ATLAS

Research group

Research theme

Sub department

About

Related research groups

Measurement of the W boson helicity in top quark decays at D0

Physical Review D - Particles, Fields, Gravitation and Cosmology 75:3 (2007)

Authors:

VM Abazov, B Abbott, M Abolins, BS Acharya, M Adams, T Adams, M Agelou, E Aguilo, SH Ahn, M Ahsan, GD Alexeev, G Alkhazov, A Alton, G Alverson, GA Alves, M Anastasoaie, T Andeen, S Anderson, B Andrieu, MS Anzelc, Y Arnoud, M Arov, 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, P Banerjee, S Banerjee, E Barberis, P Bargassa, P Baringer, C Barnes, 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, L Berntzon, 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, K Bloom, U Blumenschein, A Boehnlein, O Boeriu, TA Bolton, G Borissov, K Bos, T Bose, A Brandt, R Brock, G Brooijmans, A Bross, D Brown, NJ Buchanan, D Buchholz, M Buehler, V Buescher, S Burdin, S Burke, TH Burnett, E Busato, CP Buszello, JM Butler, P Calfayan, S Calvet, J Cammin, S Caron, W Carvalho, BCK Casey, NM Cason

Abstract:

We present a measurement of the fraction f+ of right-handed W bosons produced in top quark decays, based on a candidate sample of tt̄ events in the +jets and dilepton decay channels corresponding to an integrated luminosity of 370pb-1 collected by the D0 detector at the Fermilab Tevatron pp̄ Collider at s=1.96TeV. We reconstruct the decay angle θ* for each lepton. By comparing the cos θ* distribution from the data with that for the expected background and signal for various values of f+ (where we assume that the fraction of longitudinally-polarized W bosons has the standard model value of 0.70), we find f+=0.056±0.080(stat)±0.057(syst) (f+<0.23 at 95% C.L.), consistent with the standard model prediction of f+=3.6×10-4. © 2007 The American Physical Society.
More details from the publisher
More details

Search for invisible decays of the Υ(1S) resonance

Physical Review D American Physical Society (APS) 75:3 (2007) 031104

Authors:

P Rubin, C Cawlfield, BI Eisenstein, I Karliner, D Kim, N Lowrey, P Naik, M Selen, EJ White, J Wiss, RE Mitchell, MR Shepherd, D Besson, TK Pedlar, D Cronin-Hennessy, KY Gao, J Hietala, Y Kubota, T Klein, BW Lang, R Poling, AW Scott, A Smith, P Zweber, S Dobbs, Z Metreveli, KK Seth, A Tomaradze, J Ernst, KM Ecklund, H Severini, W Love, V Savinov, O Aquines, Z Li, A Lopez, S Mehrabyan, H Mendez, J Ramirez, GS Huang, DH Miller, V Pavlunin, B Sanghi, IPJ Shipsey, B Xin, GS Adams, M Anderson, JP Cummings, I Danko, D Hu, B Moziak, J Napolitano, Q He, J Insler, H Muramatsu, CS Park, EH Thorndike, F Yang, TE Coan, YS Gao, M Artuso, S Blusk, J Butt, J Li, N Menaa, R Mountain, S Nisar, K Randrianarivony, R Sia, T Skwarnicki, S Stone, JC Wang, K Zhang, G Bonvicini, D Cinabro, M Dubrovin, A Lincoln, DM Asner, KW Edwards, RA Briere, T Ferguson, G Tatishvili, H Vogel, ME Watkins, JL Rosner, NE Adam, JP Alexander, DG Cassel, JE Duboscq, R Ehrlich, L Fields, RS Galik, L Gibbons, R Gray, SW Gray, DL Hartill, BK Heltsley, D Hertz, CD Jones, J Kandaswamy, DL Kreinick, VE Kuznetsov, H Mahlke-Krüger, PUE Onyisi, JR Patterson, D Peterson, J Pivarski, D Riley, A Ryd, AJ Sadoff, H Schwarthoff, X Shi, S Stroiney, WM Sun, T Wilksen, SB Athar, R Patel, V Potlia, J Yelton
More details from the publisher

W boson measurements at the tevatron

Acta Physica Polonica B 38:2 PART 1 (2007) 391-399

Abstract:

I present recent Tevatron Run II results from CDF and DØ on the production and decay properties of the W boson.

