Time-differential radio-frequency muon spin resonance (TD-RF mu SR) technique at a pulsed muon beam

Longitudinal-field mu SR methods, e.g., radio-frequency mu(+) spin resonance (RF mu SR), are well suited to investigate dynamic processes that destroy the phase coherence of the muon spin ensemble. Additional information on relaxation processes of the muon species under investigation is obtained from time-differential (TD) data acquisition. In this paper we describe the set-up of a TD-RF mu SR spectrometer installed at the ISIS pulsed muon facility at the Rutherford Appleton Laboratory (RAL, Chilton, UK). As an example, results of TD-RF mu SR measurements on muons in diamagnetic environment mu(d) in a boron-doped silicon sample under illumination at 55 K are presented.