“…Alternatively, in samples where it can bind to an electron to form muonium (Mu), the muonium can act as a light hydrogen-like probe that can be studied with the lSR technique. Over the past 10 years there has been a significant effort to develop an efficient method of LE-l + generation from the surface muon beams with kinetic energies around 4 MeV available at various muon facilities [3][4][5][6][7].…”