Search for the flavor-changing neutral-current decay t→Zq in pp̄ collisions at s=1.96TeV

Physical Review Letters 101:19 (2008)

Authors:

T Aaltonen, J Adelman, T Akimoto, MG Albrow, B Álvarez González, S Amerio, D Amidei, A Anastassov, A Annovi, J Antos, G Apollinari, A Apresyan, T Arisawa, A Artikov, W Ashmanskas, A Attal, A Aurisano, F Azfar, P Azzurri, W Badgett, A Barbaro-Galtieri, VE Barnes, BA Barnett, V Bartsch, G Bauer, PH Beauchemin, F Bedeschi, P Bednar, D Beecher, S Behari, G Bellettini, J Bellinger, D Benjamin, A Beretvas, J Beringer, A Bhatti, M Binkley, D Bisello, I Bizjak, RE Blair, C Blocker, B Blumenfeld, A Bocci, A Bodek, V Boisvert, G Bolla, D Bortoletto, J Boudreau, A Boveia, B Brau, A Bridgeman, L Brigliadori, C Bromberg, E Brubaker, J Budagov, HS Budd, S Budd, K Burkett, G Busetto, P Bussey, A Buzatu, KL Byrum, S Cabrera, C Calancha, M Campanelli, M Campbell, F Canelli, A Canepa, D Carlsmith, R Carosi, S Carrillo, S Carron, B Casal, M Casarsa, A Castro, P Catastini, D Cauz, V Cavaliere, M Cavalli-Sforza, A Cerri, L Cerrito, SH Chang, YC Chen, M Chertok, G Chiarelli, G Chlachidze, F Chlebana, K Cho, D Chokheli, JP Chou, G Choudalakis, SH Chuang, K Chung, WH Chung, YS Chung, CI Ciobanu, MA Ciocci, A Clark, D Clark, G Compostella

Abstract:

We report a search for the flavor-changing neutral-current decay of the top quark t→Zq (q=u, c) in pp̄ collisions at s=1.96TeV using a data sample corresponding to an integrated luminosity of 1.9fb-1 collected by the CDF II detector. This decay is strongly suppressed in the standard model and an observation of a signal at the Fermilab Tevatron would be an indication of physics beyond the standard model. Using Z+4 jet final state candidate events, with and without an identified bottom quark jet, we obtain an upper limit of B(t→Zq)<3.7% at 95% C.L. © 2008 The American Physical Society.

Measurement of beauty production from dimuon events at HERA

ArXiv 0811.0894 (2008)

Authors:

ZEUS Collaboration, S Chekanov

Measurement of the forward-backward charge asymmetry and extraction of sin2θWeff in pp̄→Z/γ*+X→e+e-+X events produced at s=1.96TeV

Physical Review Letters 101:19 (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, M Aoki, Y Arnoud, M Arov, M Arthaud, A Askew, B Åsman, ACSA Jesus, O Atramentov, C Avila, F Badaud, A Baden, L Bagby, B Baldin, DV Bandurin, P Banerjee, S 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, EE Boos, 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, H Castilla-Valdez, S Chakrabarti, D Chakraborty, K Chan, KM Chan, A Chandra, F Charles

Abstract:

We present a measurement of the forward-backward charge asymmetry (AFB) in pp̄→Z/γ*+X→e+e-+X events at a center-of-mass energy of 1.96 TeV using 1.1fb-1 of data collected with the D0 detector at the Fermilab Tevatron collider. AFB is measured as a function of the invariant mass of the electron-positron pair, and found to be consistent with the standard model prediction. We use the AFB measurement to extract the effective weak mixing angle sin2θWeff=0.2326±0.0018(stat)±0.0006(syst). © 2008 The American Physical Society.

Top Quark Mass Measurement in the tt-bar All Hadronic Channel using a Matrix Element Technique in ppbar Collisions at sqrt s = 1.96 TeV

ArXiv 0811.1062 (2008)

Authors:

CDF Collaboration, T Aaltonen

Measurement of W-Boson Helicity Fractions in Top-Quark Decays Using costheta*

ArXiv 0811.0344 (2008)