionising particles and not by minimum ionising particles and a phase transition event is detected by piezo-electric transducers. This technique has the potential of a substantial increase in sensitivity and allows the construction of a large mass dark matter detector at modest cost. We present detectors produced by the PICASSO collaboration and discuss their fabrication, acoustic signal detection, noise identification and rejection, as well as other applications of this technique in fields like neutron and medical physics.

Organiser(s): Ariella Cattai / EP Division