MUON-CATALYZED FUSION IN 3-K SOLID DEUTERIUM

Muon catalyzed fusion in deuterium traditionally has been studied in g aseous and liquid targets. The TRIUMF solid-hydrogen-layer target syst em has been used to study the fusion reaction rates in the solid phase of D-2 at a target temperature of 3 K. Products of two distinct branc hes of the reaction were observed: neutrons by a liquid organic scinti llator and protons by a silicon detector located inside the target sys tem. The effective molecular formation rate from the upper hyperfine s tate of mu d and the hyperfine transition rate have been measured: <(l ambda)over tilde> 3/2 = 2.71(7)(stat)(32)(syst)mu s(-1) and <(lambda)o ver tilde> 31/22 = 34.2(8)(stat)(1)(syst)mu s(-1). The molecular forma tion rate is consistent with other recent measurements, but not with t he theory for isolated molecules. The discrepancy may be due to incomp lete thermalization, an effect that was investigated by Monte Carlo ca lculations. Information on branching ratio parameters for the s and p wave d+d nuclear interaction has been extracted.