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New upper limit on the decay [Formula presented]

Physical Review D Particles Fields Gravitation and Cosmology 56:9 (1997) 5359-5365

Authors:

TE Browder, F Li, Y Li, JL Rodriguez, T Bergfeld, BI Eisenstein, J Ernst, GE Gladding, GD Gollin, RM Hans, E Johnson, I Karliner, MA Marsh, M Palmer, M Selen, JJ Thaler, KW Edwards, A Bellerive, R Janicek, DB MacFarlane, KW McLean, PM Patel, AJ Sadoff, R Ammar, P Baringer, A Bean, D Besson, D Coppage, C Darling, R Davis, N Hancock, S Kotov, I Kravchenko, N Kwak, S Anderson, Y Kubota, M Lattery, SJ Lee, JJ O’Neill, S Patton, R Poling, T Riehle, V Savinov, A Smith, MS Alam, SB Athar, Z Ling, AH Mahmood, H Severini, S Timm, F Wappler, A Anastassov, S Blinov, JE Duboscq, KD Fisher, D Fujino, KK Gan, T Hart, K Honscheid, H Kagan, R Kass, J Lee, MB Spencer, M Sung, A Undrus, R Wanke, A Wolf, MM Zoeller, B Nemati, SJ Richichi, WR Ross, P Skubic, M Bishai, J Fast, E Gerndt, JW Hinson, N Menon, DH Miller, EI Shibata, IPJ Shipsey, M Yurko, L Gibbons, S Glenn, SD Johnson, Y Kwon, S Roberts, EH Thorndike, CP Jessop, K Lingel, H Marsiske, ML Perl, D Ugolini, R Wang, X Zhou, TE Coan, V Fadeyev, I Korolkov, Y Maravin, I Narsky, V Shelkov

Abstract:

We have searched for the rare decay of the [Formula presented] meson [Formula presented] using the CLEO II detector. The [Formula presented]’s were produced in [Formula presented] collisions with 10 GeV center-of-mass energy at the Cornell Electron Storage Ring (CESR). We find with [Formula presented] confidence the upper limit on the branching fraction [Formula presented]. The application of conventional elementary particle theory to this decay predicts a branching fraction of about [Formula presented]. © 1997 The American Physical Society.

Nonequilibrium evolution of a trapped Bose gas

Conference on Quantum Electronics and Laser Science QELS Technical Digest Series 12 (1997) 28-29

Authors:

H Wu, E Arimondo, CJ Foot

Abstract:

An investigation focusing on the nonequilibrium evolution of a trapped Bose gas revealed that the formation of a Bose gas can be classified into three stages, namely: kinetic evolution; the formation of short range order; and the off-diagonal long-range order. Using a homogeneous gas consisting of sodium atoms. The evolution of non-Gaussian velocity distribution was observed. This indicates the accumulation of Bose particles at low energy states, but not necessarily the signature of the appearance of a macroscopic Bose-Einstein condensate. The condensate fraction will be very small when the ensemble of sodium atoms magnetically trapped in a harmonic potential is considered.

Properties of jets in W boson events from 1.8 TeV p̄ p collisions

Physical Review Letters 79:24 (1997) 4760-4765

Authors:

F Abe, H Akimoto, A Akopian, MG Albrow, SR Amendolia, D Amidei, J Antos, S Aota, G Apollinari, T Arisawa, T Asakawa, W Ashmanskas, M Atac, F Azfar, P Azzi-Bacchetta, N Bacchetta, W Badgett, S Bagdasarov, MW Bailey, J Bao, P de Barbaro, A Barbaro-Galtieri, VE Barnes, BA Barnett, M Barone, E Barzi, G Bauer, T Baumann, F Bedeschi, S Behrends, S Belforte, G Bellettini, J Bellinger, D Benjamin, J Benlloch, J Bensinger, D Benton, A Beretvas, JP Berge, J Berryhill, S Bertolucci, S Bettelli, B Bevensee, A Bhatti, K Biery, M Binkley, D Bisello, RE Blair, C Blocker, S Blusk, A Bodek, W Bokhari, G Bolla, V Bolognesi, Y Bonushkin, D Bortoletto, J Boudreau, L Breccia, C Bromberg, N Bruner, E Buckley-Geer, HS Budd, K Burkett, G Busetto, A Byon-Wagner, KL Byrum, C Campagnari, M Campbell, A Caner, W Carithers, D Carlsmith, J Cassada, A Castro, D Cauz, Y Cen, A Cerri, F Cervelli, PS Chang, PT Chang, HY Chao, J Chapman, MT Cheng, M Chertok, G Chiarelli, T Chikamatsu, CN Chiou, L Christofek, S Cihangir, AG Clark, M Cobal, E Cocca, M Contreras, J Conway, J Cooper, M Cordelli, C Couyoumtzelis, D Crane, D Cronin-Hennessy, R Culbertson, T Daniels

Abstract:

We present a study of events with W bosons and hadronic jets produced in p̄p collisions at a center of mass energy of 1.8 TeV. The data consist of 51 400 W± → e± decay candidates from 108 pb-1 of integrated luminosity collected using the CDF detector at the Fermilab Tevatron Collider. Cross sections and jet production properties have been measured for W + ≥1 to ≥4 jet events. The data are compared to predictions of leading-order QCD matrix element calculations with added gluon radiation and simulated parton fragmentation.

