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Title: Search for the decay B{sup +}{yields}{tau}{sup +}{nu}{sub {tau}}

Abstract

We search for the rare leptonic decay B{sup +}{yields}{tau}{sup +}{nu}{sub {tau}} in a sample of 232x10{sup 6} BB pairs collected with the BABAR detector at the SLAC PEP-II B-Factory. Signal events are selected by examining the properties of the B meson recoiling against the semileptonic decay B{sup -}{yields}D*{sup 0}l{sup -}{nu}{sub l}. We find no evidence for a signal and set an upper limit on the branching fraction of B(B{sup +}{yields}{tau}{sup +}{nu}{sub {tau}})<2.8x10{sup -4} at the 90% confidence level. We combine this result with a previous, statistically independent BABAR search for B{sup +}{yields}{tau}{sup +}{nu}{sub {tau}} to give an upper limit of B(B{sup +}{yields}{tau}{sup +}{nu}{sub {tau}})<2.6x10{sup -4} at the 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. Universita di Bari, Dipartimento di Fisica and INFN, I-70126 Bari (Italy)
  4. Institute of High Energy Physics, Beijing 100039 (China)
  5. University of Bergen, Institute of Physics, N-5007 Bergen (Norway) (and others)
Publication Date:
OSTI Identifier:
20776908
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physical Review. D, Particles Fields; Journal Volume: 73; Journal Issue: 5; Other Information: DOI: 10.1103/PhysRevD.73.057101; (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; B PLUS MESONS; BRANCHING RATIO; D*-2010 MESONS; LEPTONIC DECAY; MULTIPARTICLE SPECTROMETERS; PARTICLE IDENTIFICATION; PEP STORAGE RINGS; SEMILEPTONIC DECAY; TAU NEUTRINOS

