M Werlen

Publications (19)0 Total impact

• Article: High transverse momentumη production in π−p, π+p, andpp interactions at 280 GeV/c

  M. Bonesini, E. Bonvin, P. S. L. Booth, R. Bopp, L. J. Carroll, A. J. Cass, D. Cavalli, S. U. Chung, G. Costa, M. Donnat, [......], L. Perini, D. Perrin, G. Polesello, R. Poultney, W. H. Range, L. Rosselet, S. W. Snow, A. S. Thompson, R. M. Turnbull, M. Werlen
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  ABSTRACT: The inclusive cross sections for production by the interactions of 280 GeV/c momentum –, +, and proton beams in hydrogen have been measured. The kinematical range covered is –0.45x F P T x F and transverse momentum respectively. The to 0 cross section ratios are given for the three reactions. The ratio of – p to + p cross sections for production in the above kinematic ranges is 1.220.080.11.
  Zeitschrift für Physik C 11/1989; 42(4):527-532.
• Article: Double prompt photon production at high transverse momentum byπ− on protons at 280 GeV/c

  E. Bonvin, R. Bopp, L. J. Carroll, A. J. Cass, S. U. Chung, M. Donnat, P. A. Dorsaz, M. E. Feliks, L. Fluri, J. N. Jackson, [......], L. Mathys, P. J. Negus, L. Perini, R. Poultney, W. H. Range, L. Rosselet, S. W. Snow, A. S. Thompson, R. M. Turnbull, M. Werlen
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  ABSTRACT: A search for pairs of highp T prompt photons produced in hydrogen by a 280 GeV/c incident - beam has been carried out using a fine-grained electromagnetic calorimeter and the Omega spectrometer at the CERN SPS. Clear evidence for the existence of such events is found with a six standard deviation signal forp T >3.0 GeV/c. The cross-sections are consistent with beyond leading order QCD calculations. A discussion on the determination of s is also presented.
  Zeitschrift für Physik C 11/1989; 41(4):591-598.
• Article: The structure of events triggered by direct photons in π−p, π+p andpp collisions at 280 GeV/c

  M. Bonesini, E. Bonvin, R. Bopp, L. J. Carroll, A. J. Cass, D. Cavalli, G. Costa, S. U. Chung, M. Donnat, P. A. Dorsaz, [......], L. Perini, D. Perrin, R. W. Poultney, W. H. Range, L. Rosselet, S. W. Snow, A. S. Thompson, R. M. Turnbull, J. Wells, M. Werlen
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  ABSTRACT: The structure of events associated with the production of direct photons in – p, + p andpp reactions of 280 GeV/c has been studied using data from the WA 70 experiment at the CERN SPS. Results are presented on the distributions of the fractional momenta of the colliding partons and on the fragmentation of the recoil jet and a comparison is made with predictions using the structure functions of Duke and Owens in the Lund Monte Carlo with string fragmentation.
  Zeitschrift für Physik C 02/1989; 44(1):71-78.
• Article: High transverse momentum prompt photon production by π− and π+ on protons at 280 GeV/c

  M. Bonesini, E. Bonvin, P. S. L. Boóth, D. Bortoletto, L. J. Carroll, A. J. Cass, D. Cavalli, G. Costa, M. Donnat, P. A. Dorsaz, [......], D. Perrin, G. Polesello, W. H. Range, L. Rosselet, S. W. Snow, M. Tamborini, A. S. Thompson, R. M. Turnbull, J. Wells, M. Werlen
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  ABSTRACT: The inclusive cross sections for prompt photon production by – and + on protons have been measured with a beam momentum of 280 GeV/c using a fine grained electromagnetic calorimeter and the CERN Omega spectrometer. The transverse momentum and Feynmanx F ranges covered are 4.0p T x F
  Zeitschrift für Physik C 11/1988; 37(4):535-544.
• Article: High pT trigger electronics for a large orthogonal readout electromagnetic calorimeter

