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Search for the neutrinoless muon decay. mu. /sup +/. -->. e/sup +/. gamma

Description: Separate muon, electron, and tau numbers are conserved in the minimal standard model of electroweak interactions with massless neutrinos. However, in many extensions to the standard model, separate lepton numbers are not expected to be conserved quantities. A new search for muon number non-conserving processes has been undertaken at the Los Alamos Meson Physics Facility (LAMPF), specifically to look for three neutrinoless decay modes of the muon. The search for the decay of a muon to an electro… more
Date: July 1, 1985
Creator: Wilson, S.L.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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The neutrinos in muon decay

Description: We review the available information on the identity of the neutrino states emitted in muon decay, and discuss the exotic decay {mu}{sup +} {yields} e{sup +} {bar {nu}}{sub e}{nu}{sub {mu}}. 22 refs.
Date: October 21, 1991
Creator: Herczeg, P.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Proposal to assemble a high resolution-electron sensitive-energy flow calorimeter in the NEULAND spectrometer

Description: A ..gamma.. catcher and a liquid scintillation calorimeter module in a simple configuration that is well suited to the investigation of several different neutrino induced processes are described. The variety of neutrino beams now available at Fermilab and synchrotron intensity and energy together with the high resolution calorimeter allow a multiplicity of experiments to be carried out with a single detector configuration.
Date: January 1, 1977
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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High resolution positron Q-value measurements and nuclear structure studies far from the stability line. Progress report

Description: Research progress in briefly described, and details are presented in the attached preprints and reprints: (1) precision mass differences in light rubidium and krypton isotopes utilizing beta endpoint measurements; (2) precision mass measurements utilizing beta endpoints; (3) Monte Carlo calculations predicting the response of intrinsic GE detectors to electrons and positrons; and (4) reactor antineutrino spectra and nuclear spectroscopy of isotopes far from beta stability. (WHK)
Date: February 28, 1982
Creator: Avignone, F. T. III
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Measurement of sin/sup 2/theta/sub w/ in Semileptonic nu Fe and anti nu Fe Interactions

Description: We report results from neutral current scattering of muon neutrinos and antineutrinos on iron nuclei by the CCFRR experiment at Fermilab. Our objective is the measurement of sin/sup 2/theta/sub w/ from inclusive semileptonic neutrino-nucleon interactions. Such a measurement, even though it is subject to more corrections than the analogous measurement in neutrino-electron scattering (e.g. due to the presence of a strange quark sea in the nucleon), has a high degree of statistical accuracy and ma… more
Date: October 1983
Creator: Blair, R. E.; MacFarlane, D. B.; Messner, R. L.; Novikoff, D. B.; Purohit, M. V.; Merritt, F. S. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Temperature dependence of the fraction of re-emitted positrons, the positron work function, and the positronium fraction for Cu(III)+S

Description: A beam of 1 keV positrons incident on a Cu(111)+S surface has been used to study the dependence on temperature of the positron work function (phi/sub +/), the yield of re-emitted positrons (Y) and of the positronium (Ps) fraction. A positive dependence of the slow-positron yield on temperature is found which is attributed in part to a reduction in the magnitude of phi/sub +/ (approx. 25%) at 50 K relative to its value at 300 K. A similar, though weaker, positive dependence on temperature was se… more
Date: January 1, 1982
Creator: Schultz, P.J. & Lynn, K.G.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Quantum mechanical theory of positron production in heavy ion collisions with nuclear contact

Description: The interplay between atomic and nuclear interactions in heavy ion collisions with nuclear contact is studied. The general theoretical description is outlined and analyzed in a number of different limits (semiclassical approximation, DWBA, fully quantal description). The two most important physical mechanisms for generating atomic-nuclear interference, i.e., energy conservation and the introduction of additional phase shifts by nuclear reactions, are extracted. The resulting typical coupling ma… more
Date: January 1, 1986
Creator: Heinz, U.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Positive muon and the positron as probes of defects

Description: The positive muon and the positron are each being used nowadays to investigate defects in condensed matter. A brief summary of the experimental methods employed with each particle is given in this paper. Similarities and differences between the behavior of the two leptons when implanted in consensed matter are pointed out, and by means of a comparison between muon and positron data in Al it is shown that the combination of muon and positron experiments can serve as a useful new probe of defects… more
Date: January 1, 1980
Creator: Lynn, K G
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A search for. nu. sub e appearance from stopped. pi. sup + and. mu. sup + decay at LAMPF (Los Alamos Meson Physics Facility)

Description: 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 … more
Date: January 1, 1990
Creator: Fujikawa, B. K.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Limit on the Anti Nu/sub E/ Mass in Free Molecular Tritium Beta Decay

Description: The beta spectrum of the decay of free molecular tritium has been accurately measured in order to search for a finite anti nu/sub e/ mass. The final state effects in molecular tritium are accurately known and the data thus yield an essentially model independent upper limit of 29 eV on the anti nu/sub e/ mass at the 95% confidence level. 17 refs., 4 figs., 1 tab.
Date: January 1, 1986
Creator: Bowles, T. J.; Browne, J. C.; Maley, M. P.; Robertson, R. G. H.; Wilkerson, J. F.; Knapp, D. A. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Muon Diffusion in Noble Metals

