Experimental investigation of muon-catalyzed dt fusion at cryogenic temperatures

An experimental investigation of muon-catalyzed fusion (mu CF) in gaseous, liquid and solid mixtures of deuterium and tritium was performed. The target conditions included the range of densities of 0.03 less than or similar to phi less than or similar to 1.5, tritium concentrations of 2% less than or similar to c(r) less than or similar to 90% and temperatures of 13 less than or similar to T less than or similar to 40K. The study was based on the analysis of observed cycling rates extracted from the measured time distributions of the fusion neutrons. For the first time, the density dependence of the rates lambda((dt mu)d)(0) for the dt mu molecule formation in collisions of t mu atoms in the lower (F=0) hyperfine state with D-2 molecules was determined experimentally. Evidence for the proposed effects of below-threshold resonances on molecular formation was found. Measurements at low temperatures in mixtures of different molecular compositions revealed a clear predominance of the lambda((dt mu)d)(0) formation rate. The probability q(1s) for d mu atoms to reach the ground state was determined as a function of density and tritium concentration. (C) 1999 Elsevier Science B.V. All rights reserved.