Research objectives and content
Metastable systems are presently being applied to particle detection, promising important improvements in special applications such as astroparticle or neutrino physics. We will study three such types of devices: collections of metastable microspheres, thin metastable strips, and dispersions of droplets of a superheated liquid. We plan to use superconducting Rhenium strips for searches of a non-zero neutrino mass signature in the spectrum of Rhenium's beta decay. In parallel to this, the microspheres will be used for a Dark Matter (DM) experiment to be installed in an European underground laboratory (Canfranc, Spanish Pyrenees). This detector's background rejection ability is expected to improve the present sensitivity to galactic particle DM. At the same time, a microsphere-based Transition Radiation detector (developed in collaboration with Taiwan) will be tested in an European high-energy electron beam. Finallyw last year we embarked in the development of Superheated Droplet Detectors (SDD) for panicle DM detection, an approach proposed by the applicant [ 11. These devices are expected to improve the present sensitivity to putative DM particles composing the galactic halo (WIMPS) by several orders of magnitude. During the length of this program a dedicated. large mass SDD will be built. tested and installed underground.
[ll J.l. Collar, Phys. Rev. D 54 (1996) 1247.
Training content (objective, benefit and expected impact)
My experience in the fields of DM phenomenology, low background techniques, neutrino physics and radiation effects will be applied to these programs; in exchange I will receive a complementary education in superconductivity, cryogenic techniques, condensed matter and polymer science. In this sense the program offers a unique opportunity for the broadening of my profesional experience and education, since I will be a nuclear physicist working in a solid state group. The benefits are symbiotic.
Links with industry / industrial relevance (22)
Of particular importance (see attached proposal) will be the improvements required for the application of SDDs in dark matter searches. Present SDDs, commercialized as neutron detectors (in Europe by SIEMENS), have a listed shelf-life of just a few months. We intend, by improving the matrix gel, to extend this to several years in our SDDs, which should revert back to the industrial refinement of these devices (SDDs are acquiring prominence and acceptation as ideal neutron dosimeters).