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Title: Search for Lepton Flavor Violation in the Decay {tau}{sup {+-}}{yields}e{sup {+-}}{gamma}

Abstract

A search for the nonconservation of lepton flavor in the decay {tau}{sup {+-}}{yields}e{sup {+-}}{gamma} has been performed with 2.07x10{sup 8} e{sup +}e{sup -}{yields}{tau}{sup +}{tau}{sup -} events collected by the BABAR detector at the SLAC PEP II storage ring at a center-of-mass energy near 10.58 GeV. We find no evidence for a signal and set an upper limit on the branching ratio of B({tau}{sup {+-}}{yields}e{sup {+-}}{gamma})<1.1x10{sup -7} at 90% confidence level.

Authors:
; ; ; ; ; ; ; ;  [1];  [2]; ; ;  [3]; ; ; ; ;  [4]; ;  [5]
  1. Laboratoire de Physique des Particules, F-74941 Annecy-le-Vieux (France)
  2. IFAE, Universitat Autonoma de Barcelona, E-08193 Bellaterra, Barcelona (Spain)
  3. Dipartimento di Fisica and INFN, Universita di Bari, I-70126 Bari (Italy)
  4. Institute of High Energy Physics, Beijing 100039 (China)
  5. Institute of Physics, University of Bergen, N-5007 Bergen (Norway) (and others)
Publication Date:
OSTI Identifier:
20777004
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review Letters; Journal Volume: 96; Journal Issue: 4; Other Information: DOI: 10.1103/PhysRevLett.96.041801; (c) 2006 The American Physical Society; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; ANNIHILATION; BRANCHING RATIO; CONSERVATION LAWS; ELECTRON-POSITRON INTERACTIONS; ELECTRONS; FLAVOR MODEL; GEV RANGE 10-100; MASS; PARTICLE DECAY; POSITRONS; SIGNALS; STANFORD LINEAR ACCELERATOR CENTER; TAU PARTICLES; VIOLATIONS

