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Measurement of the tt̄ cross section in pp̄ collisions at s=1.96TeV using dilepton events with a lepton plus track selection

Physical Review D - Particles, Fields, Gravitation and Cosmology 79:11 (2009)

Authors:

T Aaltonen, J Adelman, T Akimoto, BA 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, W Badgett, A Barbaro-Galtieri, VE Barnes, BA Barnett, P Barria, V Bartsch, G Bauer, PH Beauchemin, F Bedeschi, 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, S Burke, K Burkett, G Busetto, P Bussey, A Buzatu, KL Byrum, S Cabrera, C Calancha, 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, G Choudalakis, SH Chuang, K Chung, WH Chung, YS Chung, T Chwalek, CI Ciobanu, MA Ciocci, A Clark, D Clark

Abstract:

This paper reports a measurement of the cross section for the pair production of top quarks in pp̄ collisions at s=1.96TeV at the Fermilab Tevatron. The data were collected from the CDF run II detector in a set of runs with a total integrated luminosity of 1.1fb-1. The cross section is measured in the dilepton channel, the subset of tt̄ events in which both top quarks decay through t→Wb→ νb, where =e, μ, or τ. The lepton pair is reconstructed as one identified electron or muon and one isolated track. The use of an isolated track to identify the second lepton increases the tt̄ acceptance, particularly for the case in which one W decays as W→τν. The purity of the sample may be further improved at the cost of a reduction in the number of signal events, by requiring an identified b jet. We present the results of measurements performed with and without the request of an identified b jet. The former is the first published CDF result for which a b-jet requirement is added to the dilepton selection. In the CDF data there are 129 pretag lepton+track candidate events, of which 69 are tagged. With the tagging information, the sample is divided into tagged and untagged subsamples, and a combined cross section is calculated by maximizing a likelihood. The result is σtt̄=9.6±1.2(stat)-0.5+0.6(sys)±0.6(lum)pb, assuming a branching ratio of BR(W→ ν)=10.8% and a top mass of mt=175GeV/c2. © 2009 The American Physical Society.
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Measurement of the ratio of branching fractions B(B±→J/ ψπ±)/B(B±→J/ψK±)

Physical Review D - Particles, Fields, Gravitation and Cosmology 79:11 (2009)

Authors:

A Abulencia, 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, JF Arguin, T Arisawa, A Artikov, W Ashmanskas, A Attal, F Azfar, P Azzi-Bacchetta, P Azzurri, N Bacchetta, W Badgett, A Barbaro-Galtieri, VE Barnes, BA Barnett, S Baroiant, V Bartsch, G Bauer, F Bedeschi, S Behari, S Belforte, G Bellettini, J Bellinger, A Belloni, D Benjamin, A Beretvas, J Beringer, T Berry, A Bhatti, M Binkley, D Bisello, RE Blair, C Blocker, B Blumenfeld, A Bocci, A Bodek, V Boisvert, G Bolla, A Bolshov, D Bortoletto, J Boudreau, A Boveia, B Brau, L Brigliadori, C Bromberg, E Brubaker, J Budagov, HS Budd, S Budd, S Budroni, K Burkett, G Busetto, P Bussey, KL Byrum, S Cabrera, M Campanelli, M Campbell, F Canelli, A Canepa, S Carillo, D Carlsmith, R Carosi, S Carron, M Casarsa, A Castro, P Catastini, D Cauz, M Cavalli-Sforza, A Cerri, L Cerrito, SH Chang, YC Chen, M Chertok, G Chiarelli, G Chlachidze, F Chlebana, I Cho, K Cho, D Chokheli, JP Chou, G Choudalakis, SH Chuang, K Chung, WH Chung, YS Chung, M Ciljak, CI Ciobanu, MA Ciocci

Abstract:

We report a measurement of the ratio of branching fractions of the decays B±→J/ψπ± and B±→J/ψK± using the CDF II detector at the Fermilab Tevatron Collider. The signal from the Cabbibo-suppressed B±→J/ψπ± decay is separated from B±→J/ψK± using the B±→J/ψK± invariant mass distribution and the kinematical differences of the hadron track in the two decay modes. From a sample of 220pb-1 of pp̄ collisions at s=1.96TeV, we observe 91±15 B±→J/ψπ± events together with 1883±34 B±→J/ψK± events. The ratio of branching fractions is found to be B(B±→J/ψπ±)/ B(B±→J/ψK±)=(4.86±0.82(stat)±0.15(syst))%. © 2009 The American Physical Society.
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Charmonium decays to γπ0, γη, and γη′

Physical Review D - Particles, Fields, Gravitation and Cosmology 79:11 (2009)

Authors:

TK Pedlar, J Xavier, D Cronin-Hennessy, KY Gao, J Hietala, T Klein, R Poling, P Zweber, S Dobbs, Z Metreveli, KK Seth, BJY Tan, A Tomaradze, J Libby, L Martin, A Powell, C Thomas, G Wilkinson, H Mendez, JY Ge, DH Miller, IPJ Shipsey, B Xin, GS Adams, D Hu, B Moziak, J Napolitano, KM Ecklund, Q He, J Insler, H Muramatsu, CS Park, EH Thorndike, F Yang, M Artuso, S Blusk, S Khalil, R Mountain, K Randrianarivony, T Skwarnicki, S Stone, JC Wang, LM Zhang, G Bonvicini, D Cinabro, M Dubrovin, A Lincoln, MJ Smith, P Zhou, J Zhu, P Naik, J Rademacker, DM Asner, KW Edwards, J Reed, AN Robichaud, G Tatishvili, EJ White, RA Briere, H Vogel, PUE Onyisi, JL Rosner, JP Alexander, DG Cassel, R Ehrlich, L Fields, RS Galik, L Gibbons, R Gray, SW Gray, DL Hartill, BK Heltsley, D Hertz, JM Hunt, J Kandaswamy, 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, T Wilksen, J Yelton, P Rubin, N Lowrey, S Mehrabyan, M Selen, J Wiss, M Kornicer, RE Mitchell, MR Shepherd, C Tarbert, D Besson

Abstract:

Using data acquired with the CLEO-c detector at the CESR e+e- collider, we measure branching fractions for J/ψ, ψ(2S), and ψ(3770) decays to γπ0, γη, and γη′. Defining Rn B[ψ(nS)→γη]/B[ψ(nS)→γη′], we obtain R1=(21.1±0.9)% and, unexpectedly, an order of magnitude smaller limit, R2<1.8% at 90% C.L. We also use J/ψ→γη′ events to determine branching fractions of improved precision for the five most copious η′ decay modes. © 2009 The American Physical Society.
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First measurement of the tt̄ differential cross section dσ/dMtt̄ in pp̄ collisions at s=1.96TeV

Physical Review Letters 102:22 (2009)

Authors:

T Aaltonen, J Adelman, T Akimoto, 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, 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, S Burke, K Burkett, G Busetto, P Bussey, A Buzatu, KL Byrum, S Cabrera, C Calancha, 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, G Choudalakis, SH Chuang, K Chung, WH Chung, YS Chung, T Chwalek, CI Ciobanu, MA Ciocci, A Clark, D Clark

Abstract:

We present a measurement of the tt̄ differential cross section with respect to the tt̄ invariant mass, dσ/dMtt̄, in pp̄ collisions at s=1.96TeV using an integrated luminosity of 2.7fb-1 collected by the CDF II experiment. The tt̄ invariant mass spectrum is sensitive to a variety of exotic particles decaying into tt̄ pairs. The result is consistent with the standard model expectation, as modeled by PYTHIA with CTEQ5L parton distribution functions. © 2009 The American Physical Society.
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First measurement of the tt[over ] differential cross section dsigma/dM_{tt[over ]} in pp[over ] collisions at sqrt[s]=1.96 TeV.

Phys Rev Lett 102:22 (2009) 222003

Authors:

