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Search for new particles decaying to tt̄ in pp̄ collisions at √s = 1.8 TeV

Physical Review Letters 85:10 (2000) 2062-2067

Authors:

T Affolder, H Akimoto, A Akopian, MG Albrow, P Amaral, SR Amendolia, D Amidei, K Anikeev, J Antos, G Apollinari, T Arisawa, T Asakawa, W Ashmanskas, M Atac, F Azfar, P Azzi-Bacchetta, N Bacchetta, MW Bailey, S Bailey, P de Barbaro, A Barbaro-Galtieri, VE Barnes, BA Barnett, M Barone, G Bauer, F Bedeschi, S Belforte, G Bellettini, J Bellinger, D Benjamin, J Bensinger, A Beretvas, JP Berge, J Berryhill, B Bevensee, A Bhatti, M Binkley, D Bisello, RE Blair, C Blocker, K Bloom, B Blumenfeld, SR Blusk, A Bocci, A Bodek, W Bokhari, G Bolla, Y Bonushkin, D Bortoletto, J Boudreau, A Brandl, S van den Brink, C Bromberg, M Brozovic, N Bruner, E Buckley-Geer, J Budagov, HS Budd, K Burkett, G Busetto, A Byon-Wagner, KL Byrum, M Campbell, W Carithers, J Carlson, D Carlsmith, J Cassada, A Castro, D Cauz, A Cerri, AW Chan, PS Chang, PT Chang, J Chapman, C Chen, YC Chen, MT Cheng, M Chertok, G Chiarelli, I Chirikov-Zorin, G Chlachidze, F Chlebana, L Christofek, ML Chu, S Cihangir, CI Ciobanu, AG Clark, A Connolly, J Conway, J Cooper, M Cordelli, J Cranshaw, D Cronin-Hennessy, R Cropp, R Culbertson, D Dagenhart, F de Jongh, S dell'Agnello, M dell'Orso, R Demina

Abstract:

The search for narrow-width vector particles was undertaken using 106 pb-1 data from the collider detector at Fermilab. The cross section upper limits for narrow vector resonances decaying to tt are presented. The existence of leptophobic Z boson was not included in the top-color-assisted technicolor model at the 95% confidence level.

Search for second and third generation leptoquarks including production via technicolor interactions in pp̄ collisions at √s = 1.8 TeV

Physical Review Letters 85:10 (2000) 2056-2061

Authors:

T Affolder, H Akimoto, A Akopian, MG Albrow, P Amaral, SR Amendolia, D Amidei, K Anikeev, J Antos, G Apollinari, T Arisawa, T Asakawa, W Ashmanskas, M Atac, F Azfar, P Azzi-Bacchetta, N Bacchetta, MW Bailey, S Bailey, P de Barbaro, A Barbaro-Galtieri, VE Barnes, BA Barnett, M Barone, G Bauer, F Bedeschi, S Belforte, G Bellettini, J Bellinger, D Benjamin, J Bensinger, A Beretvas, JP Berge, J Berryhill, B Bevensee, A Bhatti, M Binkley, D Bisello, RE Blair, C Blocker, K Bloom, B Blumenfeld, SR Blusk, A Bocci, A Bodek, W Bokhari, G Bolla, Y Bonushkin, D Bortoletto, J Boudreau, A Brandl, S van den Brink, C Bromberg, M Brozovic, N Bruner, E Buckley-Geer, J Budagov, HS Budd, K Burkett, G Busetto, A Byon-Wagner, KL Byrum, P Calafiura, M Campbell, W Carithers, J Carlson, D Carlsmith, J Cassada, A Castro, D Cauz, A Cerri, AW Chan, PS Chang, PT Chang, J Chapman, C Chen, YC Chen, MT Cheng, M Chertok, G Chiarelli, I Chirikov-Zorin, G Chlachidze, F Chlebana, L Christofek, ML Chu, CI Ciobanu, AG Clark, A Connolly, J Conway, J Cooper, M Cordelli, J Cranshaw, D Cronin-Hennessy, R Cropp, R Culbertson, D Dagenhart, F de Jongh, S dell'Agnello, M dell'Orso, R Demina

Abstract:

The collider detector at Fermilab was used to examine second and third generation leptoquarks. The potential production of color triplet technipions in strongly-coupled color octet technirhos decays was examined. Events with heavy flavor jets and missing energy may indicate the second-generation leptoquark decay to a charm quark and neutrino. Since there were no excess of events above standard model predictions, 95% confidence level limits were determined.

