|
|||||
|
|
Measurement of the positive muon lifetime and determination of the Fermi constant to part-per-million precision |
|
| Authors: | Webber D M Tishchenko V Peng Q Battu S Carey R M Chitwood D B Crnkovic J Debevec P T Dhamija S Earle W Gafarov A Giovanetti K Gorringe T P Gray F E Hartwig Z Hertzog D W Johnson B Kammel P Kiburg B Kizilgul S Kunkle J Lauss B Logashenko I Lynch K R McNabb R Miller J P Mulhauser F Onderwater C J G Phillips J Rath S Roberts B L Winter P Wolfe B;MuLan Collaboration |
| Institution: | Department of Physics, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801, USA. |
| Abstract: | We report a measurement of the positive muon lifetime to a precision of 1.0 ppm; it is the most precise particle lifetime ever measured. The experiment used a time-structured, low-energy muon beam and a segmented plastic scintillator array to record more than 2×10(12) decays. Two different stopping target configurations were employed in independent data-taking periods. The combined results give τ(μ(+)) (MuLan)=2?196?980.3(2.2) ps, more than 15 times as precise as any previous experiment. The muon lifetime gives the most precise value for the Fermi constant: G(F) (MuLan)=1.166?378?8(7)×10(-5) GeV(-2) (0.6 ppm). It is also used to extract the μ(-)p singlet capture rate, which determines the proton's weak induced pseudoscalar coupling g(P). |
| Keywords: | |
| 本文献已被 PubMed 等数据库收录！ | |