The MuCap experiment: A measurement of the muon capture rate in hydrogen gas
- Department of Physics, University of California, Berkeley, CA 94720 (United States)
We have recently measured the rate of nuclear muon capture by the proton, using a novel technique which involves a time projection chamber operating in ultraclean, deuterium-depleted hydrogen gas. The target's low gas density of 1% compared to liquid hydrogen is key to avoiding uncertainties that arise from the formation of muonic molecules. The capture rate from the hyperfine singlet ground state of the {mu}p atom was obtained from the difference between the {mu}{sup -} disappearance rate in hydrogen and the world average for the {mu}{sup +} decay rate, yielding {lambda}{sub S} = 725.0{+-}17.4 s{sup -1}, from which the induced pseudoscalar coupling of the nucleon, g{sub P}(q{sup 2} = 0.88m{sub {mu}}{sup 2}) = 7.3{+-}1.1, is extracted. This result is consistent with theoretical predictions for g{sub P} that are based on the approximate chiral symmetry of QCD.
- OSTI ID:
- 21036036
- Journal Information:
- AIP Conference Proceedings, Vol. 947, Issue 1; Conference: 7. Latin American symposium on nuclear physics and applications, Cusco (Peru), 11-16 Jun 2007; Other Information: DOI: 10.1063/1.2813810; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA). MuCap Collaboration; ISSN 0094-243X
- Country of Publication:
- United States
- Language:
- English
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