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 the decay B{sup +}{yields}{tau}{sup +}{nu}{sub {tau}}. United States: N. p., 2006. Web. doi:10.1103/PhysRevD.73.057101.
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 the decay B{sup +}{yields}{tau}{sup +}{nu}{sub {tau}}. United States. doi:10.1103/PhysRevD.73.057101.
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. Wed . "Search for the decay B{sup +}{yields}{tau}{sup +}{nu}{sub {tau}}". United States. doi:10.1103/PhysRevD.73.057101.
@article{osti_20776908,
title = {Search for the decay B{sup +}{yields}{tau}{sup +}{nu}{sub {tau}}},
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 = {We search for the rare leptonic decay B{sup +}{yields}{tau}{sup +}{nu}{sub {tau}} in a sample of 232x10{sup 6} BB pairs collected with the BABAR detector at the SLAC PEP-II B-Factory. Signal events are selected by examining the properties of the B meson recoiling against the semileptonic decay B{sup -}{yields}D*{sup 0}l{sup -}{nu}{sub l}. We find no evidence for a signal and set an upper limit on the branching fraction of B(B{sup +}{yields}{tau}{sup +}{nu}{sub {tau}})<2.8x10{sup -4} at the 90% confidence level. We combine this result with a previous, statistically independent BABAR search for B{sup +}{yields}{tau}{sup +}{nu}{sub {tau}} to give an upper limit of B(B{sup +}{yields}{tau}{sup +}{nu}{sub {tau}})<2.6x10{sup -4} at the 90% confidence level.},
doi = {10.1103/PhysRevD.73.057101},
journal = {Physical Review. D, Particles Fields},
number = 5,
volume = 73,
place = {United States},
year = {Wed Mar 01 00:00:00 EST 2006},
month = {Wed Mar 01 00:00:00 EST 2006}
}
  • The {tau}{sup -}{yields}{eta}{pi}{sup -}{pi}{sup +}{pi}{sup -}{nu}{sub {tau}} decay with the {eta}{yields}{gamma}{gamma} mode is studied using 384 fb{sup -1} of data collected by the BABAR detector. The branching fraction is measured to be (1.60{+-}0.05{+-}0.11)x10{sup -4}. It is found that {tau}{sup -}{yields}f{sub 1}(1285){pi}{sup -}{nu}{sub {tau}}{yields}{eta}{pi}{sup -}{pi}{sup +}{pi}{sup -}{nu}{sub {tau}} is the dominant decay mode with a branching fraction of (1.11{+-}0.06{+-}0.05)x10{sup -4}. The first error on the branching fractions is statistical and the second systematic. Note that no particle identification algorithm is applied to the charged tracks to distinguish pions from kaons. In addition, a 90% confidence level upper limit on the branchingmore » fraction of the {tau}{sup -}{yields}{eta}{sup '}(958){pi}{sup -}{nu}{sub {tau}} decay is measured to be 7.2x10{sup -6}. This last decay proceeds through a second-class current and is expected to be forbidden in the limit of isospin symmetry.« less
  • We present a search for the decay B{sup -}{yields}{tau}{sup -}{nu}{sub {tau}} in a sample of 88.9x10{sup 6} BB pairs recorded with the BABAR detector at the Stanford Linear Accelerator Center B factory. One of the two B mesons from the {upsilon}(4S) is reconstructed in a hadronic or a semileptonic final state, and the decay products of the other B in the event are analyzed for consistency with a B{sup -}{yields}{tau}{sup -}{nu}{sub {tau}} decay. We find no evidence of a signal and set an upper limit on the branching fraction of B(B{sup -}{yields}{tau}{sup -}{nu}{sub {tau}})<4.2x10{sup -4} at the 90% confidence level.
  • The recent observation of the purely leptonic decay B{sup {+-}}{yields}{tau}{sup {+-}}{nu}{sub {tau}} at the B factories permits a sizable contribution from a charged Higgs boson (H{sup {+-}}). Such a H{sup {+-}} would also contribute to the decays D{sub s}{sup {+-}}{yields}{mu}{sup {+-}}{nu}{sub {mu}} and D{sub s}{sup {+-}}{yields}{tau}{sup {+-}}{nu}{sub {tau}}, which are being measured with increasing precision at CLEO-c. We show that the branching ratios of D{sub s}{sup {+-}}{yields}{mu}{sup {+-}}{nu}{sub {mu}} and D{sub s}{sup {+-}}{yields}{tau}{sup {+-}}{nu}{sub {tau}} could be suppressed by up to 10% from the standard model prediction, which is larger than the anticipated precision in the measurements of these decaysmore » at forthcoming BES-III.« less
  • We present measurements of B{sup +{yields}}D*{sup 0{tau}+{nu}}{sub {tau}}and B{sup +{yields}}D{sup 0{tau}+{nu}}{sub {tau}}decays in a data sample of 657x10{sup 6} BB pairs collected with the Belle detector at the KEKB asymmetric-energy e{sup +}e{sup -} collider. We find 446{sub -56}{sup +58} B{sup +{yields}}D*{sup 0{tau}+{nu}}{sub {tau}}events with a significance of 8.1 standard deviations, and 146{sub -41}{sup +42} B{sup +{yields}}D{sup 0{tau}+{nu}}{sub {tau}}events with a significance of 3.5 standard deviations. The latter signal provides the first evidence for this decay mode. The measured branching fractions are B(B{sup +{yields}}D*{sup 0{tau}+{nu}}{sub {tau}})=(2.12{sub -0.27}{sup +0.28}(stat){+-}0.29(syst))% and B(B{sup +{yields}}D{sup 0{tau}+{nu}}{sub {tau}})=(0.77{+-}0.22(stat){+-}0.12(syst))%.
  • The purely leptonic decays of heavy mesons D{sub s}{yields}{tau}{nu}{sub {tau}} and B{yields}{tau}{nu}{sub {tau}} are studied in a sample of 1.5M Z{yields}qq-bar({gamma}) events collected in 1994 by the L3 detector at LEP. A signal for the decay chain D{sub s}{sup 0}{yields}{gamma}D{sub s}, D{sub s}{yields}{tau}{nu}{sub {tau}}, {tau}{yields}l{nu}{sub l}{nu}{sub {tau}} is observed in the invariant mass distribution M({gamma}D{sub s}). From this signal, a branching ration of B(D{sub s}{yields}{tau}{nu}{sub {tau}})=0.074{+-}0.028(stat){+-}0.016(syst){+-}0.018(norm) is derived, corresponding to a decay constant f{sub D{sub s}}=309{+-}58(stat){+-}33(syst){+-}38(norm) GeV. No signal is observed for the decay B{yields}{tau}{nu}{sub {tau}}, and an upper limit of B(B{yields}{tau}{nu}{sub {tau}})<5.7x10{sup -4} at 90% CL is set. Thesemore » results have been published in [1].« less