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Measurement of the tt̄ production cross section in pp̄ collisions at √s=1:96 TeV using kinematic fitting of b-tagged lepton+jet events

Physical Review D Particles Fields Gravitation and Cosmology 71:7 (2005) 1-11

Authors:

D Acosta, J Adelman, T Affolder, T Akimoto, MG Albrow, D Ambrose, S Amerio, D Amidei, A Anastassov, K Anikeev, A Annovi, J Antos, M Aoki, G Apollinari, T Arisawa, JF Arguin, A Artikov, W Ashmanskas, A Attal, F Azfar, P Azzi-Bacchetta, N Bacchetta, H Bachacou, W Badgett, A Barbaro-Galtieri, GJ Barker, VE Barnes, BA Barnett, S Baroiant, M Barone, G Bauer, F Bedeschi, S Behari, S Belforte, G Bellettini, J Bellinger, E Ben-Haim, D Benjamin, A Beretvas, A Bhatti, M Binkley, D Bisello, M Bishai, RE Blair, C Blocker, K Bloom, B Blumenfeld, A Bocci, A Bodek, G Bolla, A Bolshov, PSL Booth, D Bortoletto, J Boudreau, S Bourov, C Bromberg, E Brubaker, J Budagov, HS Budd, K Burkett, G Busetto, P Bussey, KL Byrum, S Cabrera, P Calafiura, M Campanelli, M Campbell, A Canepa, M Casarsa, D Carlsmith, S Carron, R Carosi, M Cavalli-Sforza, A Castro, P Catastini, D Cauz, A Cerri, C Cerri, L Cerrito, J Chapman, C Chen, YC Chen, M Chertok, G Chiarelli, G Chlachidze, F Chlebana, I Cho, K Cho, D Chokheli, ML Chu, S Chuang, JY Chung, WH Chung, YS Chung, CI Ciobanu, MA Ciocci, AG Clark, D Clark, M Coca, A Connolly

Abstract:

We report a measurement of the tt̄ production cross section using the CDF II detector at the Fermilab Tevatron. The data consist of events with an energetic electron or muon, missing transverse energy, and three or more hadronic jets, at least one of which is identified as a b-quark jet by reconstructing a secondary vertex. The background fraction is determined from a fit of the transverse energy of the leading jet. Using 162 ± 10 pb -1 of data, the total cross section is found to be 6.0 ± 1.6(stat.) ± 1.2(syst.) pb, which is consistent with the standard model prediction. © 2005 The American Physical Society.
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Measurement of σ(pp̄→Z)·Br(Z→ττ) at √s=1.96 TeV

Physical Review D - Particles, Fields, Gravitation and Cosmology 71:7 (2005) 1-7

Authors:

VM Abazov, B Abbott, M Abolins, BS Acharya, M Adams, T Adams, M Agelou, JL Agram, SH Ahn, M Ahsan, GD Alexeev, G Alkhazov, A Alton, G Alverson, GA Alves, M Anastasoaie, T Andeen, S Anderson, B Andrieu, Y Arnoud, A Askew, B Åsman, O Atramentov, C Autermann, C Avila, F Badaud, A Baden, B Baldin, PW Balm, S Banerjee, E Barberis, P Bargassa, P Baringer, C Barnes, J Barreto, JF Bartlett, U Bassler, D Bauer, A Bean, S Beauceron, M Begel, A Bellavance, SB Beri, G Bernardi, I Bertram, M Besançon, R Beuselinck, VA Bezzubov, PC Bhat, V Bhatnagar, M Binder, C Biscarat, KM Black, I Blackler, G Blazey, F Blekman, S Blessing, D Bloch, U Blumenschein, A Boehnlein, O Boeriu, TA Bolton, F Borcherding, G Borissov, K Bos, T Bose, A Brandt, R Brock, G Brooijmans, A Bross, NJ Buchanan, D Buchholz, M Buehler, V Buescher, S Burdin, TH Burnett, E Busato, JM Butler, J Bystricky, W Carvalho, BCK Casey, NM Cason, H Castilla-Valdez, S Chakrabarti, D Chakraborty, KM Chan, A Chandra, D Chapin, F Charles, E Cheu, L Chevalier, DK Cho, S Choi, B Choudhary, T Christiansen, L Christofek, D Claes, B Clément, C Clément, Y Coadou

Abstract:

We present a measurement of the cross section for Z production times the branching fraction to τ leptons, σ·Br(Z → τ+τ-), in pp̄ collisions at √s = 1.96 TeV in the channel in which one τ decays into μνμν τ, and the other into hadrons + ντ or eνeντ. The data sample corresponds to an integrated luminosity of 226 pb-1 collected with the D0 detector at the Fermilab Tevatron collider. The final sample contains 2008 candidate events with an estimated background of 55%. From this we obtain σ·Br(Z → τ+τ-) = 237 ± 15(stat) ± 18(sys) ± 15(lum)pb, in agreement with the standard model prediction. © 2005 The American Physical Society.
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Search for first-generation scalar leptoquarks in pp̄ collisions at √s = 1.96 TeV

Physical Review D - Particles, Fields, Gravitation and Cosmology 71:7 (2005) 1-7

Authors:

VM Abazov, B Abbott, M Abolins, BS Acharya, M Adams, T Adams, M Agelou, JL Agram, SH Ahn, M Ahsan, GD Alexeev, G Alkhazov, A Alton, G Alverson, GA Alves, M Anastasoaie, T Andeen, S Anderson, B Andrieu, Y Arnoud, A Askew, B Åsman, O Atramentov, C Autermann, C Avila, F Badaud, A Baden, B Baldin, PW Balm, S Banerjee, E Barberis, P Bargassa, P Baringer, C Barnes, J Barreto, JF Bartlett, U Bassler, D Bauer, A Bean, S Beauceron, M Begel, A Bellavance, SB Beri, G Bernardi, R Bernhard, I Bertram, M Besançon, R Beuselinck, VA Bezzubov, PC Bhat, V Bhatnagar, M Binder, C Biscarat, KM Black, I Blackler, G Blazey, F Blekman, S Blessing, D Bloch, U Blumenschein, A Boehnlein, O Boeriu, TA Bolton, F Borcherding, G Borissov, K Bos, T Bose, A Brandt, R Brock, G Brooijmans, A Bross, NJ Buchanan, D Buchholz, M Buehler, V Buescher, S Burdin, TH Burnett, E Busato, JM Butler, J Bystricky, W Carvalho, BCK Casey, NM Cason, H Castilla-Valdez, S Chakrabarti, D Chakraborty, KM Chan, A Chandra, D Chapin, F Charles, E Cheu, L Chevalier, DK Cho, S Choi, B Choudhary, T Christiansen, L Christofek, D Claes, B Clément, C Clément

Abstract:

We report on a search for pair production of first-generation scalar leptoquarks (LQ) in pp̄ collisions at √s = 1.96 TeV using an integrated luminosity of 252 pb-1 collected at the Fermilab Tevatron collider by the D0 detector. We observe no evidence for LQ production in the topologies arising from LQLQ → eqeq and LQLQ → eqvq, and derive 95% C.L. lower limits on the LQ mass as a function of β, where β is the branching fraction for LQ → eq. The limits are 241 and 218 GeV/c 2 for β = 1 and 0.5, respectively. These results are combined with those obtained by D0 at √s = 1.8 TeV, which increases these LQ mass limits to 256 and 234 GeV/c2. © 2005 The American Physical Society.
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NOvA Proposal to Build a 30 Kiloton Off-Axis Detector to Study Neutrino Oscillations in the Fermilab NuMI Beamline

ArXiv hep-ex/0503053 (2005)

Authors:

The NOvA Collaboration, D Ayres
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Search for CP violation in K0→3π0 decays

Physics Letters Section B Nuclear Elementary Particle and High Energy Physics 610:3-4 (2005) 165-176

Authors:

A Lai, D Marras, JR Batley, RS Dosanjh, TJ Gershon, GE Kalmus, C Lazzeroni, DJ Munday, E Olaiya, MA Parker, TO White, SA Wotton, R Arcidiacono, G Barr, G Bocquet, A Ceccucci, T Cuhadar-Dönszelmann, D Cundy, N Doble, V Falaleev, L Gatignon, A Gonidec, B Gorini, P Grafström, W Kubischta, A Lacourt, I Mikulec, A Norton, B Panzer-Steindel, G Tatishvili, H Wahl, C Cheshkov, P Hristov, V Kekelidze, D Madigojine, N Molokanova, Y Potrebenikov, A Zinchenko, V Martin, P Rubin, R Sacco, A Walker, M Contalbrigo, P Dalpiaz, J Duclos, M Fiorini, PL Frabetti, A Gianoli, M Martini, F Petrucci, M Savrié, A Bizzeti, M Calvetti, G Collazuol, G Graziani, E Iacopini, M Lenti, F Martelli, M Veltri, K Eppard, M Eppard, A Hirstius, K Kleinknecht, U Koch, L Köpke, P Lopes Da Silva, P Marouelli, I Mestvirishvili, I Pellmann, A Peters, SA Schmidt, V Schönharting, Y Schué, R Wanke, A Winhart, M Wittgen, JC Chollet, L Fayard, L Iconomidou-Fayard, G Unal, I Wingerter-Seez, G Anzivino, P Cenci, E Imbergamo, P Lubrano, A Mestvirishvili, A Nappi, M Pepe, M Piccini, R Casali, C Cerri, M Cirilli, F Costantini, R Fantechi, L Fiorini, S Giudici, I Mannelli, G Pierazzini, M Sozzi, JB Cheze

Abstract:

Using data taken during the year 2000 with the NA48 detector at the CERN SPS, a search for the CP violating decay KS→3π0 has been performed. From a fit to the lifetime distribution of about 4.9 million reconstructed K0/K̄0→3π0 decays, the CP violating amplitude η000=A(KS→3π0)/ A(KL→3π0) has been found to be Re(η000)=-0.002±0.011±0.015 and Im(η000)=-0.003±0. 013±0.017. This corresponds to an upper limit on the branching fraction of Br(KS→3π0)<7.4×10-7 at 90% confidence level. The result is used to improve knowledge of Re(ε) and the CPT violating quantity Im(δ) via the Bell-Steinberger relation. © 2005 Elsevier B.V. All rights reserved.
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