  P. Béné, M. Bonesini, E. Bonvin, J. Bovier, L.J. Carroll, A.J. Cass, D. Cavalli, G. Cecchet, G. Costa, M. Donnat, [......], W.H. Range, J.-P. Richeux, L. Rosselet, A. Rückstuhl, J. Rutschmann, S.W. Snow, A.S. Thompson, R.M. Turnbull, J. Wells, M. Werlen
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  ABSTRACT: A trigger system has been designed and built to select events containing high pT electromagnetic showers detected in a large calorimeter with orthogonal readout. The electronics include analog adders with up to 123 inputs, pulse shapers with 20 ns integration time, 100 MHz flash ADCs and ECL loop-up tables. The total number of input channels is 3072 and the trigger decision is made in about 120 ns.
  Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment.
• Article: A lead-liquid scintillator electromagnetic calorimeter for direct photon physics

  M. Bonesini, E. Bonvin, P.S.L. Booth, D. Bortoletto, L.J. Carroll, A.J. Cass, D. Cavalli, G. Cecchet, G. Costa, M. Donnat, [......], E. Perrin, W.H. Range, L. Rosselet, J. Rutschmann, S.W. Snow, M. Tamborini, A.S. Thompson, R.M. Turnbull, J. Wells, M. Werlen
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  ABSTRACT: A fine-grained sampling electromagnetic calorimeter using liquid scintillator contained in teflon tubes, its associated electronics and reconstruction programs, as used in an experiment on direct photons at CERN, are described. The performance of the system based on three years of operation is discussed.
  Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment.
• Article: Intrinsic transverse momentum in the $\pi^{-}$p --> $\gamma\gamma$X reaction at 280 GeV/c

  E Bonvin, Rudolf Bopp, L J Carroll, A J Cass, S U Chung, Michel Donnat, P A Dorsaz, E Durieux, M E J Feliks, L Fluri, [......], M Martin, L Mathys, P J Negus, R Poultney, W H Range, L Rosselet, S W Snow, A S Thompson, R M Turnbull, M Werlen
• Article: Double prompt photon production at high transverse momentum by $\pi^{-}$ on protons at 280 GeV/c

  E Bonvin, Rudolf Bopp, L J Carroll, A J Cass, S U Chung, Michel Donnat, P A Dorsaz, M E J Feliks, L Fluri, J N Jackson, [......], L Mathys, P J Negus, L Perini, R Poultney, W H Range, L Rosselet, S W Snow, A S Thompson, R M Turnbull, M Werlen
• Article: The contribution of bremsstrahlung $\gamma$ to the high p$_{T}$ $\gamma$ production cross-section in $\pi^{-}$p collisions at 280 GeV/c

  E Bonvin, Rudolf Bopp, L J Caroll, A J Cass, Michel Donnat, P A Dorsaz, E Durieux, M E J Feliks, L Fluri, J N Jackson, [......], M Martin, L Mathys, P J Negus, R Poultney, W H Range, L Rosselet, S W Snow, A S Thompson, R M Turnbull, M Werlen
• Article: Study of the performance of a large sample of Philips photomultipliers type XP2972

  M Bonesini, E Bonvin, P S L Booth, L J Carroll, D Cavalli, G. Cecchet, G Costa, P A Dorsaz, D N Edwards, J R Fischer, [......], D Perrin, W H Range, J Rutschmann, L Rosselet, S W Snow, M Tamborini, A S Thompson, R M Turnbull, J Wells, M Werlen
• Article: High transverse momentum prompt photon production by pi- and pi+ on protons at 280 GeV/c

  M Bonesini, E Bonvin, P S L Booth, Daniela Bortoletto, L J Carroll, A J Cass, D Cavalli, G Costa, Michel Donnat, P A Dorsaz, [......], S Pensotti-Rancoita, L Perini, D Perrin, W H Range, L Rosselet, S W Snow, A S Thompson, R M Turnbull, J Wells, M Werlen
• Article: High transverse momentum pi0 production by pi- and pi+ on protons at 280 GeV/c

