Download or read book Radiative Decays of the Upsilon 1S Meson written by Dave Z. Besson and published by . This book was released on 1986 with total page 274 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Search for Radiative Decays of Upsilon 1S Into Eta and Eta prime written by Vijay Singh Potlia and published by . This book was released on 2006 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: ABSTRACT: We conducted a new search for the radiative decay of Upsilon(1S) to the pseudoscalar mesons eta and eta-prime in (21.2"0.2) x 106 Upsilon(1S) decays collected with the CLEO III detector operation at the Cornell Electron Strorage Ring (CESR). The eta meson was reconstructed in the three modes eta to gamma gamma, eta to pipi−pi0 or eta to pi0 pi0 pi0. The eta-prime meson was reconstructed in the mode eta-prime to pi pi− eta with eta decaying through any of the above three modes; and also eta-prime to gamma rho0, where rho0 to pi+ pi−-. The first six of these decay chains were searched for in the previous CLEO II analysis on this subject, which used a data sample 14.6 times smaller. Five of the seven submodes were virtually background free. We found no signal events in four of them. The only exception was Upsilon(1S) to gamma eta-prime; eta to pi+ pi− pi0 where we observed two good signal candidates. The other two submodes (eta to gamma gamma and eta-prime to gamma rho) are background limited, and showed no excess of events in the signal region. We combined the results from different channels and obtained 90% confidence level (C.L.) upper limits branching fraction(Upsilon(1S) to gamma eta)

Download or read book Search for Exclusive Radiative Decays of upsilon 1S and upsilon 2S Mesons written by ARGUS Collaboration and published by . This book was released on 1988 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Search for Radiative upsilon 1S Decays Into Light Mesons written by Crystal Ball Collaboration and published by . This book was released on 1988 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Search for Invisible Decays of the Upsilon 1S written by and published by . This book was released on 2009 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: We search for invisible decays of the?(1S) meson using a sample of 91.4 x 106?(3S) mesons collected at the BABAR/PEP-II B Factory. We select events containing the decay?(3S) →??−?(1S) and search for evidence of an undetectable?(1S) decay recoiling against the dipion system. We set an upper limit on the branching fraction?(?(1S) → invisible)

Download or read book A Search for Narrow States in Radiative Upsilon Decays written by and published by . This book was released on 1986 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A search for new states produced in radiative UPSILON(1S) decays is accomplished by observing the inclusive photon energy spectrum. A narrow resonance in the energy spectrum indicates the existence of a new state X produced by the process UPSILON .-->. .gamma. X. The analysis is based on approximately 0.44 x 106 UPSILON(1S) events produced at the DORIS II ee− storage ring. These data were collected with the Crystal Ball detector between April 1983 and May 1986. This analysis finds no evidence for a new state, so upper limits on the branching ratio BR(UPSILON .-->. .gamma. X) are derived, assuming the state X decays primarily to high-multiplicity hadronic final states. In particular, if the state X were a minimal Higgs particle, its primary decay mode would be to the heaviest fermion-antifermion pair energetically available. For the radiative UPSILON(1S) decays studied here, the heavy fermions would be c anti c or s anti s quark states, over most of the relevant Higgs' mass range. The resulting upper limit for BR(UPSILON(1S) .-->. .gamma. X) is highly energy dependent but for X mass between 1.5 GeV and 8.0 GeV, the 90% confidence level upper limit is better than 8.0 x 10−4. For a Higgs' mass near 5.0 GeV, the upper limit is about 2.0 x 10−4 which is approximately equal to the lowest order calculation for the Wilczek mechanism. The Wilczek calculation with QCD radiative corrections predict branching ratios below the limits set here for all Higgs' masses.

Download or read book Search for Invisible Decays of the Upsilon 1S Meson at BABAR written by Lucas O. Winstrom and published by . This book was released on 2009 with total page 452 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Evidence for a Narrow Massive State in the Radiative Decays of the Upsilon written by and published by . This book was released on 1984 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Evidence is presented for a state, which we call zeta, with a mass M = (8322 +- 8 +- 24) MeV and a line width GAMMA 80 MeV (90% confidence level) obtained using the Crystal Ball (NaI(Tl) detector at DORIS II. Radiative transitions to this state are observed from about 100,000 UPSILON(1S) decays in two independent sets of data: one in which zeta .--. multiple hadrons, and one which is strongly biased towards zeta .-->. 2 low multiplicity jets. The branching ratio to this state from the UPSILON(1S) is of order 0.5%.

