Decay of negative muons bound in Al-27 Academic Article uri icon


  • We present the first measurement of the energy spectrum up to 70 MeV of electrons from the decay of negative muons after they become bound in Al27 atoms. The data were taken with the TWIST apparatus at TRIUMF. We find a muon lifetime of (864.61.2)ns, in agreement with earlier measurements. The asymmetry of the decay spectrum is consistent with zero, indicating that the atomic capture has completely depolarized the muons. The measured momentum spectrum is in reasonable agreement with theoretical predictions at the higher energies, but differences around the peak of the spectrum indicate the need for O() radiative corrections to the calculations. The present measurement is the most precise measurement of the decay spectrum of muons bound to any nucleus. 2009 The American Physical Society.

published proceedings


author list (cited authors)

  • Grossheim, A., Bayes, R., Bueno, J. F., Depommier, P., Faszer, W., Fujiwara, M. C., ... Tribble, R. E.

citation count

  • 15

complete list of authors

  • Grossheim, A||Bayes, R||Bueno, JF||Depommier, P||Faszer, W||Fujiwara, MC||Gagliardi, CA||Gill, DR||Gumplinger, P||Hasinoff, MD||Henderson, RS||Hillairet, A||Hu, J||Koetke, DD||Marshall, GM||Mathie, EL||Mischke, RE||Olchanski, K||Olin, A||Openshaw, R||Poutissou, J-M||Poutissou, R||Selivanov, V||Sheffer, G||Shin, B||Stanislaus, TDS||Tacik, R||Tribble, RE

publication date

  • September 2009