The experimental setup for measuring negative muon lifetime in xenon and krypton

The construction of a cryostat for measuring the nuclear capture rate of negative muons in condensed xenon and krypton is described. The experimental setup was tested in real conditions in the polarized muon beam of the phasotron of the Laboratory of Nuclear Problems of JINR. The natural mixture of xenon isotopes was used as a target. The mean lifetime of the negative muon in 1s-state in natural xenon was first measured. The lifetime τμ=95±7 ns corresponds to the nuclear capture rate Λc=(10,1±0,7)·106 s-1. (author)