A search for. nu. sub e appearance from stopped. pi. sup + and. mu. sup + decay at LAMPF (Los Alamos Meson Physics Facility)

Technical Report · Mon Jan 01 00:00:00 EST 1990

DOI:https://doi.org/10.2172/5093548· OSTI ID:5093548

Fujikawa, B K ^[1]

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1. California Inst. of Tech., Pasadena, CA (USA). Dept. of Physics

We report on a recent search for {bar {nu}}{sub e} appearance from stopped {pi}{sup +} {yields} {mu}{sup +}{nu}{sub {mu}} and {mu}{sup +} {yields} e{sup +}{nu}{sub e}{bar {nu}}{sub {mu}} decay made by the LAMPF experiment E645. The appearance of {bar {nu}}{sub e} may occur from {bar {nu}}{sub {mu}} {yields} {bar {nu}}{sub e}, {nu}{sub e} {yields} {bar {nu}}{sub eL}, or {nu}{sub {mu}} {yields} {bar {nu}}{sub eL} oscillations. Appearance may also occur from rare {mu}{sup +} {yields} e{sup +}{bar {nu}}{sub e}{nu}{sub {mu}} decay, which is allowed by a multiplicative lepton charge conservation law. The neutrino energies range from E{sub {nu}} = 0 to 52.8MeV. The neutrino detector, which is located 26.1 meters from the neutrino source, consists of a segmented liquid scintillator and proportional drift tube central detector surrounded by both active and passive shielding. The central detector detects {bar {nu}}{sub e} through the {bar {nu}}{sub e}p {yields} ne{sup +} Charge Current (CC) reaction, which is signaled by the direct detection of the final state positron and neutron. The hydrogen-rich liquid scintillators act as free proton targets for the {bar {nu}}{sub e}p CC reaction. The neutrons are detected through radiative neutron capture on gadolinium. We find no evidence for {bar {nu}}{sub e} appearance in the first year of running. New limits on the {bar {nu}}{sub {mu}},{nu}{sub e},{nu}{sub {mu}} {yields} {bar {nu}}{sub e} oscillation parameters and the rare {mu}{sup +} {yields} e{sup +}{bar {nu}}{sub e}{nu}{sub {mu}} decay branching ratio are presented. 87 refs., 45 figs., 17 tabs.

• Research Organization: Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
• Sponsoring Organization: DOE/ER
• DOE Contract Number: W-7405-ENG-36
• OSTI ID: 5093548
• Report Number(s): LA-11721-T; ON: DE90005833; TRN: 90-003534
• Resource Relation: Other Information: Thesis (Ph.D.). Thesis. Submitted to California Institute of Technology, Pasadena, California
• Country of Publication: United States
• Language: English

Related Subjects

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS
MUONS PLUS
PARTICLE DECAY
PIONS PLUS
BRANCHING RATIO
CAPTURE
CONSERVATION LAWS
ELECTRON ANTINEUTRINOS
EXPERIMENTAL DATA
GADOLINIUM
LEPTON NUMBER
LIQUID SCINTILLATORS
MEV RANGE 10-100
NEUTRINO DETECTION
NEUTRON REACTIONS
PROPORTIONAL COUNTERS
ANTILEPTONS
ANTIMATTER
ANTINEUTRINOS
ANTIPARTICLES
BARYON REACTIONS
BOSONS
DATA
DECAY
DETECTION
ELECTRON NEUTRINOS
ELEMENTARY PARTICLES
ELEMENTS
ENERGY RANGE
FERMIONS
HADRON REACTIONS
HADRONS
INFORMATION
LEPTONS
MASSLESS PARTICLES
MEASURING INSTRUMENTS
MESONS
METALS
MEV RANGE
MUONS
NEUTRINOS
NUCLEAR REACTIONS
NUCLEON REACTIONS
NUMERICAL DATA
PHOSPHORS
PIONS
PSEUDOSCALAR MESONS
RADIATION DETECTION
RADIATION DETECTORS
RARE EARTHS
645102* - High Energy Physics- Particle Interactions & Properties-Experimental- Weak Interactions & Properties