Accelerator Neutrinos

Research group

Research theme

Sub department

About

Related research groups

Measurement of the WW production cross section in pp̄ collisions at √s=1.96 TeV

Physical Review Letters 94:15 (2005)

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, 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, 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, T Christiansen, L Christofek, D Claes, B Clément, C Clément, Y Coadou, M Cooke, WE Cooper

Abstract:

We present a measurement of the W boson pair-production cross section in pp̄ collisions at a center-of-mass energy of √s = 1.96 TeV. The data, collected with the Run II D0 detector at Fermilab, correspond to an integrated luminosity of 224-252 pb-1 depending on the final state (ee, eμ, or μμ). We observe 25 candidates with a background expectation of 8.1 ± 0.6(stat) ± 0.6(syst) ± 0.5(1um) events. The probability for an upward fluctuation of the background to produce the observed signal is 2.3 X 10~7, equivalent to 5.2 standard deviations. The measurement yields a cross section of 13.8-3.8+4.3(stat)-0.9+1.2(syst) ±0,9(1um) pb, in agreement with predictions from the standard model. © 2005 The American Physical Society.
More details from the publisher
More details

Search for Anomalous Heavy-Flavor Quark Production in Association with W Bosons

Physical Review Letters 94:15 (2005)

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 search for anomalous production of heavy-flavor quark jets in association with W bosons at the Fermilab Tevatron pp̄ Collider in final states in which the heavy-flavor quark content is enhanced by requiring at least one tagged jet in an event. Jets are tagged using one algorithm based on semileptonic decays of b/c hadrons, and another on their lifetimes. We compare e + jets (164 pb-1) and μ + jets (145 pb-1) channels collected with the D0 detector at √s = 1.96 TeV to expectations from the standard model and set upper limits on anomalous production of such events. © 2005 The American Physical Society.
More details from the publisher
More details

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.
More details from the publisher

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.
More details from the publisher

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.
More details from the publisher