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Search for WW and WZ resonances decaying to electron, missing ET, and two jets in pp̄ collisions at √s=1.96TeV.

Physical Review Letters 104:24 (2010)

Authors:

T Aaltonen, J Adelman, B Álvarez González, S Amerio, D Amidei, A Anastassov, A Annovi, J Antos, G Apollinari, J Appel, A Apresyan, T Arisawa, A Artikov, J Asaadi, W Ashmanskas, A Attal, A Aurisano, F Azfar, W Badgett, A Barbaro-Galtieri, VE Barnes, BA Barnett, P Barria, P Bartos, G Bauer, PH Beauchemin, F Bedeschi, D Beecher, S Behari, G Bellettini, J Bellinger, D Benjamin, A Beretvas, A Bhatti, M Binkley, D Bisello, I Bizjak, RE Blair, C Blocker, B Blumenfeld, A Bocci, A Bodek, V Boisvert, 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, S Camarda, M Campanelli, M Campbell, F Canelli, A Canepa, B Carls, 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, K Chung, WH Chung, YS Chung, T Chwalek, CI Ciobanu, MA Ciocci, A Clark, D Clark, G Compostella, ME Convery, J Conway

Abstract:

Using data from 2.9fb-1 of integrated luminosity collected with the CDF-II detector at the Tevatron, we search for resonances decaying into a pair of on-shell gauge bosons, WW or WZ, where one W decays into an electron and a neutrino, and the other boson decays into two jets. We observed no statistically significant excess above the expected standard model background, and we set cross section limits at 95% confidence level on G* (Randall-Sundrum graviton), Z′, and W′ bosons. By comparing these limits to theoretical cross sections, mass exclusion regions for the three particles are derived. The mass exclusion regions for Z ′ and W′ are further evaluated as a function of their gauge coupling strength. © 2010 The American Physical Society.
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Analysis of D+→K-π+e +νe and D+→K -π+μ++νμ semileptonic decays

Physical Review D - Particles, Fields, Gravitation and Cosmology 81:11 (2010)

Authors:

RA Briere, H Vogel, PUE Onyisi, JL Rosner, JP Alexander, DG Cassel, S Das, R Ehrlich, L Fields, L Gibbons, SW Gray, DL Hartill, BK Heltsley, JM Hunt, DL Kreinick, VE Kuznetsov, J Ledoux, JR Patterson, D Peterson, D Riley, A Ryd, AJ Sadoff, X Shi, WM Sun, J Yelton, P Rubin, N Lowrey, S Mehrabyan, M Selen, J Wiss, M Kornicer, RE Mitchell, MR Shepherd, CM Tarbert, D Besson, TK Pedlar, J Xavier, D Cronin-Hennessy, J Hietala, P Zweber, S Dobbs, Z Metreveli, KK Seth, X Ting, A Tomaradze, S Brisbane, J Libby, L Martin, A Powell, P Spradlin, G Wilkinson, H Mendez, JY Ge, DH Miller, IPJ Shipsey, B Xin, GS Adams, D Hu, B Moziak, J Napolitano, KM Ecklund, J Insler, H Muramatsu, CS Park, EH Thorndike, F Yang, S Ricciardi, C Thomas, M Artuso, S Blusk, S Khalil, R Mountain, T Skwarnicki, S Stone, JC Wang, LM Zhang, G Bonvicini, D Cinabro, A Lincoln, MJ Smith, P Zhou, J Zhu, P Naik, J Rademacker, DM Asner, KW Edwards, J Reed, K Randrianarivony, AN Robichaud, G Tatishvili, EJ White

Abstract:

Using a large sample (≈11800 events) of D+→K -π+e+νe and D+→K -π+μ+νμ decays collected by the CLEO-c detector running at the ψ(3770), we measure the helicity basis form factors free from the assumptions of spectroscopic pole dominance and provide new, accurate measurements of the absolute branching fractions for D +→K̄*0e+νe and D+→K̄*0μ+νμ decays. We find branching fractions which are consistent with previous world averages. Our measured helicity basis form factors are consistent with the spectroscopic pole dominance predictions for the three main helicity basis form factors describing D+→K̄*0 +ν decay. The ability to analyze D+→K -π+μ+νμ allows us to make the first nonparametric measurements of the mass-suppressed form factor. Our result is inconsistent with existing lattice QCD calculations. Finally, we measure the form factor that controls nonresonant s-wave interference with the D +→K̄*0+ν amplitude and search for evidence of possible additional nonresonant d- or f-wave interference with the K̄*0. © 2010 The American Physical Society.
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First spatial alignment of the LHCb VELO and analysis of beam absorber collision data

Nuclear Instruments and Methods in Physics Research Section A Accelerators Spectrometers Detectors and Associated Equipment Elsevier 618:1-3 (2010) 108-120

Authors:

