Model-independent measurement of the W-boson helicity in top-quark decays at D0

Physical Review Letters 100:6 (2008)

Authors:

VM Abazov, B Abbott, M Abolins, BS Acharya, M Adams, T Adams, E Aguilo, SH Ahn, M Ahsan, GD Alexeev, G Alkhazov, A Alton, G Alverson, GA Alves, M Anastasoaie, LS Ancu, T Andeen, S Anderson, B Andrieu, MS Anzelc, Y Arnoud, M Arov, M Arthaud, A Askew, B Asman, ACS Assis Jesus, O Atramentov, C Autermann, C Avila, C Ay, F Badaud, A Baden, L Bagby, B Baldin, DV Bandurin, S Banerjee, P Banerjee, E Barberis, AF Barfuss, P Bargassa, P Baringer, J Barreto, JF Bartlett, U Bassler, D Bauer, S Beale, A Bean, M Begalli, M Begel, C Belanger-Champagne, L Bellantoni, A Bellavance, JA Benitez, SB Beri, G Bernardi, R Bernhard, I Bertram, M Besançon, R Beuselinck, VA Bezzubov, PC Bhat, V Bhatnagar, C Biscarat, G Blazey, F Blekman, S Blessing, D Bloch, K Bloom, A Boehnlein, D Boline, TA Bolton, G Borissov, T Bose, A Brandt, R Brock, G Brooijmans, A Bross, D Brown, NJ Buchanan, D Buchholz, M Buehler, V Buescher, V Bunichev, S Burdin, S Burke, TH Burnett, CP Buszello, JM Butler, P Calfayan, S Calvet, J Cammin, W Carvalho, BCK Casey, NM Cason, H Castilla-Valdez, S Chakrabarti, D Chakraborty, KM Chan, K Chan, A Chandra

Abstract:

We present the first model-independent measurement of the helicity of W bosons produced in top quark decays, based on a 1fb-1 sample of candidate tt̄ events in the dilepton and lepton plus jets channels collected by the D0 detector at the Fermilab Tevatron pp̄ Collider. We reconstruct the angle θ* between the momenta of the down-type fermion and the top quark in the W boson rest frame for each top quark decay. A fit of the resulting cos θ* distribution finds that the fraction of longitudinal W bosons f0=0.425±0.166(stat)±0.102(syst) and the fraction of right-handed W bosons f+=0.119±0.090(stat)±0.053(syst), which is consistent at the 30% C.L. with the standard model. © 2008 The American Physical Society.

Search for supersymmetry in di-photon final states at sqrt(s) = 1.96 TeV

Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 659:5 (2008) 856-863

Authors:

VM Abazov, B Abbott, M Abolins, BS Acharya, M Adams, T Adams, E Aguilo, SH Ahn, M Ahsan, GD Alexeev, G Alkhazov, A Alton, G Alverson, GA Alves, M Anastasoaie, LS Ancu, T Andeen, S Anderson, B Andrieu, MS Anzelc, Y Arnoud, M Arov, M Arthaud, A Askew, B Åsman, ACS Assis Jesus, O Atramentov, C Autermann, C Avila, C Ay, F Badaud, A Baden, L Bagby, B Baldin, DV Bandurin, S Banerjee, P Banerjee, E Barberis, AF Barfuss, P Bargassa, P Baringer, J Barreto, JF Bartlett, U Bassler, D Bauer, S Beale, A Bean, M Begalli, M Begel, C Belanger-Champagne, L Bellantoni, A Bellavance, JA Benitez, SB Beri, G Bernardi, R Bernhard, I Bertram, M Besançon, R Beuselinck, VA Bezzubov, PC Bhat, V Bhatnagar, C Biscarat, G Blazey, F Blekman, S Blessing, D Bloch, K Bloom, A Boehnlein, D Boline, TA Bolton, G Borissov, T Bose, A Brandt, R Brock, G Brooijmans, A Bross, D Brown, NJ Buchanan, D Buchholz, M Buehler, V Buescher, S Bunichev, S Burdin, S Burke, TH Burnett, CP Buszello, JM Butler, P Calfayan, S Calvet, J Cammin, W Carvalho, BCK Casey, NM Cason, H Castilla-Valdez, S Chakrabarti, D Chakraborty, KM Chan, K Chan, A Chandra

Abstract:

We report results of a search for supersymmetry (SUSY) with gauge-mediated symmetry breaking in di-photon events collected by the D0 experiment at the Fermilab Tevatron Collider in 2002-2006. In 1.1 fb-1 of data, we find no significant excess beyond the background expected from the standard model and set the most stringent lower limits to date for a standard benchmark model on the lightest neutralino and chargino masses of 125 GeV and 229 GeV, respectively, at 95% confidence. © 2007 Elsevier B.V. All rights reserved.

Erratum: Measurement of σ(pp̄→Z)•Br(Z→ττ) at s=1.96TeV (Physical Review D (2005) 71 (072004))

Physical Review D - Particles, Fields, Gravitation and Cosmology 77:3 (2008)

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 Ãsman, 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

Search for the Higgs boson in events with missing transverse energy and b quark jets produced in proton-antiproton collisions at s**(1/2)=1.96 TeV

ArXiv 0802.0432 (2008)

Authors:

CDF Collaboration, T Aaltonen

Erratum: Measurement of inclusive differential cross sections for Υ(1S) production in pp̄ collisions at s=1.96TeV (Physical Review Letters (2005) 94 (232001))

Physical Review Letters 100:4 (2008)

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, ACS Assis Jesus, 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, S Caron, W Carvalho, BCK Casey, NM Cason, H Castilla-Valdez, S Chakrabarti, D Chakraborty, KM Chan, A Chandra, D Chapin, F Charles, E Cheu, DK Cho, S Choi, B Choudhary, T Christiansen, L Christofek, D Claes, B Clément