Properties of six-jet events with large six-jet mass at the Fermilab proton-antiproton collider

Physical Review D - Particles, Fields, Gravitation and Cosmology 56:5 (1997) 2532-2543

Authors:

F Abe, H Akimoto, A Akopian, MG Albrow, SR Amendolia, D Amidei, J Antos, S Aota, G Apollinari, T Asakawa, W Ashmanskas, M Atac, F Azfar, P Azzi-Bacchetta, N Bacchetta, W Badgett, S Bagdasarov, MW Bailey, J Bao, P de Barbaro, A Barbaro-Galtieri, VE Barnes, BA Barnett, M Barone, E Barzi, G Bauer, T Baumann, F Bedeschi, S Behrends, S Belforte, G Bellettini, J Bellinger, D Benjamin, J Benlloch, J Bensinger, D Benton, A Beretvas, JP Berge, J Berryhill, S Bertolucci, B Bevensee, A Bhatti, K Biery, M Binkley, D Bisello, RE Blair, C Blocker, A Bodek, W Bokhari, V Bolognesi, G Bolla, D Bortoletto, J Boudreau, L Breccia, C Bromberg, N Bruner, E Buckley-Geer, HS Budd, K Burkett, G Busetto, A Byon-Wagner, KL Byrum, J Cammerata, C Campagnari, M Campbell, A Caner, W Carithers, D Carlsmith, A Castro, D Cauz, Y Cen, F Cervelli, PS Chang, PT Chang, HY Chao, J Chapman, MT Cheng, G Chiarelli, T Chikamatsu, CN Chiou, L Christofek, S Cihangir, AG Clark, M Cobal, E Cocca, M Contreras, J Conway, J Cooper, M Cordelli, C Couyoumtzelis, D Crane, D Cronin-Hennessy, R Culbertson, T Daniels, F DeJongh, S Delchamps, S Dell’Agnello, M Dell’Orso, R Demina, L Demortier

Abstract:

We describe the properties of six-jet events, with the six-jet mass exceeding [Formula presented] produced at the Fermilab proton-antiproton collider operating at a center-of-mass energy of 1.8 TeV. Observed distributions for a set of 20 multijet variables are compared with predictions from the HERWIG QCD parton shower Monte Carlo program, the NJETS leading order QCD matrix element Monte Carlo program, and a phase-space model in which six-jet events are distributed uniformly over the kinematically allowed region of the six-body phase space. In general the QCD predictions provide a good description of the observed six-jet distributions. © 1997 The American Physical Society.

Search for charged higgs boson decays of the top quark using hadronic decays of the tau lepton

Physical Review Letters 79:3 (1997) 357-362

Authors:

F Abe, H Akimoto, A Akopian, MG Albrow, SR Amendolia, D Amidei, J Antos, S Aota, G Apollinari, T Asakawa, W Ashmanskas, M Atac, F Azfar, P Azzi-Bacchetta, N Bacchetta, W Badgett, S Bagdasarov, MW Bailey, J Bao, P de Barbaro, A Barbaro-Galtieri, VE Barnes, B Barnett, M Barone, E Barzi, G Bauer, T Baumann, F Bedeschi, S Behrends, S Belforte, G Bellettini, J Bellinger, D Benjamin, J Benlloch, J Bensinger, D Benton, A Beretvas, JP Berge, J Berryhill, S Bertolucci, B Bevensee, A Bhatti, K Biery, M Binkley, D Bisello, RE Blair, C Blocker, A Bodek, W Bokhari, V Bolognesi, G Bolla, D Bortoletto, J Boudreau, L Breccia, C Bromberg, N Bruner, E Buckley-Geer, HS Budd, K Burkett, G Busetto, A Byon-Wagner, KL Byrum, J Cammerata, C Campagnari, M Campbell, A Caner, W Carithers, D Carlsmith, A Castro, D Cauz, Y Cen, F Cervelli, PS Chang, PT Chang, HY Chao, J Chapman, MT Cheng, G Chiarelli, T Chikamatsu, CN Chiou, L Christofek, S Cihangir, AG Clark, M Cobal, E Cocca, M Contreras, J Conway, J Cooper, M Cordelli, C Couyoumtzelis, D Crane, D Cronin-Hennessy, R Culbertson, T Daniels, F De Jongh, S Delchamps, S Dell-Agnello, M Dell-Orso, R Demina, L Demortier

Abstract:

This Letter describes a direct search for charged Higgs boson production in proton-antiproton collisions at sqrt(s)=1.8 TeV recorded by the Collider Detector at Fermilab. Two-Higgs-doublet extensions to the standard model predict the existence of charged Higgs bosons. In such models, the branching fraction for top quarks B(t → H b → tau nu b) can be large. This search uses the hadronic decays of the tau lepton in this channel to significantly extend previous limits on charged Higgs production. © 1997 The American Physical Society.