A MICROWAVE MU-SR SPECTROMETER

A microwave-muSR (muWmuSR) spectrometer has been developed which opera tes in the frequency region of 1-2 GHz. The spectrometer geometry is t hat of longitudinal field (LF) muSR and is typically used in time inte gral measurements. The high frequency of this instrument distinguishes it from the currently used RFmuSR spectrometers and allows high field measurements to be made for normal Mu type systems. This allows one t o avoid low field broadening mechanisms that may be present, either fr om electronic spin-lattice relaxation or nuclear hyperfine interaction s. Technical details of the tunable microwave cavity and the RF coupli ng scheme are presented. Experimental spectra of Mu lines in SiO2 and GaAs are displayed.