Observation of unexpected density effects in muon-catalyzed d-t fusion

Abstract
New experimental results on muon-catalyzed d-t fusion are reported. Unexpected target-density effects have been discovered both in dtμ molecular formation in tμ+D2 collisions and in the effective sticking probability. The dtμ formation rate is significantly enhanced at high density, presumably because of a strong three-body contribution. The origin of the observed reduction of the sticking probability at high density remains unclear. Both effects increase the number of fusions per muon that can be achieved; 150±4(stat.)±20(syst.) fusions per muon have been observed.