χcJ decays to h+h-h0

Physical Review D American Physical Society (APS) 75:3 (2007) 032002

Authors:

SB Athar, R Patel, V Potlia, J Yelton, P Rubin, C Cawlfield, BI Eisenstein, I Karliner, D Kim, N Lowrey, P Naik, M Selen, EJ White, J Wiss, RE Mitchell, MR Shepherd, D Besson, TK Pedlar, D Cronin-Hennessy, KY Gao, J Hietala, Y Kubota, T Klein, BW Lang, R Poling, AW Scott, A Smith, P Zweber, S Dobbs, Z Metreveli, KK Seth, A Tomaradze, J Ernst, KM Ecklund, H Severini, W Love, V Savinov, O Aquines, Z Li, A Lopez, S Mehrabyan, H Mendez, J Ramirez, GS Huang, DH Miller, V Pavlunin, B Sanghi, IPJ Shipsey, B Xin, GS Adams, M Anderson, JP Cummings, I Danko, D Hu, B Moziak, J Napolitano, Q He, J Insler, H Muramatsu, CS Park, EH Thorndike, F Yang, TE Coan, YS Gao, M Artuso, S Blusk, J Butt, J Li, N Menaa, R Mountain, S Nisar, K Randrianarivony, R Sia, T Skwarnicki, S Stone, JC Wang, K Zhang, G Bonvicini, D Cinabro, M Dubrovin, A Lincoln, DM Asner, KW Edwards, RA Briere, T Ferguson, G Tatishvili, H Vogel, ME Watkins, JL Rosner, NE Adam, JP Alexander, DG Cassel, JE Duboscq, R Ehrlich, L Fields, L Gibbons, R Gray, SW Gray, DL Hartill, BK Heltsley, D Hertz, CD Jones, J Kandaswamy, DL Kreinick, VE Kuznetsov, H Mahlke-Krüger, PUE Onyisi, JR Patterson, D Peterson, J Pivarski, D Riley, A Ryd, AJ Sadoff, H Schwarthoff, X Shi, S Stroiney, WM Sun, T Wilksen, M Weinberger
More details from the publisher

Observation of Upsilon(3S)-->tau+tau- and tests of lepton universality in Upsilon decays.

Physical review letters 98:5 (2007) 052002

Authors:

D Besson, TK Pedlar, D Cronin-Hennessy, KY Gao, DT Gong, J Hietala, Y Kubota, T Klein, BW Lang, R Poling, AW Scott, A Smith, P Zweber, S Dobbs, Z Metreveli, KK Seth, A Tomaradze, J Ernst, H Severini, SA Dytman, W Love, V Savinov, O Aquines, Z Li, A Lopez, S Mehrabyan, H Mendez, J Ramirez, GS Huang, DH Miller, V Pavlunin, B Sanghi, IPJ Shipsey, B Xin, GS Adams, M Anderson, JP Cummings, I Danko, J Napolitano, Q He, J Insler, H Muramatsu, CS Park, EH Thorndike, F Yang, TE Coan, YS Gao, F Liu, M Artuso, S Blusk, J Butt, N Horwitz, J Li, N Menaa, R Mountain, S Nisar, K Randrianarivony, R Redjimi, R Sia, T Skwarnicki, S Stone, JC Wang, K Zhang, SE Csorna, G Bonvicini, D Cinabro, M Dubrovin, A Lincoln, DM Asner, KW Edwards, RA Briere, I Brock, J Chen, T Ferguson, G Tatishvili, H Vogel, ME Watkins, JL Rosner, NE Adam, JP Alexander, K Berkelman, DG Cassel, JE Duboscq, KM Ecklund, R Ehrlich, L Fields, RS Galik, L Gibbons, R Gray, SW Gray, DL Hartill, BK Heltsley, D Hertz, CD Jones, J Kandaswamy, DL Kreinick, VE Kuznetsov, H Mahlke-Krüger, TO Meyer, PUE Onyisi, JR Patterson, D Peterson, J Pivarski, D Riley, A Ryd, AJ Sadoff, H Schwarthoff, X Shi, S Stroiney, WM Sun, T Wilksen, M Weinberger, SB Athar, R Patel, V Potlia, J Yelton, P Rubin, C Cawlfield, BI Eisenstein, I Karliner, D Kim, N Lowrey, P Naik, C Sedlack, M Selen, EJ White, J Wiss, MR Shepherd, CLEO Collaboration

Abstract:

Using data collected with the CLEO III detector at the CESR e+e- collider, we report on a first observation of the decay Upsilon(3S)-->tau+tau-, and precisely measure the ratio of branching fractions of Upsilon(nS), n=1, 2, 3, to tau+tau- and mu+mu- final states, finding agreement with expectations from lepton universality. We derive absolute branching fractions for these decays, and also set a limit on the influence of a low mass CP-odd Higgs boson in the decay of the Upsilon(1S).
More details from the publisher
More details