THE SEARCH FOR COLD NUCLEAR-FUSION WITH TRACK-ETCH AND BUBBLE DAMAGE DETECTORS

Recent reports of the observation of (D-D) fusion in deuterated transition metals (Pd, Ti) has stimulated intense interest in the verification of this process. A variety of different techniques for deuterium loading in metals (electrochemical charging, pressurization with D2 gas, ion implantation, ionized cluster beam method) and/or diagnostic methods for the energy, isotopes and radiation generated have been applied. Diagnostic methods based on the radiation generated comprise measurements of: i) fusion neutrons, fusion charged particles (p, H-3, He-3), ii) neutron-induced gamma-rays, and iii) charged particle induced X-rays. Various radiation detection systems, such as proportional counters (He-3,(BF3)-B-10), organic liquid (NE 213) and inorganic crystal (NaI) scintillators, solid state surface barrier detectors (Si), semiconductor gamma spectrometers (Ge), thermoluminescent dosimeters (CaF2), track-etch detectors (CR-39) and bubble damage detectors (BD-100), have been used. In the present paper diagnostic methods based on utilization of track-etch and bubble damage detectors for the detection of cold fusion in condensed matter are surveyed. The advantages of track-etch and bubble damage detectors in comparison with other radiation detectors arise from their ability to detect neutrons and charged particles; determine particle charge, energy, location and propagation direction; perform in-situ detection of fusion products inside condensed matter; carry out imaging and localization of the cold fusion sources; detect burst emission (no limitation by a finite response time) and integrate fluence during a long exposure time without an appreciable increase in the background. It was reported that the lowest detectable (D-D) fusion rate in condensed matter with CR-39 and BD-100 detectors is 10(-25) fusion/D-D pair.s-1. Extension of this value down to 10(-26) fusion/D-D pair.s-1 seems to be feasible.