Recent Results and Prospects on Superheated Superconducting Granules Detectors.

摘要

The basic properties of superheated superconducting granules (SSG) detectors are reviewed. Recent results are presented and discussed. Granule samples of different sizes (10 (mu)m 450 mK) show the absence of avalanche effect (seen by other authors in different conditions) for several samples of tin granules. A theoretical discussion of the avalanche effect is presented. The understanding of the role of heat exchanges in the composite medium leads to the concept of 'localized micro-avalanche' and opens the way to drastic improvements of SSG performance for particle detection. Such a phenomenon should be obtained by a better thermal matching between dielectric and granules, working at temperatures where the released latent heat is slightly positive. Estimates of the behavior of the detector at very low T are also given, where a thin layer of normal electrons near the surface is shown to contribute to the heat capacity of a superheated granule. We discuss the main points to be studied in the near future, and give a brief evaluation of the present status of feasibility investigation for several proposed experiments (solar neutrinos, monopoles, dark matter, double.