  M Bonesini, E Bonvin, P S L Booth, Daniela Bortoletto, L J Carroll, A J Cass, D Cavalli, G Costa, Michel Donnat, P A Dorsaz, [......], D Perrin, G Polesello, W H Range, L Rosselet, S W Snow, M Tamborini, A S Thompson, R M Turnbull, J Wells, M Werlen
• Source

  Available from: Luciano Mandelli

  Article: A 1152 channel timing system for an electromagnetic calorimeter readout

  M Bonesini, E Bonvin, P S L Booth, L J Carroll, A J Cass, D Cavalli, G. Cecchet, G Costa, Michel Donnat, P A Dorsaz, [......], D Perrin, W H Range, L Rosselet, J Rutschmann, S W Snow, M Tamborini, A S Thompson, R M Turnbull, J Wells, M Werlen
• Source

  Available from: Luciano Mandelli

  Article: High p$_{T}$ trigger electronics for a large orthogonal readout electromagnetic calorimeter

  P. Béné, M Bonesini, E Bonvin, J Bovier, L J Carroll, A J Cass, D Cavalli, G. Cecchet, G Costa, Michel Donnat, [......], W H Range, J. P. Richeux, L Rosselet, A Rückstuhl, J Rutschmann, S W Snow, A S Thompson, R M Turnbull, J Wells, M Werlen
• Source

  Available from: Luciano Mandelli

  Article: High transverse momentum $\eta$ production in $\pi^{-}$p, $\pi^{+}$p, and pp interactions at 280 GeV/c

  M Bonesini, E Bonvin, P S L Booth, Rudolf Bopp, L J Carroll, A J Cass, D Cavalli, S U Chung, G Costa, Michel Donnat, [......], L Perini, D Perrin, G Polesello, R Poultney, W H Range, L Rosselet, S W Snow, A S Thompson, R M Turnbull, M Werlen
• Article: Production of high transverse momentum prompt photons and neutral pions in proton-proton interactions at 280 GeV/c

  M Bonesini, E Bonvin, P S L Booth, L J Carroll, A J Cass, D Cavalli, G. Cecchet, G Costa, Michel Donnat, P A Dorsaz, [......], L Perini, D Perrin, G Polesello, W H Range, L Rosselet, S W Snow, A S Thompson, R M Turnbull, J Wells, M Werlen
• Article: Calibration of an electromagnetic calorimeter for direct photon physics

  M Bonesini, E Bonvin, L J Carroll, A J Cass, D Cavalli, G Costa, Michel Donnat, P A Dorsaz, D N Edwards, J R Fischer, [......], S Pensotti-Rancoita, L Perini, D Perrin, W H Range, L Rosselet, S W Snow, A S Thompson, R M Turnbull, J Wells, M Werlen
• Source

  Available from: Emmanuel Bonvin

  Article: Prompt photon production by pi- and pi+ on protons at 280 GeV

  M Bonesini, E Bonvin, Daniela Bortoletto, P S L Booth, L J Carroll, A J Cass, D Cavalli, G. Cecchet, G Costa, Michel Donnat, [......], L Perini, W H Range, L Rosselet, J Rutschmann, S W Snow, M Tamborini, A S Thompson, R M Turnbull, J Wells, M Werlen
• Article: Intrinsic transverse momentum in the π−p→γγX reaction at 280 GeV/c

  E. Bonvin, R. Bopp, L.J. Carroll, A.J. Cass, S.U. Chung, M. Donnat, P.A. Dorsaz, E. Durieux, M.E. Feliks, L. Fluri, [......], M. Martin, L. Mathys, P.J. Negus, R. Poultney, W.H. Range, L. Rosselet, S.W. Snow, A.S. Thompson, R.M. Turnbull, M. Werlen
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  ABSTRACT: The correlation between the two high transverse momentum (pt2.75 GeV/c) photons of the reaction π−p→γγX is studied at the beam momentum of 280 GeV/c. QCD calculations beyond leading logarithms are not sufficient to explain the width of the distributions and the effects due to intrinsic transverse momentum of the incident partons are discussed.
  Physics Letters B.