Citation Formats

Aubert, B., Barate, R., Boutigny, D., Couderc, F., Karyotakis, Y., Lees, J.P., Poireau, V., Tisserand, V., Zghiche, A., Grauges, E., Palano, A., Pappagallo, M., Pompili, A., Chen, J.C., Qi, N.D., Rong, G., Wang, P., Zhu, Y.S., Eigen, G., and Ofte, I. Search for Lepton Flavor Violation in the Decay {tau}{sup {+-}}{yields}e{sup {+-}}{gamma}. United States: N. p., 2006. Web. doi:10.1103/PhysRevLett.96.041801.
Aubert, B., Barate, R., Boutigny, D., Couderc, F., Karyotakis, Y., Lees, J.P., Poireau, V., Tisserand, V., Zghiche, A., Grauges, E., Palano, A., Pappagallo, M., Pompili, A., Chen, J.C., Qi, N.D., Rong, G., Wang, P., Zhu, Y.S., Eigen, G., & Ofte, I. Search for Lepton Flavor Violation in the Decay {tau}{sup {+-}}{yields}e{sup {+-}}{gamma}. United States. doi:10.1103/PhysRevLett.96.041801.
Aubert, B., Barate, R., Boutigny, D., Couderc, F., Karyotakis, Y., Lees, J.P., Poireau, V., Tisserand, V., Zghiche, A., Grauges, E., Palano, A., Pappagallo, M., Pompili, A., Chen, J.C., Qi, N.D., Rong, G., Wang, P., Zhu, Y.S., Eigen, G., and Ofte, I. Fri . "Search for Lepton Flavor Violation in the Decay {tau}{sup {+-}}{yields}e{sup {+-}}{gamma}". United States. doi:10.1103/PhysRevLett.96.041801.
@article{osti_20777004,
title = {Search for Lepton Flavor Violation in the Decay {tau}{sup {+-}}{yields}e{sup {+-}}{gamma}},
author = {Aubert, B. and Barate, R. and Boutigny, D. and Couderc, F. and Karyotakis, Y. and Lees, J.P. and Poireau, V. and Tisserand, V. and Zghiche, A. and Grauges, E. and Palano, A. and Pappagallo, M. and Pompili, A. and Chen, J.C. and Qi, N.D. and Rong, G. and Wang, P. and Zhu, Y.S. and Eigen, G. and Ofte, I.},
abstractNote = {A search for the nonconservation of lepton flavor in the decay {tau}{sup {+-}}{yields}e{sup {+-}}{gamma} has been performed with 2.07x10{sup 8} e{sup +}e{sup -}{yields}{tau}{sup +}{tau}{sup -} events collected by the BABAR detector at the SLAC PEP II storage ring at a center-of-mass energy near 10.58 GeV. We find no evidence for a signal and set an upper limit on the branching ratio of B({tau}{sup {+-}}{yields}e{sup {+-}}{gamma})<1.1x10{sup -7} at 90% confidence level.},
doi = {10.1103/PhysRevLett.96.041801},
journal = {Physical Review Letters},
number = 4,
volume = 96,
place = {United States},
year = {Fri Feb 03 00:00:00 EST 2006},
month = {Fri Feb 03 00:00:00 EST 2006}
}
  • A search for the nonconservation of lepton flavor number in the decay {tau}{sup {+-}}{yields}{mu}{sup {+-}}{gamma} has been performed using 2.07x10{sup 8} e{sup +}e{sup -}{yields}{tau}{sup +}{tau}{sup -} events produced at a center-of-mass energy near 10.58 GeV with the BABAR detector at the PEP-II storage ring. We find no evidence for a signal and set an upper limit on the branching ratio of B({tau}{sup {+-}}{yields}{mu}{sup {+-}}{gamma})<6.8x10{sup -8} at 90% confidence level.
  • A search for lepton-flavor and lepton-number violation in the decay of the tau lepton into one charged lepton and two charged hadrons is performed using 221.4 fb{sup -1} of data collected at an e{sup +}e{sup -} center-of-mass energy of 10.58 GeV with the BABAR detector at the SLAC PEP-II storage ring. In all 14 decay modes considered, the observed data are compatible with background expectations, and upper limits are set in the range B({tau}{yields}lhh{sup '})<(0.7-4.8)x10{sup -7} at 90% confidence level.
  • A search for lepton-flavor-violating process e{sup +}e{sup -{yields}}e{mu} in the energy region {radical}(s)=984-1060 MeV with the SND detector at the VEPP-2M e{sup +}e{sup -} collider is reported. The model independent 90% C.L. upper limits on the e{sup +}e{sup -{yields}}e{mu} cross section, {sigma}{sub e{mu}<}8 pb, as well as on the corresponding {phi}{yields}e{mu} branching fraction, B({phi}{yields}e{mu})<2x10{sup -6} have been obtained, for the polar angles 55 deg. <{theta}<125 deg. of the final particles.
  • Searches for lepton-flavor-violating decays of a {tau} lepton to a lighter mass lepton and a photon have been performed with the entire data set of (963+-7)x10{sup 6} {tau} decays collected by the BABAR detector near the {Upsilon}(4S), {Upsilon}(3S) and {Upsilon}(2S) resonances. The searches yield no evidence of signals and we set upper limits on the branching fractions of B(tau{sup +}-->e{sup +}-{gamma})<3.3x10{sup -8} and B({tau}{sup +}-->{mu}{sup +}-{gamma})<4.4x10{sup -8} at 90% confidence level.
  • A search for the non-conservation of lepton flavor in the decay {tau}{sup {+-}} {yields} e{sup {+-}}{gamma} has been performed with 2.07 x 10{sup 8} e{sup +}e{sup -} {yields} {tau}{sup +}{tau}{sup -} events collected by the BABAR detector at the PEP-II storage ring at a center-of-mass energy near 10.58 GeV. They find no evidence for a signal and set an upper limit on the branching ratio of {Beta}({tau}{sup {+-}} {yields} e{sup {+-}}{gamma}) < 1.1 x 10{sup -7} at 90% confidence level.