S Borghi, M Gersabeck, C Parkes, T Szumlak, A Affolder, K Akiba, J Anderson, M Artuso, S Basiladze, A Bates, A Bay, O Behrendt, M van Beuzekom, A Borgia, T Bowcock, J Buytaert, G Casse, P Collins, S de Capua, H de Vries, S Donleavy, L Eklund, M Ferro-Luzzi, R Frei, K Hennessy, T Huse, D Hutchcroft, E Jans, M John, T Ketel, G Lefeuvre, A Leflat, F Marinho, R McNulty, R Mountain, I Mous, J Mylroie-Smith, A Noor, A Papadelis, G Patel, B Rakotomiaramanana, K Rinnert, E Rodrigues, T Shears, NA Smith, M Tobin, S Traynor, A Van Lysebetten, B Verlaat, J Wang
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Branching fractions for chi_cJ -> p p-bar pi^0, p p-bar eta, and p p-bar omega

(2010)

Authors:

CLEO Collaboration, PUE Onyisi, JL Rosner, JP Alexander, DG Cassel, S Das, R Ehrlich, L Fields, L Gibbons, SW Gray, DL Hartill, BK Heltsley, JM Hunt, DL Kreinick, VE Kuznetsov, J Ledoux, JR Patterson, D Peterson, D Riley, A Ryd, AJ Sadoff, X Shi, WM Sun, J Yelton, P Rubin, N Lowrey, S Mehrabyan, M Selen, J Wiss, S Adams, M Kornicer, RE Mitchell, MR Shepherd, CM Tarbert, D Besson, TK Pedlar, J Xavier, D Cronin-Hennessy, J Hietala, P Zweber, S Dobbs, Z Metreveli, KK Seth, T Xiao, A Tomaradze, S Brisbane, J Libby, L Martin, A Powell, P Spradlin, G Wilkinson, H Mendez, JY Ge, DH Miller, IPJ Shipsey, B Xin, GS Adams, D Hu, B Moziak, J Napolitano, KM Ecklund, J Insler, H Muramatsu, CS Park, EH Thorndike, F Yang, S Ricciardi, C Thomas, M Artuso, S Blusk, R Mountain, T Skwarnicki, S Stone, JC Wang, LM Zhang, G Bonvicini, D Cinabro, A Lincoln, MJ Smith, P Zhou, J Zhu, P Naik, J Rademacker, DM Asner, KW Edwards, J Reed, K Randrianarivony, AN Robichaud, G Tatishvili, EJ White, RA Briere, H Vogel
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Search for the decay J/ψ→γ+invisible

Physical Review D - Particles, Fields, Gravitation and Cosmology 81:9 (2010)

Authors:

J Insler, H Muramatsu, CS Park, EH Thorndike, F Yang, S Ricciardi, C Thomas, M Artuso, S Blusk, S Khalil, R Mountain, T Skwarnicki, S Stone, JC Wang, LM Zhang, G Bonvicini, D Cinabro, A Lincoln, MJ Smith, P Zhou, J Zhu, P Naik, J Rademacker, DM Asner, KW Edwards, K Randrianarivony, J Reed, AN Robichaud, G Tatishvili, EJ White, RA Briere, H Vogel, PUE Onyisi, JL Rosner, JP Alexander, DG Cassel, R Ehrlich, L Fields, L Gibbons, SW Gray, DL Hartill, BK Heltsley, JM Hunt, DL Kreinick, VE Kuznetsov, J Ledoux, H Mahlke-Krüger, JR Patterson, D Peterson, D Riley, A Ryd, AJ Sadoff, X Shi, S Stroiney, WM Sun, J Yelton, P Rubin, N Lowrey, S Mehrabyan, M Selen, J Wiss, M Kornicer, RE Mitchell, MR Shepherd, CM Tarbert, D Besson, TK Pedlar, J Xavier, D Cronin-Hennessy, KY Gao, J Hietala, R Poling, P Zweber, S Dobbs, Z Metreveli, KK Seth, X Ting, A Tomaradze, S Brisbane, J Libby, L Martin, A Powell, P Spradlin, G Wilkinson, H Mendez, JY Ge, DH Miller, IPJ Shipsey, B Xin, GS Adams, D Hu, B Moziak, J Napolitano, KM Ecklund

Abstract:

A search for J/ψ radiative decay to weakly interacting neutral final states was performed using the CLEO-c detector at the Cornell Electron Storage Ring. J/ψ events were selected by observing the hadronic decay ψ(2S)→π+π-J/ψ. A total of 3.7×106 J/ψ events were used to study the decay J/ψ→γ+X, where X is a narrow state that is invisible to the detector. No significant signal was observed, and upper limits on the branching fraction were set for masses mX up to 960MeV/c2. The upper limit corresponding to mX=0 is 4.3×10-6 at the 90% confidence level. © 2010 The American Physical Society.
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