Description: Diffusion-induced muon depolarization was measured in dilute AgGd and AgEr in the temperature range 200 to 700/sup 0/K and have thereby determined the muon diffusion parameters in Ag. The diffusion parameters for ..mu../sup +/ in Cu, Ag, and Au are compared with those of hydrogen. For Ag and Au, the ..mu../sup +/ parameters are similar to those of hydrogen, whereas for Cu, the ..mu../sup +/ parameters are much smaller. Lattice-activated tunneling and over-barrier hopping are investigated with c… more
Date: January 1, 1982
Creator: Schillaci, M. E.; Boekema, C.; Heffner, R. H.; Hutson, R. L.; Leon, M.; Olsen, C. E. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Tests of perturbative quantum chromodynamics in photon-photon collisions

Description: The production of hadrons in the collision of two photons via the process e/sup +/e/sup -/ ..-->.. e/sup +/e/sup -/X can provide an ideal laboratory for testing many of the features of the photon's hadronic interactions, especially its short-distance aspects. That part of two-photon physics which is particularly relevant to tests of perturbative QCD is reviewed here. 6 figures.
Date: January 1, 1979
Creator: Brodsky, Stanley J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Positron lifetimes in solids from first principles calculations

Description: We present a first principles method for calculating positron lifetimes in solids, based on self-consistent calculations using the Linear Muffin-Tin Orbital method. Local density approximations are used for both electron-electron and electron-positron interactions. Results are presented for a variety of elemental metals and vacancies to demonstrate the reliability of this approach. Theoretical calculations of positron lifetimes can be used to interpret experimental data. As an examples of this,… more
Date: August 7, 1991
Creator: Sterne, P. A.; O'Brien, J. C.; Howell, R. H. & Kaiser, J. H.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Experiment to study the. beta. -decay of free atomic and molecular tritium. [For determining antineutrino mass]

Description: An apparatus is described which will allow the measurement of the ..beta..-decay of free tritium atoms and molecules for determining antineutrino mass. It consists of an RF dissociator, a long cylindrical decay region open at both ends, a guide field, and a magnetic spectrometer.
Date: January 1, 1982
Creator: Robertson, R. G. H.; Bowles, T. J.; Maley, M.; Browne, J. C.; Burritt, T.; Toevs, J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Variable-energy positron studies of well-annealed single-crystal Cd samples from 35 to 450 K

Description: Well-annealed Cd(001) and Cd(100) samples have been examined using a monoenergetic variable-energy positron beam (0.5 to 5.0 keV). The results are interpreted in the context of a one-dimensional-diffusion model which allows for annihilations as well as trapping at defects including thermally generated vacancies. The dependence on temperature of positron diffusion out of these samples was determined by the use of this model to interpret data taken between 35 and 450 K. The deduced positron diffu… more
Date: January 1, 1982
Creator: Lynn, K.G.; Goland, A.N.; Schultz, P.J.; Vehanen, A. & MacKenzie, I.K.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Muonium to antimuonium conversion and the decay. mu. sup + yields e sup +. nu. sub e. nu. sub. mu. in left-right symmetric models

Description: We investigate muonium to antimuonium conversion and the exotic muon decay {mu}{sup +} {r arrow} e{sup +}{bar {upsilon}}{sub e} {epsilon}{sub {mu}} in SU(2){sub L} {times} SU(2){sub R} {times} U(1){sub B-L} models. 7 refs.
Date: January 1, 1991
Creator: Herczeg, P. (Los Alamos National Lab., NM (United States)) & Mohapatra, R.N. (Maryland Univ., College Park, MD (United States). Dept. of Physics and Astronomy)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Phenomenology of New Particle Production in Heavy-Ion Collisions

Description: It is shown that the existence of sharp lines in the positron emission spectra observed in low-energy heavy-ion collisions is consistent with the production and subsequent decay of a neutral, pseudoscalar particle with a mass of about 1.6 MeV and a lifetime of about 10/sup -13/ sec. 19 refs., 2 figs.
Date: January 1, 1985
Creator: Balantekin, A. B.; Bottcher, C.; Strayer, M. R. & Lee, S. J.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Surface areas by positron annihilation spectroscopy

Description: Positron annihilation spectroscopy (PAS) is a technique for measuring the length of time that a positron exists after being injected into a specific material. Lifetime measurements have been used for studying defects in metals. These imperfections affect the localized electron densities which in turn influence the lifetime of the positron before annihilation occurs. Electron density differences are also associated with surfaces. This paper describes the PAS technique and shows a correlation bet… more
Date: January 1, 1985
Creator: Dale, J.M.; Rosseel, T.M.; Hulett, L.D.; Venkateswaran, K.; Jean, Y.C. & Fuller, E.L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Theory of the temperature dependence of positron bulk lifetimes-implications for vacancy formation enthalpy measurements via positron experiments

Description: Temperature dependent effects, which may have a bearing on determinations of vacancy formation enthalpies in metals by positron annihilation, have been observed in certain metals. These effects have been observed to occur both at temperatures below those at which positron annihilation is most sensitive to equilibrium vacancies and at temperatures well within the vacancy-sensitive region. The effect of thermal lattice displacements on positron lifetimes in metals was investigated to help underst… more
Date: February 1, 1977
Creator: Tam, S.W.; Sinha, S.K. & Siegel, R.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Zero-field. mu. SR and low-temperature. mu. /sup +/ diffusivity in copper

Description: In this paper the history of ..mu../sup +/ diffusion studies in copper, with particular emphasis on the increased low-temperature diffusivity which has been known for several years now, is reviewed. The theory and practice of the zero-field ..mu..SR method, which has come into increasing favor in the study of muon diffusion and trapping in metals, is surveyed, and its application to the low-temperature copper problem is discussed. 26 references.
Date: April 1, 1983
Creator: Clawson, C.W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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