Electronic branching ratio of the tau lepton Ammar, R; Baringer, P; Coppage, D ...
Physical review. D, Particles and fields,
1992-Jun-01, 1992-6-00, 19920601, 1992-06-01, Letnik:
45, Številka:
11
Journal Article
Odprti dostop
Using data accumulated by the CLEO I detector operating at the Cornell Electron Storage Ring, we have measured the ratio {ital R}={Gamma}({tau}{r arrow}{ital e}{bar {nu}}{sub {ital e}}{nu}{sub ...{tau}})/{Gamma}{sub 1}, where {Gamma}{sub 1} is the {tau} decay rate to final states with one charged particle. We find {ital R}=0.2231{plus minus}0.0044{plus minus}0.0073 where the first error is statistical and the second is systematic. Together with the measured topological one-charged-particle branching fraction, this yields the branching fraction of the {tau} lepton to electrons, {ital B}{sub {ital e}}=0.192{plus minus}0.004{plus minus}0.006.
Radiative Upsilon (1S) decays Fulton, R; Hempstead, M; Jensen, T ...
Physical review. D, Particles and fields,
1990-Mar-01, 1990-3-00, 19900301, 1990-03-01, Letnik:
41, Številka:
5
Journal Article
Odprti dostop
We report on a study of exclusive radiative decays of the {Upsilon}(1{ital S}) resonance. We have considered decays into final states of the form {Upsilon}{r arrow}{gamma}{ital n}({ital h}{sup ...+}{ital h}{sup {minus}}), with ({ital h}{sup +}{ital h}{sup {minus}}) denoting a charged-hadron pair (either {pi}{sup +}{pi}{sup {minus}},{ital K}{sup +}{ital K}{sup {minus}}, or {ital p{bar p}}), and {ital n} denoting the number of such pairs in the event. We measure branching ratios for {ital n}=2, 3, and 4, and search for structure in the recoiling hadronic system. For the {ital n}=1 case, we present upper limits. No evidence is observed for two-body radiative decays of the {Upsilon}(1{ital S}) meson in any of the above channels.
Exclusive decays and masses of the B mesons Bebek, C; Berkelman, K; Blucher, E ...
Physical review. D, Particles and fields,
09/1987, Letnik:
36, Številka:
5
Journal Article
Limit on the Tau neutrino mass CINABRO, D; HENDERSON, S; BARINGER, P ...
Physical review letters,
06/1993, Letnik:
70, Številka:
24
Journal Article
Recenzirano
Odprti dostop
A limit on the tau neutrino mass ital Msub nutau is obtained from a study of tau decays in the reaction ital esup +ital eminusr arrowtausup +tausup minus at center-of-mass energies similar to10.6 ...GeV. The result is based on an end-point analysis of the invariant mass spectrum of the decay products in the decay modes tausup minusr arrow3ital hsup minus2ital hsup +nusub tau and tausup minusr arrow2ital hsup minusital h+2pisup 0nusub tau. The data sample used in this analysis contains 1.77times10sup 6 tau pairs, corresponding to an integrated luminosity of 1.92 fbsup minus1, and is substantially larger than previous data samples used to place a limit on ital Msub nutau. The limit obtained for both five-hadron modes together is 32.6 MeV at 95% C.L.
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