Measurement of the branching fraction of the radiative decay τ− → μ−νμντγ

doi:10.1016/S0370-2693(96)01284-1

Physics Letters B

Volume 388, Issue 2, 14 November 1996, Pages 437-449

https://doi.org/10.1016/S0370-2693(96)01284-1 Get rights and content

Abstract

The branching ratio of the radiative τ decay $τ^{−} → μ^{−} ν_{μ} ν_{τ} γ$ has been measured using data collected with the OPAL detector at LEP. The result is $B(τ^{−} → μ^{−} ν_{μ} ν_{τ} γ) = (3.0 ± 0.4 ± 0.5) × 10^{−3}$ for photon energies above 20 MeV measured in the τ rest frame. The result is in good agreement with the Standard Model expectation.

References (17)

R Akers
Z. Phys. C
(1995)
C Fronsdal et al.
Phys. Rev.
(1959)
R.E Behrends et al.
Phys. Rev.
(1956)
S Jadach et al.
Comp. Phys. Comm.
(1993)
D.Y Wu
Phys. Rev. D
(1990)
K Ahmet
Nucl. Inst. Meth. A
(1991)
P.P Allport
Nucl. Inst. Meth. A
(1993)
P.P Allport
Nucl. Inst. Meth. A
(1994)
M.Z Akrawy
Phys. Lett. B
(1990)
J Allison
Nucl. Inst. Meth, A
(1992)
R Brun
GEANT3 Users Guide
(1989)
R Akers
Z. Phys. C
(1994)

There are more references available in the full text version of this article.

Cited by (9)

Measurement of the branching fractions of radiative leptonic τ decays τ→lγνν-, (l=e, μ) at BaBar
2015, Nuclear and Particle Physics Proceedings
We perform a measurement of the branching fractions for $τ \to l γ ν \bar{ν}$ , ( $l = e, μ$ ) decays for a minimum photon energy of 10 MeV in the τ rest frame using $430 {fb}^{- 1}$ of $e^{+} e^{-}$ collisions collected at the center-of-mass energy of the $ϒ (4 S)$ resonance with the BaBar detector at the PEP-II storage rings. We find $B (τ \to μ γ ν ν) = (3.69 \pm 0.03 \pm 0.10) \times 10^{- 3}$ and $B (τ \to e γ ν ν) = (1.847 \pm 0.015 \pm 0.052) \times 10^{- 2}$ where the first quoted error is statistical and the second is systematic. These results represent a substantial improvement with respect to existing measurements for both channels.
A measurement of the τ- → μ-ν<inf>μ</inf>ν<inf>τ</inf> branching ratio
2003, Nuclear Physics B - Proceedings Supplements
The $ρ^{−} → μ^{−} ν_{μ} ν_{τ}$ branching ratio has been measured using data collected from 1990 to 1995 by the OPAL detector at the LEP collider. The resulting value of B( $τ^{−} → μ^{−} τ_{μ} τ_{τ}) = 0.1734 ± 0.0009(stat) ± 0.0005(syst)$ has been used in conjunction with other OPAL measurements to test lepton universality, yielding the coupling constant ratios g_μ/g_e = 1.0005±0.0043 and g_τ/g_e = 1.0031 ± 0.0047, in good agreement with the standard Model prediction of unity, and also to determine a value for the Michel parameter η = 0.004± 0.036. This is subsequently used to find a model-dependent limit of the mass for the charged Higgs boson, m_H^± > 1.30 tan β, in the Minimal Supersymmetric Standard Model framework.
A measurement of the τ- → μ-v̄<inf>μ</inf>v<inf>τ</inf> branching ratio
2003, Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics
The $τ^{−} →μ^{−} ν ̄_{μ} ν_{τ}$ branching ratio has been measured using data collected from 1990 to 1995 by the OPAL detector at the LEP collider. The resulting value of has been used in conjunction with other OPAL measurements to test lepton universality, yielding the coupling constant ratios g_μ/g_e=1.0005±0.0044 and g_τ/g_e=1.0031±0.0048, in good agreement with the Standard Model prediction of unity. A value for the Michel parameter η=0.004±0.037 has also been determined and used to find a limit for the mass of the charged Higgs boson, m_H^±>1.28tanβ, in the Minimal Supersymmetric Standard Model.
Radiative leptonic tau decays and a search for τ- → μ-γ
2001, Nuclear Physics B - Proceedings Supplements
Using the CLEO II detector at the Cornell Electron Storage Ring (CESR) the radiative decay of the τ has been studied and a search for the lepton number violating decay τ⁻ → μ⁻γ has been performed. For a 10 MeV minimum photon energy in the τ rest frame $B$ (τ⁻ → ν_τμ⁻ $ν$ _μγ) = (3.61 ± 0.16 ± 0.35 × 10⁻³) and $B$ (τ⁻ → ν_τe⁻ $ν$ _eγ) = (1.75 ± 0.06 ± 0.17 × 10⁻²), in agreement with the Standard Model. For the decay τ⁻ → μ⁻γ an upper limit of $B$ )τ⁻ → μ⁻γ) <- 1.1 × 10⁻⁶ @ 90% CL was obtained.
A Perspective on Tau Physics *‡
1999, Nuclear Physics B - Proceedings Supplements
Measurement of the branching fractions of the radiative leptonic τ decays τ →eγν ν ¯ and τ →μγν ν ¯ at BABAR measurement of the branching fractions of the ... J.P. Lees et al.
2015, Physical Review D - Particles, Fields, Gravitation and Cosmology

View all citing articles on Scopus

¹: And at TRIUMF, Vancouver, Canada V6T 2A3.

²: And Royal Society University Research Fellow.

³: And Institute of Nuclear Research, Debrecen, Hungary.

⁴: And Department of Experimental Physics, Lajos Kossuth University, Debrecen, Hungary.

View full text

Article preview

Physics Letters B

Abstract

References (17)

Z. Phys. C

Phys. Rev.

Phys. Rev.

Comp. Phys. Comm.

Phys. Rev. D

Nucl. Inst. Meth. A

Nucl. Inst. Meth. A

Nucl. Inst. Meth. A

Phys. Lett. B

Nucl. Inst. Meth, A

GEANT3 Users Guide

Z. Phys. C

Cited by (9)

Measurement of the branching fractions of radiative leptonic τ decays τ→lγνν-, (l=e, μ) at BaBar

A measurement of the τ<sup>-</sup> → μ<sup>-</sup>ν<inf>μ</inf>ν<inf>τ</inf> branching ratio

A measurement of the τ<sup>-</sup> → μ<sup>-</sup>v̄<inf>μ</inf>v<inf>τ</inf> branching ratio

Radiative leptonic tau decays and a search for τ<sup>-</sup> → μ<sup>-</sup>γ

A Perspective on Tau Physics *‡

Measurement of the branching fractions of the radiative leptonic τ decays τ →eγν ν ¯ and τ →μγν ν ¯ at BABAR measurement of the branching fractions of the ... J.P. Lees et al.