51ÁÔÆæÈë¿Ú of exclusive two-body B0 meson decays to charmonium

Physical Review D Particles Fields Gravitation and Cosmology 62:5 (2000) 1-5

Authors:

P Avery, C Prescott, AI Rubiera, J Yelton, J Zheng, G Brandenburg, A Ershov, YS Gao, DYJ Kim, R Wilson, TE Browder, Y Li, JL Rodriguez, H Yamamoto, T Bergfeld, BI Eisenstein, J Ernst, GE Gladding, GD Gollin, RM Hans, E Johnson, I Karliner, MA Marsh, M Palmer, C Plager, C Sedlack, M Selen, JJ Thaler, J Williams, KW Edwards, R Janicek, PM Patel, AJ Sadoff, R Ammar, A Bean, D Besson, R Davis, N Kwak, X Zhao, S Anderson, VV Frolov, Y Kubota, SJ Lee, R Mahapatra, JJ O'Neill, R Poling, T Riehle, A Smith, CJ Stepaniak, J Urheim, S Ahmed, MS Alam, SB Athar, L Jian, L Ling, M Saleem, S Timm, F Wappler, A Anastassov, JE Duboscq, E Eckhart, KK Gan, C Gwon, T Hart, K Honscheid, D Hufnagel, H Kagan, R Kass, TK Pedlar, H Schwarthoff, JB Thayer, E Von Toerne, MM Zoeller, SJ Richichi, H Severini, P Skubic, A Undrus, S Chen, J Fast, JW Hinson, J Lee, DH Miller, EI Shibata, IPJ Shipsey, V Pavlunin, D Cronin-Hennessy, AL Lyon, EH Thorndike, CP Jessop, H Marsiske, ML Perl, V Savinov, D Ugolini, X Zhou, TE Coan, V Fadeyev, Y Maravin, I Narsky, R Stroynowski, J Ye

Abstract:

We present a study of three B0 decay modes useful for time-dependent CP asymmetry measurements. From a sample of 9.7×106 BBÌ„ meson pairs collected with the CLEO detector, we have reconstructed B0 →J/ψ°­S0, B0→χclKS0, and B0→J/ψπ0 decays. The latter two decay modes have been observed for the first time. We describe a KS0→϶Ä0Ï€0 detection technique and its application to the reconstruction of the decay B0 →J/ψ°­S0. Combining the results obtained using KS0→϶Ä+Ï€- and KS0→϶Ä0Ï€0 decays, we determine B(B0 →J/ψ°­0)=(9.5±0.8±0.6)×10-4, where the first uncertainty is statistical and the second one is systematic. We also obtain B(B0→χclK0)=(3.9-1.3 +1.9±0.4)×10-4 and B(B0→J/ψπ0)=(2.5-0.9 +1.1±0.2)×10-5. ©2000 The American Physical Society.

Compact hyperbolic extra dimensions: branes, kaluza-klein modes, and cosmology.

Phys Rev Lett 85:5 (2000) 928-931

Authors:

N Kaloper, J March-Russell, GD Starkman, M Trodden

Abstract:

We reconsider theories with low gravitational (or string) scale M(*) where Newton's constant is generated via new large-volume spatial dimensions, while standard model states are localized to a 3-brane. Utilizing compact hyperbolic manifolds we show that the spectrum of Kaluza-Klein modes is radically altered. This allows the early Universe to evolve normally up to substantial temperatures, and completely negates the astrophysical constraints on M(*). Furthermore, an exponential hierarchy between the usual Planck scale and the true fundamental scale of physics can emerge with only O(1) coefficients. The linear size of the internal space remains small. The proposal has striking testable signatures.

Observation of harmonic generation and nonlinear coupling in the collective dynamics of a bose-einstein condensate.

Phys Rev Lett 85:4 (2000) 692-695

Authors:

G Hechenblaikner, OM Marago, E Hodby, J Arlt, S Hopkins, CJ Foot

Abstract:

We report the observation of harmonic generation and strong nonlinear coupling of two collective modes of a condensed gas of rubidium atoms. Using a modified time averaged orbiting potential trap we changed the trap anisotropy to a value where the frequency of the m = 0 high-lying mode corresponds to twice the frequency of the m = 0 low-lying mode, thus leading to strong nonlinear coupling between these modes. By changing the anisotropy of the trap and exciting the low-lying mode we observed significant frequency shifts of this fundamental mode and also the generation of its second harmonic.