Progress report on recent rare muon decay experiments at the Los Alamos Meson Physics Facility

Conference · Sun Jan 01 00:00:00 EST 1984

DOI:https://doi.org/10.1016/0375-9474(85)90516-0· OSTI ID:6304484

Hogan, G E; Bolton, R D; Bowman, J D; Carlini, R; Cooper, M D; Duong-van, M; Frank, J S; Hallin, A L; Heusi, P; Hoffman, C M

A search has been performed for the decays ..mu.. ..-->.. eee, ..mu.. ..-->.. e..gamma.., and ..mu.. ..-->.. e..gamma gamma.. with a sensitivity in the branching ratios at the level of 10/sup -10/. The experiment used a separated, 26 MeV/c ..mu../sup +/ beam with an average intensity of 300kHz. A total of 2.2 x 10/sup 11/ muon decays were examined for the present result. The detector for the experiment is the Crystal Box, which consists of a cylindrical drift chamber surrounded by 396 NaI(T1) crystals. A layer of scintillation counters in front of the crystals provided timing for electrons and veto for photons. The energy resolution for electrons and photons is approx. 6% (FWHM). The position resolution of the drift chamber is 350 ..mu..m leading to a vertex cut with a rejection of 10/sup 3/ for ..mu.. ..-->.. eee. The timing resolution is approx. 300 ps the scintillators and approx. 1 ns from the crystals. No candidate for ..mu.. ..-->.. eee has been found, yielding an upper limit for the branching ratio of B/sub ..mu..3e/ < 1.3 x 10/sup -10/ (90% C.L.). 21 references.

• Research Organization: Los Alamos National Laboratory (LANL), Los Alamos, NM (United States); Stanford Univ., CA (United States); Univ. of Chicago, IL (United States); Temple Univ., Philadelphia, PA (USA)
• DOE Contract Number: W-7405-ENG-36; AC02-76ER03539
• OSTI ID: 6304484
• Report Number(s): LA-UR-84-2411; COO-3539-27; CONF-840789-4; ON: DE85001503
• Resource Relation: Journal Volume: 434; Conference: International conference on particles and nuclei, Heidelberg, F.R. Germany, 30 Jul 1984; Other Information: Portions are illegible in microfiche products
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
MUONS PLUS
WEAK PARTICLE DECAY
BRANCHING RATIO
DRIFT CHAMBERS
ELECTRONS
LEPTON NUMBER
MUON NUMBER
PHOTONS
ANTILEPTONS
ANTIMATTER
ANTIPARTICLES
DECAY
ELEMENTARY PARTICLES
FERMIONS
LEPTONS
MASSLESS PARTICLES
MEASURING INSTRUMENTS
MULTIWIRE PROPORTIONAL CHAMBERS
MUONS
PARTICLE DECAY
PROPORTIONAL COUNTERS
RADIATION DETECTORS
645102* - High Energy Physics- Particle Interactions &amp; Properties-Experimental- Weak Interactions &amp; Properties