Download or read book Leptonic Decay of the Upsilon 1S Meson at Third Order in QCD written by and published by . This book was released on 2014 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Search for exclusive radiative decays of 1S and 2S mesons written by and published by . This book was released on 1988 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Evidence for the Eta b 1S in the Decay Upsilon 2S Gamma Eta b 1S written by and published by . This book was released on 2009 with total page 7 pages. Available in PDF, EPUB and Kindle. Book excerpt: We have performed a search for the [eta]{sub b}(1S) meson in the radiative decay of the [Upsilon](2S) resonance using a sample of 91.6 million [Upsilon](2S) events recorded with the BABAR detector at the PEP-II B factory at the SLAC National Accelerator Laboratory. We observe a peak in the photon energy spectrum at E{sub [gamma]} = 610.5{sub -4.3}{sup +4.5}(stat) ± 1.8(syst) MeV, corresponding to an [eta]{sub b}(1S) mass of 9392.9{sub -4.8}{sup +4.6}(stat) ± 1.9(syst) MeV/c2. The branching fraction for the decay [Upsilon](2S) → [gamma][eta]{sub b}(1S) is determined to be (4.2{sub -1.0}{sup +1.1}(stat) ± 0.9(syst)) x 10−4. The ratio [Beta]([Upsilon](2S) → [gamma][eta]{sub b}(1S))/[Beta]([Upsilon](3S) → {gamma}[eta]{sub b}(1S)) = 0.89{sub -0.23}{sup +0.25}(stat){sub -0.16}{sup +0.12}(syst) is consistent with the ratio expected for magnetic dipole transitions to the [eta]{sub b}(1S) meson.

Download or read book Search for exclusive radiative decays of t63 1S and t63 2S mesons written by and published by . This book was released on 1988 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book High Energy Physics Index written by and published by . This book was released on 1990 with total page 716 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Search for Primarily Non interacting Decay Modes of the Upsilon written by and published by . This book was released on 1986 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The hadronic transition UPSILON(2S) .-->. .pi.°.pi.°UPSILON(1S) is utilized to search for the reactions: UPSILON(1S) .-->. non-interacting particles and UPSILON(1S) .-->. .gamma. + non-interacting particles. 44 pb−1 of UPSILON(2S) data were taken by the Crystal Ball detector at the DORIS II storage ring in order to perform this study. An upper limit of BR(UPSILON .-->. Unseen) 12% (90% C.L.), is obtained via this approach. The second process investigated involved the radiative decay of the Upsilon into non-interacting particles. 57 pb−1 of UPSILON(2S) data was available for this study. An upper limit on the branching ratio BR(UPSILON .--. .gamma. + Unseen) is measured for photon energies in the range 500 MeV E.gamma.

Download or read book A Search for Narrow States in Radiative Upsilon Decays written by Stephen T. Lowe and published by . This book was released on 1986 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Radiative Decays of the Upsilon 2S Resonance written by and published by . This book was released on 1984 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Crystal Ball Detector at DORIS II was used to study radiative decays of the upsilon (2S) resonance with more than twice the previously available data. The inclusive photon spectrum of hadronic upsilon (2S) decays and the exclusive channel upsilon (2S) .-->. .gamma gamma. upsilon (1S) .-->. .gamma gamma. ll− were analyzed. In the inclusive spectrum three significant photon lines at energies of E.gamma.1 = (108.2 +- 0.7 +- 4) MeV, E.gamma.1 = (127.1 +- 0.8 +- 4) MeV and E.gamma.3 = (160.0 +- 2.4 +- 4) MeV with branching fractions of (6.0 +- 0.7 +- 0.9)%, (6.6 +- 0.8 +- 1.0)%, (2.6 +- 0.7 +- 0.8)% respectively were measured. The lines are consistent with being transitions from the upsilon (2S) to the 3P2, 3P1 and 3P0 states. In addition a line at E.gamma. approx. 427 MeV was observed which is interpreted as transitions from the 3P2 1 states to the upsilon (1S). 17 references.

Download or read book Study of Radiative Upsilon Decays written by Ilya Korolkov and published by . This book was released on 1999 with total page 204 pages. Available in PDF, EPUB and Kindle. Book excerpt: