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1. Analysis of the 33-133-133-1final state in photon-photon collisions

Author

S. Lowe, M. Reidenbach, D. Besset, D. Antreasyan, A. M. Cartacci, G. Glaser, A. C. König, R. Cowan, Grzegorz Nowak, C. W. Peck, F. H. Heinsius, B. Lurz, H. W. Bartels, P. McBride, B. Renger, G. Conforto, U. Volland, G.L. Godfrey, P. Ratoff, H. Marsiske, K. Wachs, R. T. Van de Walle, G. Landi, K. Wacker, P. Schmitt, J. Irion, W. Lockman, H. Meyer, W. Koch, D. Gelphman, J. Schütte, H. J. Trost, S. Krüger, K. Graaf, T. Kiel, C. Rippich, S. Leffler, P. G. Pelfer, Elliott D. Bloom, V. Stock, H. Wegener, Andrea Bizzeti, F. Messing, D. Sievers, B. Pollock, D. A. Williams, J. Gaiser, M. Cavalli-Sforza, M. Kobel, Hans J. Vogel, H. Janssen, A. M. Litke, R. Cabenda, A. Engler, B. Monteleoni, Z. Jakubowski, R. Hofstadter, H. Kilian, A. Schwarz, R. W. Kraemer, S. Keh, B. Niczyporul, B. Muryn, A. Voigt, T. Koiber, K. Fairfield, W. Maschmann, S. Cooper, I. Kirkbride, D. Marlow, R. Clare, Tomasz Skwarnicki, F. C. Porter, F. H. Heimlich, D. Prindle, K. Brockmüller, A. Fridman, B. van Uitert, J. Tompkins, U. Strohbusch, J. Schotanus, A. Compagnucci, Ch Bieler, K. Strauch, I. C. Brock, R. Lekebusch, G. Folger, W. J. Metzger, S. Lee, K. Königsmann, D. G. Coyne, K. Karch, R. Nernst, W. Walk, P. Zschorsch, T. Lesiak, J. K. Bienlein, and M. Scheer

Subjects
Nuclear physics, Physics, Photon, Physics and Astronomy (miscellaneous), Meson, Mass distribution, Dalitz plot, Resonance, DESY, Invariant mass, Atomic physics, Engineering (miscellaneous), Crystal Ball
Abstract

The reactione + e - →e + e - ηπ0π0→e + e - 6γ has been analysed using the full data sample taken with the Crystal Ball detector at the DORIS II storage ring at DESY. The ηπ0π0 invariant mass spectrum is dominated by the η', for which we determine the radiative width Γγγ(η') to be (4.5±0.3±0.5)keV. Near 1.9 GeV/c2 we observe a second enhancement in the ηπ0π0 mass distribution. Assuming that these events are created by the production and subsequent decay of a wide resonanceX(1900), we have investigated the decay modes, the invariant mass distributions of the ηπ0 and π0π0 subsystems and the angular distributions of the final state mesons. We find that the data is best described byJ PC=2∓. For thisJ P assignment the resonance parameters are Γγγ(X) BR(X→ηππ)=(0.95±0.27±0.20) keV Γtot (X)=(221±92±44)MeV, andM(X)=(1881±32±40) MeV/c2.

Published
1992
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2. Measurement of the branching ratios for the decays τ→hadron π0ν and τ→hadron π0π0ν

Author

M. Cavalli-Sforza, G. Landi, H. Meyer, H. J. Trost, D. Besset, A. M. Cartacci, G. Glaser, A. C. König, F. H. Heinsius, B. Renger, J. Irion, W. Lockman, R. W. Krämer, M. Reidenbach, I. Kirkbride, F. H. Heimlich, H. Janssen, B. Niczyporuk, D. Antreasyan, S. Leffler, P. G. Pelfer, H. Wegener, H. Marsiske, K. Brockmüller, D. Sievers, W. Walk, F. C. Porter, B. Pollock, R. Cowan, A. Fridman, B. van Uitert, D.G. Coyne, Z. Jakubowski, R. Hofstadter, J. Gaiser, M. Scheer, Tomasz Skwarnicki, G.L. Godfrey, Grzegorz Nowak, A. Engler, H. Kilian, C. Rippich, B. Monteleoni, D. Gelphman, S. Cooper, R. Cabenda, U. Volland, G. Conforto, W. Koch, J. Schütte, K. Graaf, R. T. Van de Walle, K. Königsmann, K. Wacker, J. Schotanus, K. Wachs, P. Schmitt, P. Zschorsch, A. Compagnucci, B. Lurz, P. Ratoff, K. Strauch, Elliott D. Bloom, R. Nernst, B. Muryn, S. Keh, K. Fairfield, A. Voigt, R. Lekebusch, W. Maschmann, S. Lowe, P. McBride, G. Folger, R. Clare, U. Strohbusch, D. Prindle, Ch Bieler, Hans J. Vogel, H. W. Bartels, M. Kobel, A. M. Litke, F. Messing, T. Kloiber, S. Krüger, A. Schwarz, V. Stock, T. Kiel, Andrea Bizzeti, K. Karch, C. Peck, D. A. Williams, J. Tompkins, J. K. Bienlein, R. Lee, D. Marlow, W. J. Metzger, and I. C. Brock

Subjects
Semileptonic decay, Physics, Nuclear physics, Nuclear and High Energy Physics, Particle decay, Pion, Meson, Branching fraction, Hadron, Atomic physics, Crystal Ball, Lepton
Abstract

The Crystal Ball detector at the DORIS II storage ring at DESY has been used to measure the branching ratios for the decay modes τ ± →h ± π 0 ν and τ ± →h ± π 0 π 0 ν , where h ± is any charged hadron. The results are BR( τ ± → h ± π 0 ν ) = (22.0±0.8±1.9)%, BR( τ ± → h ± π 0 π 0 ν ) = (5.7±0.5 +1.0 −1.7 )%. The first result is in good agreement with the present world average. The decay mode h ± π 0 π 0 ν is reconstructed in τ decays for the first time. Its branching ratio, however, is somewhat lower than the corresponding world average, and therefore tends to increase the one-prong problem.

Published
1991
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3. First observation of the reactionγγ→π 2→π 0 π 0 π 0

Author

I. Brock, C. h. Bieler, D. Besset, H. W. Bartels, Andrea Bizzeti, R. Cabenda, E. D. Bloom, K. Brockmüller, J. K. Bienlein, and D. Antreasyan

Subjects
Nuclear physics, Physics, Partial width, Physics and Astronomy (miscellaneous), Pi, Resonance, Invariant mass, DESY, Engineering (miscellaneous), Crystal Ball, Storage ring, Gamma gamma
Abstract

The Crystal Ball detector has been used at the DORIS II storage ring at DESY to study the reactionγγ→π0π0π0 in theπ0π0π0 invariant mass range from 850 MeV/c2 to 2600 MeV/c2. An enhancement around 1750 MeV/c2 is attributed to theπ2(1670) resonance. The observedπ0π0 invariant mass distribution and theπ0 angular distributions are consistent with those expected for the decay chainπ2→π0f2(1270)→π0π0π0. From our measurements we find the following resonance parameters: two photon partial width\(\Gamma _{\pi _2 }^{\gamma \gamma }= (1.41 \pm 0.23 \pm 0.28)keV\), massM(π2)=(1742±31±49)MeV/c2. and total width\(\Gamma _{\pi _2 }^{tot}= (236 \pm 49 \pm 36)MeV\).

Published
1990
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4. Observation of the exclusive decayB→evD * and search forB→evπ 0

Author

J. Tompkins, K. Königsmann, M. Scheer, H. Meyer, K. Wacker, P. Schmitt, Elliott D. Bloom, B. Lurz, Z. Jakubowski, W. Koch, B. Niczyporuk, D. Sievers, H. Janssen, M. Reidenbach, W. Walk, S. Lowe, A. M. Cartacci, G. Glaser, A. C. König, F. H. Heinsius, S. Keh, K. Fairfield, W. Maschmann, S. Cooper, J. Schotanus, S. Leffler, P. G. Pelfer, H. W. Bartels, J. Schütte, A. Compagnucci, H. Wegener, R. Clare, K. Strauch, T. Lesiak, B. Monteleoni, J. K. Bienlein, D. Gelphman, S. Krüger, K. Karch, T. Kiel, B. Muryn, R. Lekebusch, G. Folger, W. J. Metzger, D. A. Williams, H. Kilian, Tomasz Skwarnicki, F. C. Porter, Ch Bieler, V. Stock, Andrea Bizzeti, G. Landi, A. M. Litke, J. Irion, K. Graaf, M. Kobel, A. Schwarz, D. Antreasyan, P. McBride, A. Voigt, C. W. Peck, G. Conforto, D. G. Coyne, U. Strohbusch, H. Marsiske, I. Kirkbride, R. Hofstadter, F. H. Heimlich, Grzegorz Nowak, U. Volland, K. Brockmüller, K. Wachs, A. Fridman, B. van Uitert, G.L. Godfrey, R. T. Van de Walle, and M. Cavalli-Sforza

Subjects
Physics, Nuclear physics, Particle physics, Physics and Astronomy (miscellaneous), Meson, Branching fraction, Engineering (miscellaneous), Storage ring, Crystal Ball
Abstract

The Crystal Ball detector at thee+e− storage ring DORIS II has been used to analyze exclusive semileptonic decays ofB mesons produced at γ(4S) energies. The decayB→evD* has been observed with a branching ratio of (7.0±1.8±1.4)% using theπ°D decay mode of theD*. In addition we have searched for the exclusive semileptonic decayB±→e±vπ0. We find an upper limit onB±→e±vπ0 of 0.22% at the 90% CL.

Published
1990
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5. Limits on axion and light Higgs boson production in ϒ (1S) decays

Author

P. Zschorsch, J. Schotanus, A. Compagnucci, B. Niczyporuk, K. Strauch, A. Voigt, R. Lekebusch, H. Janssen, S. Leffler, K. Karch, P. G. Pelfer, D. Gelphman, H. Wegener, D. G. Coyne, S. Cooper, I. Kirkbride, U. Strohbusch, S. Lowe, G. Folger, F. H. Heimlich, K. Brockmüller, R. Nernst, K. Königsmann, M. Reidenbach, A. Fridman, B. van Uitert, V. Stock, H. Marsiske, H. W. Bartels, Andrea Bizzeti, K. Wacker, B. Muryn, M. Kobel, P. Schmitt, P. Ratoff, D. Prindle, Tomasz Skwarnicki, Elliott D. Bloom, A. Schwarz, M. Cavalli-Sforza, D. Besset, A. M. Cartacci, G. Glaser, A. C. König, J. Tompkins, F. H. Heinsius, D. Gaiser, A. M. Litke, B. Lurz, J. Irion, W. Lockman, R. W. Krämer, W. Koch, H. Vogel, P. McBride, T. Kloiber, A. Engler, B. Renger, D. Sievers, F. C. Porter, H. Meyer, K. Graaf, H. J. Trost, I. Brock, C. Rippich, B. Pollock, D. Antreasyan, R. Hofstadter, Grzegorz Nowak, H. Kilian, G.L. Godfrey, R. Cabenda, U. Volland, G. Conforto, R. T. Van de Walle, D. Marlow, B. Monteleoni, K. Wachs, W. Walk, R. Cowan, J. Schütte, M. Scheer, G. Landi, S. Krüger, T. Kiel, D. A. Williams, F. Messing, S. Keh, K. Fairfield, W. Maschmann, R. Clare, Z. Jakubowski, C. Peck, J. K. Bienlein, Ch Bieler, R. Lee, and W. J. Metzger

Subjects
Quantum chromodynamics, Physics, Nuclear and High Energy Physics, Particle physics, Physics::Instrumentation and Detectors, Electron–positron annihilation, High Energy Physics::Phenomenology, Standard Model, Nuclear physics, High Energy Physics::Theory, Higgs boson, High Energy Physics::Experiment, Production (computer science), Limit (mathematics), Axion, Crystal Ball
Abstract

We have searched for axion and light Higgs boson production in the channel ϒ (1 S ) → (a 0 or h 0 ) + γ , where the non-interacting axion a 0 and the Higgs boson h 0 do not decay in the detector. We find no evidence for an axion and give an upper limit, Br( ϒ (1S) → a 0 γ ) −5 (90% CL), for long-lived axions. Combining our limit with the previous search in J / ψ decays, we are able to rule out the axion in the standard model with first order QCD corrections. Our ϒ (1S) data also rule out a Higgs boson with mass m h

Published
1990
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6. Measurement ofπ0π0production in two-photon collisions

Author

M. Reidenbach, M. Cavalli-Sforza, Z. Jakubowski, H. Meyer, H. J. Trost, Grzegorz Nowak, D. Sievers, W. Koch, K. Wacker, U. Volland, S. Leffler, P. G. Pelfer, Ch Bieler, D. Besset, A. M. Cartacci, G. Glaser, A. C. König, H. Wegener, A. Engler, P. Schmitt, J. Schotanus, A. Compagnucci, K. Strauch, K. Wachs, H. Kilian, Elliott D. Bloom, F. H. Heinsius, B. Monteleoni, D. Antreasyan, I. Kirkbride, B. Renger, S. Lowe, R. Lekebusch, M. Scheer, F. H. Heimlich, R. Cowan, K. Brockmüller, C. W. Peck, H. Janssen, A. M. Litke, C. Rippich, P. Ratoff, A. Voigt, G. Conforto, K. Graaf, G.L. Godfrey, B. van Uitert, S. Cooper, J. Irion, W. Lockman, R. T. Van de Walle, D. G. Coyne, Tomasz Skwarnicki, H. W. Bartels, D. Prindle, S. Keh, K. Fairfield, V. Stock, F. Messing, H. Marsiske, W. Maschmann, T. Kloiber, R. Hofstadter, R. Clare, Andrea Bizzeti, K. Karch, Hans J. Vogel, A. Fridman, S. Krüger, T. Kiel, J. K. Bienlein, R. Lee, B. Pollock, U. Strohbusch, D. A. Williams, D. Gelphman, R. Nernst, J. Tompkins, D. Marlow, D. Gaiser, W. J. Metzger, B. Muryn, I. C. Brock, J. Schütte, B. Lurz, B. Niczyporuk, P. Zschorsch, W. Walk, P. McBride, M. Kobel, A. Schwarz, G. Folger, K. Königsmann, G. Landi, F. C. Porter, R. Cabenda, and R. W. Kraemer

Subjects
Physics, Particle physics, Pi, Resonance, Production (computer science), Atomic physics, Helicity, Crystal Ball, Spin-½
Abstract

The reaction ${e}^{+}{e}^{\ensuremath{-}}\ensuremath{\rightarrow}{e}^{+}{e}^{\ensuremath{-}}{\ensuremath{\pi}}^{0}{\ensuremath{\pi}}^{0}$ has been analyzed using 97 ${\mathrm{pb}}^{\ensuremath{-}1}$ of data taken with the Crystal Ball detector at the DESY ${e}^{\ensuremath{-}}{e}^{+}$ storage ring DORIS II at beam energies around 5.3 GeV. For the first time we have measured the cross section for $\ensuremath{\gamma}\ensuremath{\gamma}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{0}{\ensuremath{\pi}}^{0}$ for ${\ensuremath{\pi}}^{0}{\ensuremath{\pi}}^{0}$ mvariant masses ranging from threshold to about 2 GeV. We measure an approximately flat cross section of about 10 nb for $W={m}_{{\ensuremath{\pi}}^{0}{\ensuremath{\pi}}^{0}}l0.8$ GeV, which is below 0.6 GeV, in good agreement with a theoretical prediction based on an unitarized Born-term model. At higher invariant masses we observe formation of the ${f}_{2}(1270)$ resonance and a hint of the ${f}_{0}(975)$. We deduce the following two-photon widths: ${\ensuremath{\Gamma}}_{\ensuremath{\gamma}\ensuremath{\gamma}}({f}_{2}(1270))=3.19\ifmmode\pm\else\textpm\fi{}{0.16\ifmmode\pm\else\textpm\fi{}}_{0.28}^{0.29}$ keV and ${\ensuremath{\Gamma}}_{\ensuremath{\gamma}\ensuremath{\gamma}}({f}_{0}(975))l0.53$ keV at 90% C.L. The decay-angular distributions show the ${\ensuremath{\pi}}^{0}{\ensuremath{\pi}}^{0}$ system to be dominantly spin 0 for $Wl0.7$ GeV and spin 2, helicity 2 in the ${f}_{2}(1270)$ region, with helicity 0 contributing at most 22% (90% C.L.).

Published
1990
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7. FE- Modeling of the Three-Dimensional Stress Field in a Plasticising Short Fibre Reinforced Composite

Author

K. Friedrich and K. Brockmüller

Subjects
Stress (mechanics), chemistry.chemical_classification, Nonlinear system, Materials science, Field (physics), chemistry, Composite number, Polymer, Composite material, Deformation (engineering), Three dimensional stress, Finite element method
Abstract

A three-dimensional finite element (FE) model for the deformation behaviour of a short fibre reinforced polymer is presented. This model applies to composites with strong fibre alignment. Stress distributions are calculated for quasi elastic and materially nonlinear behaviour. These lead to assumptions about the failure mechanisms in such composites which compare well with experimental observations of other authors.

Published
1992
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8. Measurement of the direct photon spectrum from Υ(1S) decays

Author

G. Landi, A. Voigt, M. Reidenbach, B. Monteleoni, U. Volland, G. Folger, Z. Jakubowski, K. Wachs, A. M. Cartacci, G. Glaser, A. C. König, D. Antreasyan, F. H. Heinsius, J. Schotanus, A. Compagnucci, D. A. Williams, K. Strauch, S. Keh, K. Fairfield, W. Maschmann, R. Lekebusch, G. Conforto, D. Coyne, W. Koch, S. Lowe, K. Graaf, G. Nowak, R. Hofstadter, P. G. Pelfer, H. Wegener, S. Krüger, T. Kiel, H. Killian, P. McBride, B. Niczyporuk, B. Muryn, Ch Bieler, M. Kobel, J. Schütte, M. Scheer, D. Sievers, B. Lurz, Tomasz Skwarnicki, J. Irion, H. Marsiske, P. Schmitt, Elliott D. Bloom, H. Janssen, S. Cooper, R. T. Van de Walle, K. Königsmann, J. K. Bienlein, W. J. Metzger, V. Stock, Andrea Bizzeti, K. Karch, J. Tompkins, I. C. Brock, M. Cavalli-Sforza, G. Godfrey, I. Kirkbride, F. H. Heimlich, K. Brockmüller, A. Fridman, B. van Uitert, and U. Strohbusch

Subjects
Physics, Nuclear and High Energy Physics, Annihilation, Photon, Meson, radiative decay, Upsilon(1S), Crystal Ball, Elementary particle, Quarkonium, Spectral line, Gluon, Nuclear physics, Massless particle
Published
1991

9. Inclusive J/Psi production in decays of B mesons

Author

S. Leffler, P. G. Pelfer, H. Wegener, Grzegorz Nowak, D. Antreasyan, R. Nernst, U. Volland, I. Kirkbride, F. H. Heimlich, K. Brockmüller, A. Fridman, B. van Uitert, K. Wachs, D. Besset, F. Messing, T. Kloiber, W. Walk, C. W. Peck, H. Meyer, H. Janssen, A. M. Cartacci, G. Glaser, A. C. König, S. Lowe, A. M. Litke, M. Kobel, H. J. Trost, F. H. Heinsius, J. Schütte, B. Renger, M. Scheer, H. W. Bartels, D. Sievers, J. Tompkins, Z. Jakubowski, B. Niczyporuk, U. Strohbusch, B. Lurz, D. Gelphman, W. Koch, A. Schwarz, R. Hofstadter, I. C. Brock, K. Graaf, K. Wacker, J. Schotanus, A. Compagnucci, B. Pollock, P. Schmitt, C. Rippich, K. Strauch, A. Voigt, S. Cooper, R. Lekebusch, Elliott D. Bloom, B. Monteleoni, G. Folger, P. McBride, P. Zschorsch, K. Königsmann, G. Conforto, V. Stock, Andrea Bizzeti, S. Keh, F. C. Porter, K. Fairfield, W. Maschmann, D. G. Coyne, D. Prindle, H. Marsiske, Tomasz Skwarnicki, R. Clare, B. Muryn, R. Cowan, K. Karch, S. Krüger, R. Cabenda, Hans J. Vogel, T. Kiel, G.L. Godfrey, R. W. Kraemer, R. T. Van de Walle, J. Gaiser, D. A. Williams, G. Landi, J. K. Bienlein, Ch Bieler, R. Lee, D. Marlow, W. J. Metzger, M. Reidenbach, P. Ratoff, M. Cavalli-Sforza, J. Irion, W. Lockman, A. Engler, and H. Kilian

Subjects
Physics, Particle physics, Physics and Astronomy (miscellaneous), Meson, Branching fraction, Hadron, B mesons, Quarkonium, J/Psi, Nuclear physics, Particle decay, Pair production, decays, Crystal Ball, High Energy Physics::Experiment, B meson, Engineering (miscellaneous)
Abstract

The production ofJ/ψ inB meson decays has been measured on the Γ(4S) resonance using the Crystal Ball detector at thee+e− storage ring DORIS II. TheJ/ψ is identified by itse+e− decay mode. We obtain a branching ratio of BR(B→J/ψX)=(1.12±0.33±0.25)% in good agreement with theoretical predictions based on color suppression. TheJ/ψ momentum distribution is observed to be peaked at high values. This implies a substantial contribution from directB meson decays to theJ/ψ. In addition upper limits onJ/ψ production in Γ(1S) and Γ(2S) decays and in continuum processes are determined.

Published
1990

10. Measurement of the properties of theη’and search for other resonances in γγ→ηπ0π0

Author

A. Fridman, F. H. Heimlich, H. Meyer, H. J. Trost, J. Schotanus, Hans J. Vogel, D. Antreasyan, W. Walk, Ch Bieler, P. McBride, G. Landi, C. W. Peck, G. Drews, K. Strauch, G. Conforto, S. Cooper, D. C. Coyne, Daniel Robert Marlow, W. J. Metzger, Tomasz Skwarnicki, R. Lekebusch, Z. Jakubowski, S. Leffler, Raymond Lee, M. Scheer, J. Gaiser, H. Marsiske, P. G. Pelfer, H. Wegener, B. Monteleoni, R. Nernst, W. Koch, Matteo Cavalli-Sforza, K. Karch, R. Cowan, T. Matsui, C. Rippich, D. Sievers, K. Wacker, P. Schmitt, S. Lowe, F. C. Porter, Alan Litke, F. Selonke, Elliott D. Bloom, C. A. Edwards, G.L. Godfrey, G. Folger, J. Tompkins, J. K. Bienlein, W. S. Lockman, P. Zschorsch, K. Königsmann, H. W. Bartels, R. T. Van de Walle, R. Cabenda, P. N. Ratoff, A. Voigt, Robert Clare, David R. Williams, R. W. Kraemer, B. Niczyporuk, I. C. Brock, D. Gelphman, U. Strohbusch, F. Messing, S. Krüger, D. Prindle, T. Kloiber, V. Stock, Andrea Bizzeti, A. Schwarz, A. Engler, S. Keh, K. Fairfield, H. Kilian, W. Maschmann, I. Kirkbride, J. Irion, B. Pollock, K. Brockmüller, R. Hofstadter, D. Besset, A. M. Cartacci, G. Glaser, A. C. König, Grzegorz Nowak, B. Renger, U. Volland, K. Wachs, B. Lurz, and M. Kobel

Subjects
Physics, Pion, Meson, Astrophysics::High Energy Astrophysical Phenomena, Hadron, Mass spectrum, Analytical chemistry, Pi, High Energy Physics::Experiment, Elementary particle, Crystal Ball, Spectral line
Abstract

The reaction e/sup +/e/sup -/..-->..e/sup +/e/sup -/eta..pi../sup 0/..pi../sup 0/ has been observed with the Crystal Ball detector at the DORIS II storage ring at DESY. The eta..pi../sup 0/..pi../sup 0/ mass spectrum is dominated by the eta', and the two-photon width GAMMA/sub eta//sub '//sub ..-->..//sub ..gamma..//sub ..gamma../ is determined to be 4.6 +- 0.4 +- 0.6 keV. Limits on GAMMA/sub X//sub ..-->..//sub ..gamma..//sub ..gamma../ x B/sub X//sub ..-->..//sub eta//sub ..pi..//sub ..pi../ are given for other possible states.

Published
1987
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11. Formation of the pseudoscalarsπ0,η, and η’ in the reactionγγ→γγ

Author

D. A. Williams, D. Antreasyan, H. W. Bartels, D. Besset, Ch. Bieler, J. K. Bienlein, A. Bizzeti, E. D. Bloom, I. Brock, K. Brockmüller, R. Cabenda, A. Cartacci, M. Cavalli-Sforza, R. Clare, A. Compagnucci, G. Conforto, S. Cooper, R. Cowan, D. Coyne, G. Drews, A. Engler, K. H. Fairfield, G. Folger, A. Fridman, J. Gaiser, D. Gelphman, G. Glaser, G. Godfrey, F. H. Heimlich, R. Hofstadter, J. Irion, Z. Jakubowski, K. Karch, S. Keh, H. Kilian, I. Kirkbride, T. Kloiber, M. Kobel, W. Koch, A. C. König, K. Königsmann, R. W. Kraemer, S. Krüger, G. Landi, R. Lee, S. Leffler, R. Lekebusch, W. Lockman, S. Lowe, B. Lurz, D. Marlow, H. Marsiske, W. Maschmann, P. McBride, F. Messing, W. J. Metzger, H. Meyer, B. Monteleoni, R. Nernst, B. Niczyporuk, G. Nowak, C. Peck, P. G. Pelfer, B. Pollock, F. C. Porter, D. Prindle, P. Ratoff, M. Reidenbach, B. Renger, C. Rippich, M. Scheer, P. Schmitt, J. Schotanus, J. Schütte, A. Schwarz, F. Selonke, D. Sievers, T. Skwarnicki, V. Stock, K. Strauch, U. Strohbusch, J. Tompkins, H. J. Trost, R. T. Van de Walle, H. Vogel, A. Voigt, U. Volland, K. Wachs, K. Wacker, W. Walk, H. Wegener, and P. Zschorsch

Subjects
Nuclear physics, Physics, Meson, Pi, Resonance, DESY, Storage ring, Crystal Ball, Gamma gamma
Abstract

The Crystal Ball detector has been used at the DORIS II storage ring at DESY to study the reaction e+e−→e+e−γ*γ*→e+e−γγ, where X is a narrow resonance with mass between 100 and 3000 MeV. Formation of π0, η, and η’ mesons is observed, and the following meson partial widths are obtained: Γπ0Γ0→γγ=7.7±0.5±0.5 eV, Γη−γγ=0.514±0.017±0.035 keV, and Γη’→γγ=4.7±0.5±0.5 keV. No other narrow resonances are observed, and upper limits are given for the product ΓX→γγBX→γγ. .AE

Published
1988
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12. Determination ofГ ee of the Υ(1S) and Υ(2S) resonances, and measurement ofR atW=9.39 GeV

Author

D. Antreasyan, G. Landi, F. Messing, T. Kloiber, M. Reidenbach, P. Ratoff, W. Walk, H. Janssen, G. Drews, S. Krüger, H. Meyer, T. Kiel, J. Irion, C. W. Peck, R. Lee, C. Pols, K. Wacker, H. J. Trost, P. Schmitt, David R. Williams, C. Rippich, Elliott D. Bloom, J. Tompkins, B. Muryn, A. Voigt, R. Nernst, H. Marsiske, D. Coyne, D. Marlow, B. Lurz, I. Kirkbride, F. Selonke, Ch Bieler, K. Karch, W. J. Metzger, C. Pegel, B. Niczyporuk, K. Brockmüller, W. Lockmann, D. Sievers, I. C. Brock, G. Conforto, A. Fridman, B. van Uitert, D. Prindle, A. Engler, Robert Hofstadter, K. Graaf, G. Folger, H. Kilian, J. Schütte, F. C. Porter, K. Königsmann, S. Keh, J. Gaiser, M. Scheer, R. T. Van de Walle, K. Fairfield, G. Godfrey, W. Maschmann, R. Clare, J. Schotanus, R. Cabenda, P. Zschorsch, A. Compagnucci, F. H. Heimlich, J. K. Bienlein, P. McBride, K. Strauch, Z. Jakubowski, R. Cowan, R. W. Kraemer, V. Stock, Andrea Bizzeti, U. Strohbusch, Hans J. Vogel, D. Gelphman, M. Kobel, A. Schwarz, S. Lowe, H. W. Bartels, M. Cavalli-Sforza, Grzegorz Nowak, U. Volland, K. Wachs, D. Besset, A. M. Cartacci, G. Glaser, R. Lekebusch, A. C. König, F. H. Heinsius, W. Koch, B. Renger, Tomasz Skwarnicki, S. Leffler, P. G. Pelfer, H. Wegener, B. Monteleoni, B. Pollock, and A. M. Litke

Subjects
Nuclear physics, Physics, Particle decay, Muon, Pair production, Physics and Astronomy (miscellaneous), Meson, Electron–positron annihilation, Hadron, Quarkonium, Engineering (miscellaneous), Crystal Ball
Abstract

Using the Crystal Ball detector operating at the DORIS II storage ring we have measured the leptonic partial widthsГ ee of the Υ(1S) and Υ(2S) resonances. We find $$\Gamma _{ee} (\Upsilon (1S)) = 1.34 \pm 0.03 \pm 0.06keV$$ and $$\Gamma _{ee} (\Upsilon (2S)) = 0.56 \pm 0.04 \pm 0.02keV.$$ The effect onГ ee of applying different prescriptions for radiative corrections is discussed. We also measureR, the ratio of non-resonant hadronic cross section to the Born cross section of μ pair production, at c.m. energyW=9.39 GeV to beR=3.48±0.04±0.16.

Published
1988
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13. The Michel parameter for the decay τ→eν

Author

Ch Bieler, J. Schotanus, A. Compagnucci, K. Strauch, G. Folger, R. Lekebusch, R. Hofstadter, Grzegorz Nowak, U. Volland, K. Königsmann, K. Wachs, H. Janssen, J. Tompkins, P. Zschorsch, S. Leffler, S. Krüger, M. Reidenbach, P. G. Pelfer, Z. Jakubowski, H. Wegener, D. Marlow, K. Graaf, B. Monteleoni, H. Kilian, C. Rippich, H. Marsiske, A. Voigt, T. Kiel, T. Kloiber, M. Cavalli-Sforza, A. Engler, D. Antreasyan, S. Cooper, W. Koch, R. Lee, R. Cowan, J. Irion, B. Niczyporuk, G. Conforto, D. Prindle, W. Lockman, R. W. Krämer, J. Gaiser, Tomasz Skwarnicki, D. Gelphman, I. Kirkbride, W. J. Metzger, K. Wacker, P. Schmitt, F. H. Heimlich, P. Ratoff, D. A. Williams, U. Strohbusch, K. Brockmüller, H. Meyer, C. Peck, A. Fridman, H. J. Trost, Elliott D. Bloom, B. van Uitert, J. K. Bienlein, S. Lowe, G.L. Godfrey, A. M. Litke, B. Lurz, D. Besset, H. Vogel, R. T. Van de Walle, G. Landi, B. Renger, A. M. Cartacci, G. Glaser, A. C. König, D. G. Coyne, F. Messing, H. W. Bartels, F. H. Heinsius, R. Cabenda, F. C. Porter, B. Pollock, J. Schütte, B. Muryn, I. Brock, M. Kobel, A. Schwarz, P. McBride, V. Stock, Andrea Bizzeti, K. Karch, D. Sievers, M. Scheer, R. Nernst, W. Walk, S. Keh, K. Fairfield, W. Maschmann, and R. Clare

Subjects
Physics, Nuclear and High Energy Physics, Lorentz transformation, Elementary particle, DESY, Spectral line, Nuclear physics, symbols.namesake, Particle decay, Pair production, symbols, High Energy Physics::Experiment, Crystal Ball, Lepton
Abstract

The Crystal Ball detector at the Doris II storage ring at DESY has been used to study the electron energy spectrum of the decay τ→evv. In the standard model the Lorentz structure of the decay matrix element is of the well known V-A type, resulting in a Michel parameter of p =0.75. Our spectrum is found to be consistent with this value. A fit yields the value of 0.64±0.07.

Published
1989
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14. Search for exotic tau decays

Author

Ch Bieler, H. Janssen, G. Landi, A. M. Litke, Wesley James Metzger, U. Volland, Tomasz Skwarnicki, M. Reidenbach, P. McBride, W. Koch, G. Nowak, S. Lowe, K. Wachs, D. Antreasyan, I. Kirkbride, F. H. Heimlich, K. Brockmüller, S. Cooper, W. Lockman, P. Zschorsch, A. Fridman, B. van Uitert, H. Meyer, B. Monteleoni, J. Tompkins, H. W. Bartels, Robert Hofstadter, R. Nernst, H. J. Trost, D. Coyne, S. Krüger, R. T. Van de Walle, H. Vogel, B. Renger, I. Brock, F. C. Porter, J. K. Bienlein, Z. Jakubowski, R. Lee, G. Glaser, B. Niczyporuk, R. W. Kraemer, J. Irion, G. Godfrey, B. Muryn, F. H. Heinsius, D. Gelphman, W. Walk, D. Marlow, A. Voigt, V. Stock, S. Leffler, Andrea Bizzeti, P. G. Pelfer, H. Marsiske, R. Cabenda, H. Wegener, D. Prindle, K. Strauch, H. Kilian, K. Wacker, B. Pollock, P. Schmitt, M. Scheer, Elliott D. Bloom, U. Strohbusch, Axel König, K. Karch, D. Sievers, R. Cowan, J. Schutte, B. Lurz, D. Williams, J. Gaiser, M. Kobel, A. Schwarz, T. Kiel, C. W. Peck, G. Conforto, P. N. Ratoff, K. Graaf, C. Rippich, S. Keh, K. Fairfield, W. Maschmann, J. Schotanus, A. Compagnucci, R. Lekebusch, D. Besset, R. Clare, G. Folger, A.M. Cartacci, K. Königsmann, T. Kloiber, A. Engler, M. Cavalli-Sforza, and F. Messing

Subjects
Physics, Nuclear physics, tau lepton, decays, Crystal Ball, Nuclear and High Energy Physics, Particle physics, Detector, DESY, Storage ring
Abstract

The Crystal Ball detector at the Doris II storage ring at DESY was used to search for the exotic decay processes τ →e γ , τ →e π 0 , and τ →e η . No signal was observed. We obtained the following 90% CL upper limits on the branching fractions: B ( τ →e γ ) −4 , B ( τ →e π 0 ) −4 , B ( τ →e η ) −4 .

Published
1988
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16. Search For Radiative Y(1s) Decays Into Light Mesons

Author

R. Lee, G. Folger, P. McBride, B. Muryn, D. Marlow, M. Kobel, G. Landi, A. Schwarz, K. Königsmann, D. Prindle, W. J. Metzger, Ch Bieler, David R. Williams, D. Gelphman, J. Gaiser, Grzegorz Nowak, K. Wacker, P. Schmitt, Tomasz Skwarnicki, M. Reidenbach, S. Krüger, Hans J. Vogel, Elliott D. Bloom, R. Cabenda, C. Rippich, I. Kirkbride, S. Lowe, B. Niczyporuk, U. Strohbusch, Robert Hofstadter, W. Koch, U. Volland, K. Brockmüller, P. Ratoff, B. Pollock, R. W. Kraemer, W. Walk, R. Nernst, A. Fridman, Z. Jakubowski, D. Coyne, K. Wachs, J. Schotanus, B. van Uitert, J. K. Bienlein, H. W. Bartels, A. Compagnucci, D. Besset, R. T. Van de Walle, A. M. Cartacci, G. Glaser, K. Strauch, A. C. König, D. Antreasyan, P. Zschorsch, J. Irion, R. Lekebusch, F. C. Porter, B. Renger, W. Lockman, M. Cavalli-Sforza, S. Cooper, G. Godfrey, J. Schütte, C. W. Peck, S. Keh, K. Fairfield, R. Cowan, W. Maschmann, S. Leffler, G. Conforto, M. Scheer, P. G. Pelfer, H. Marsiske, H. Wegener, R. Clare, F. Messing, T. Kloiber, V. Stock, Andrea Bizzeti, B. Lurz, A. Engler, J. Tompkins, H. Kilian, I. C. Brock, D. Sievers, K. Karch, F. H. Heimlich, B. Monteleoni, H. Meyer, H. J. Trost, and A. Voigt

Subjects
Physics, Annihilation, Physics and Astronomy (miscellaneous), Meson, Branching fraction, Hadron, Upsilon(1S), radiative decays, Crystal Ball, Elementary particle, Quarkonium, Nuclear physics, Particle decay, Pion, High Energy Physics::Experiment, Engineering (miscellaneous)
Abstract

We have searched for radiative decays of the ϒ(1S) resonance, ϒ(1S)→γX, whereX is one of the mesons η, η′f2 (1270),f2 (1720), or a narrow resonance with mass less than 3 GeV/c2 which decays into either π0π0 or ηη. The mesons are identified in their all-neutral decay modes. Since we do not find any such decays, we calculate upper limits on the corresponding branching ratios. These limits are compared to theoretical predictions and to the corresponding branching ratios measured in radiativeJ/Ψ decays.

Published
1988

17. [Premedication in oral surgery]

Author

K, Brockmüller and N, Schwenzer

Subjects
Analgesics, Anesthesia, Dental, Hypnotics and Sedatives, Surgery, Oral
Published
1972

19. SEARCH FOR RADIATIVE B-MESON DECAYS

Author

Ch Bieler, B. Niczyporuk, B. Lurz, K. Wacker, P. Schmitt, Elliott D. Bloom, D. Coyne, S. Leffler, P. G. Pelfer, H. Wegener, Axel König, P. Zschorsch, Grzegorz Nowak, M. Reidenbach, H. Janssen, Robert Hofstadter, K. Karch, S. Lowe, R. T. Van de Walle, U. Strohbusch, A. Voigt, C. W. Peck, F. Messing, M. Kobel, U. Volland, J. Schütte, H. W. Bartels, V. Stock, G. Conforto, S. Cooper, K. Graaf, Andrea Bizzeti, K. Wachs, A. Schwarz, D. Prindle, G. Folger, J. Tompkins, R. Cowan, D. Gelphman, A. Engler, W. Koch, P. McBride, K. Königsmann, W. Walk, C. Rippich, H. Kilian, I. Kirkbride, R. Lee, H. Marsiske, J. Gaiser, I. C. Brock, R. Nernst, T. Skwarnicki, F. H. Heimlich, M. Scheer, J. Schotanus, A. Compagnucci, K. Brockmüller, P. Ratoff, K. Strauch, A. M. Litke, J. Irion, R. Lekebusch, A. Fridman, W. Lockman, B. van Uitert, M. Cavalli-Sforza, G. Godfrey, D. Antreasvan, B. Muryn, D. Sievers, D. Marlow, Helmut Vogel, W. J. Metzger, B. Pollock, D. Besset, A. M. Cartacci, G. Glaser, T. Lesiak, F. H. Heinsius, B. Renger, H. J. Trost, G. Landi, R. Cabenda, R. W. Kraemer, J. K. Bienlein, Z. Jakubowski, Frank C. Porter, B. Monteleoni, T. Kloiber, H. Meyer, S. Krüger, T. Kiel, D. A. Williams, S. Keh, K. Fairfield, W. Maschmann, and R. Clare

Subjects
Physics, Particle physics, Annihilation, Physics and Astronomy (miscellaneous), Meson, Nuclear Theory, Hadron, Elementary particle, B mesons, Quarkonium, Nuclear physics, Pair production, High Energy Physics::Experiment, B meson, radiative decays, Crystal Ball, Nuclear Experiment, Engineering (miscellaneous)
Abstract

The Crystal Ball detector at thee+e− storage ring DORIS-II has been used to search for radiativeB meson decays, especially of the typeb→sγ. No monoenergetic γ-lines have been found in the inclusive photon spectrum from У(4S) decays, and upper limits are obtained for radiative decays ofB mesons to various strange mesons and to theD*. Integrating the photon spectrum over the corresponding energy range, we find $$BR(B \to \gamma X)< 2.8 \times 10^{ - 3} ,$$ at 90% confidence level for the mass range 892 MeV ≦MX≦2045 MeV.

20. The Electron spectrum from B meson decays

Author

B. Niczyporuk, B. Muryn, M. Reidenbach, H. Kilian, M. Scheer, J. Irion, Ch Bieler, K. Graaf, W. Koch, J. Tompkins, T. Skwarnicki, S. Cooper, J. Schotanus, C. Pegel, G. Landi, A. Compagnucci, S. Krüger, K. Wacker, P. Schmitt, K. Strauch, Elliott D. Bloom, T. Kiel, A. Fridman, D. Coyne, Axel König, A. M. Litke, R. Lekebusch, Wesley James Metzger, H. Meyer, U. Strohbusch, H. Marsiske, G. Folger, A.M. Cartacci, Z. Jakubowski, K. Königsmann, R. T. Van de Walle, W. Walk, G. Drews, Grzegorz Nowak, Frank C. Porter, U. Volland, D. Antreasyan, C. W. Peck, K. Wachs, P. McBride, G. Conforto, S. Keh, K. Fairfield, W. Maschmann, G. Glaser, R. Clare, F. Selonke, F. H. Heinsius, J. K. Bienlein, M. Cavalli-Sforza, G. Godfrey, S. Lowe, H. W. Bartels, M. Kobel, I. Kirkbride, A. Schwarz, K. Brockmüller, D. Gelphman, B. van Uitert, V. Stock, Andrea Bizzeti, S. Leffler, P. G. Pelfer, H. Wegener, A. Voigt, B. Lurz, F. H. Heimlich, D. Sievers, B. Monteleoni, Robert Hofstadter, K. Karch, J. Schütte, and David R. Williams

Subjects
Physics, Particle physics, Physics and Astronomy (miscellaneous), Meson, Cabibbo–Kobayashi–Maskawa matrix, Branching fraction, Electron–positron annihilation, B meson, semileptonic decay, CKM matrix, Crystal Ball, Hadron, Nuclear physics, Pair production, Engineering (miscellaneous)
Abstract

The Crystal Ball Collaboration has measured the energy spectrum of electrons from semileptonicB meson decays at thee + e − storage ring DORIS II. Branching ratios and weak mixing angles of the Kobayashi-Maskawa matrix are determined using several models for the hadronic matrix elements. We obtain the branching ratio for semileptonic.B decays to charmed states BR(B→evX c )=(11.7±0.4±1.0)%. Our result for the corresponding Kobayashi-Maskawa matrix element is |V cb |=0.052±0.006. The model dependence of both results is included in the error. We have not observed semileptonicB decays to non-charmed mesons. Analyzing the measured electron spectrum above 2.4 GeV, where nob→c decays contribute, we find BR(B→evX u )/BR(B→evX c )

21. Measurement of pi 0 pi 0 production in two-photon collisions.

Author

Marsiske H, Antreasyan D, Bartels HW, Besset D, Bieler C, Bienlein JK, Bizzeti A, Bloom ED, Brock I I, Brockmüller K, Cabenda R, Cartacci A, Cavalli-Sforza M, Clare R, Compagnucci A, Conforto G, Cooper S, Cowan R, Coyne D, Engler A, Fairfield K, Folger G, Fridman A, Gaiser D, Gelphman D, Glaser G, Godfrey G, Graaf K, Heimlich FH, Heinsius FH, Hofstadter R, Irion J, Jakubowski Z, Janssen H, Karch K, Keh S, Kiel T, Kilian H, Kirkbride I I, Kloiber T, Kobel M, Koch W, König AC, Königsmann K, Kraemer RW, Krüger S, Landi G, Lee R, Leffler S, Lekebusch R, Litke AM, Lockman WS, Lowe S, Lurz B, Marlow D, Maschmann W, McBride P, Messing F, Metzger WJ, Meyer H, Monteleoni B, Muryn B, Nernst R, and Niczyporuk B

Published
1990
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22. Formation of the pseudoscalars pi 0, eta, and eta ' in the reaction gamma gamma --> gamma gamma.

Author

Williams DA, Antreasyan D, Bartels HW, Besset D, Bieler C, Bienlein JK, Bizzeti A, Bloom ED, Brock I I, Brockmüller K, Cabenda R, Cartacci A, Cavalli-Sforza M, Clare R, Compagnucci A, Conforto G, Cooper S, Cowan R, Coyne D, Drews G, Engler A, Fairfield KH, Folger G, Fridman A, Gaiser J, Gelphman D, Glaser G, Godfrey G, Heimlich FH, Hofstadter R, Irion J, Jakubowski Z, Karch K, Keh S, Kilian H, Kirkbride I I, Kloiber T, Kobel M, Koch W, König AC, Königsmann K, Kraemer RW, Krüger S, Landi G, Lee R, Leffler S, Lekebusch R, Lockman W, Lowe S, Lurz B, Marlow D, Marsiske H, Maschmann W, McBride P, Messing F, Metzger WJ, Meyer H, Monteleoni B, Nernst R, Niczyporuk B, Nowak G, Peck C, Pelfer PG, and Pollock B

Published
1988
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23. Measurement of the properties of the eta ' and search for other resonances in gamma gamma --> eta pi 0 pi 0.

Author

Antreasyan D, Bartels HW, Besset D, Bieler C, Bienlein JK, Bizzeti A, Bloom ED, Brock I I, Brockmüller K, Cabenda R, Cartacci A, Cavalli-Sforza M, Clare R, Conforto G, Cooper S, Cowan R, Coyne D, Drews G, Edwards C, Engler A, Fairfield KH, Folger G, Fridman A, Gaiser J, Gelphman D, Glaser G, Godfrey G, Heimlich FH, Hofstadter R, Irion J, Jakubowski Z, Karch K, Keh S, Kilian H, Kirkbride I I, Kloiber T, Kobel M, Koch W, König AC, Königsmann K, Kraemer RW, Krüger S, Landi G, Lee R, Leffler S, Lekebusch R, Litke AM, Lockman W, Lowe S, Lurz B, Marlow D, Marsiske H, Maschmann W, Matsui T, McBride P, Messing F, Metzger WJ, Meyer H, Monteleoni B, Nernst R, Niczyporuk B, Nowak G, Peck C, and Pelfer PG

Published
1987
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24. [Premedication in oral surgery].

Author

Brockmüller K and Schwenzer N

Subjects
Analgesics administration & dosage, Anesthesia, Dental, Hypnotics and Sedatives administration & dosage, Surgery, Oral
Published
1972

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