T Aaltonen, J Adelman, T Akimoto, B Alvarez 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, P-H Beauchemin, F Bedeschi, 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, S Burke, K Burkett, G Busetto, P Bussey, A Buzatu, KL Byrum, S Cabrera, C Calancha, 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, G Choudalakis, SH Chuang, K Chung, WH Chung, YS Chung, T Chwalek, CI Ciobanu, MA Ciocci, A Clark, D Clark, G Compostella, ME Convery, J Conway, M Cordelli, G Cortiana, CA Cox, DJ Cox, F Crescioli, C Cuenca Almenar, J Cuevas, R Culbertson, JC Cully, D Dagenhart, M Datta, T Davies, P de Barbaro, S De Cecco, A Deisher, G De Lorenzo, M Dell'orso, C Deluca, L Demortier, J Deng, M Deninno, PF Derwent, GP di Giovanni, C Dionisi, B Di Ruzza, JR Dittmann, M D'Onofrio, S Donati, P Dong, J Donini, T Dorigo, S Dube, J Efron, A Elagin, R Erbacher, D Errede, S Errede, R Eusebi, HC Fang, S Farrington, WT Fedorko, RG Feild, M Feindt, JP Fernandez, C Ferrazza, R Field, G Flanagan, R Forrest, MJ Frank, M Franklin, JC Freeman, I Furic, M Gallinaro, J Galyardt, F Garberson, JE Garcia, AF Garfinkel, K Genser, H Gerberich, D Gerdes, A Gessler, S Giagu, V Giakoumopoulou, P Giannetti, K Gibson, JL Gimmell, CM Ginsburg, N Giokaris, M Giordani, P Giromini, M Giunta, G Giurgiu, V Glagolev, D Glenzinski, M Gold, N Goldschmidt, A Golossanov, G Gomez, G Gomez-Ceballos, M Goncharov, O González, I Gorelov, AT Goshaw, K Goulianos, A Gresele, S Grinstein, C Grosso-Pilcher, U Grundler, J Guimaraes da Costa, Z Gunay-Unalan, C Haber, K Hahn, SR Hahn, E Halkiadakis, B-Y Han, JY Han, F Happacher, K Hara, D Hare, M Hare, S Harper, RF Harr, RM Harris, M Hartz, K Hatakeyama, C Hays, M Heck, A Heijboer, J Heinrich, C Henderson, M Herndon, J Heuser, S Hewamanage, D Hidas, CS Hill, D Hirschbuehl, A Hocker, S Hou, M Houlden, S-C Hsu, BT Huffman, RE Hughes, U Husemann, M Hussein, J Huston, J Incandela, G Introzzi, M Iori, A Ivanov, E James, D Jang, B Jayatilaka, EJ Jeon, MK Jha, S Jindariani, W Johnson, M Jones, KK Joo, SY Jun, JE Jung, TR Junk, T Kamon, D Kar, PE Karchin, Y Kato, R Kephart, J Keung, V Khotilovich, B Kilminster, DH Kim, HS Kim, HW Kim, JE Kim, MJ Kim, SB Kim, SH Kim, YK Kim, N Kimura, L Kirsch, S Klimenko, B Knuteson, BR Ko, K Kondo, DJ Kong, J Konigsberg, A Korytov, AV Kotwal, M Kreps, J Kroll, D Krop, N Krumnack, M Kruse, V Krutelyov, T Kubo, T Kuhr, NP Kulkarni, M Kurata, S Kwang, AT Laasanen, S Lami, S Lammel, M Lancaster, RL Lander, K Lannon, A Lath, G Latino, I Lazzizzera, T Lecompte, E Lee, HS Lee, SW Lee, S Leone, JD Lewis, C-S Lin, J Linacre, M Lindgren, E Lipeles, TM Liss, A Lister, DO Litvintsev, C Liu, T Liu, NS Lockyer, A Loginov, M Loreti, L Lovas, D Lucchesi, C Luci, J Lueck, P Lujan, P Lukens, G Lungu, L Lyons, J Lys, R Lysak, D Macqueen, R Madrak, K Maeshima, K Makhoul, T Maki, P Maksimovic, S Malde, S Malik, G Manca, A Manousakis-Katsikakis, F Margaroli, C Marino, CP Marino, A Martin, V Martin, M Martínez, R Martínez-Ballarín, T Maruyama, P Mastrandrea, T Masubuchi, M Mathis, ME Mattson, P Mazzanti, KS McFarland, P McIntyre, R McNulty, A Mehta, P Mehtala, A Menzione, P Merkel, C Mesropian, T Miao, N Miladinovic, R Miller, C Mills, M Milnik, A Mitra, G Mitselmakher, H Miyake, N Moggi, CS Moon, R Moore, MJ Morello, J Morlock, P Movilla Fernandez, J Mülmenstädt, A Mukherjee, Th Muller, R Mumford, P Murat, M Mussini, J Nachtman, Y Nagai, A Nagano, J Naganoma, K Nakamura, I Nakano, A Napier, V Necula, J Nett, C Neu, MS Neubauer, S Neubauer, J Nielsen, L Nodulman, M Norman, O Norniella, E Nurse, L Oakes, SH Oh, YD Oh, I Oksuzian, T Okusawa, R Orava, K Osterberg, S Pagan Griso, E Palencia, V Papadimitriou, A Papaikonomou, AA Paramonov, B Parks, S Pashapour, J Patrick, G Pauletta, M Paulini, C Paus, T Peiffer, DE Pellett, A Penzo, TJ Phillips, G Piacentino, E Pianori, L Pinera, K Pitts, C Plager, L Pondrom, O Poukhov, N Pounder, F Prakoshyn, A Pronko, J Proudfoot, F Ptohos, E Pueschel, G Punzi, J Pursley, J Rademacker, A Rahaman, V Ramakrishnan, N Ranjan, I Redondo, P Renton, M Renz, M Rescigno, S Richter, F Rimondi, L Ristori, A Robson, T Rodrigo, T Rodriguez, E Rogers, S Rolli, R Roser, M Rossi, R Rossin, P Roy, A Ruiz, J Russ, V Rusu, B Rutherford, H Saarikko, A Safonov, WK Sakumoto, O Saltó, L Santi, S Sarkar, L Sartori, K Sato, A Savoy-Navarro, P Schlabach, A Schmidt, EE Schmidt, MA Schmidt, MP Schmidt, M Schmitt, T Schwarz, L Scodellaro, A Scribano, F Scuri, A Sedov, S Seidel, Y Seiya, A Semenov, L Sexton-Kennedy, F Sforza, A Sfyrla, SZ Shalhout, T Shears, PF Shepard, M Shimojima, S Shiraishi, M Shochet, Y Shon, I Shreyber, A Sidoti, P Sinervo, A Sisakyan, AJ Slaughter, J Slaunwhite, K Sliwa, JR Smith, FD Snider, R Snihur, A Soha, S Somalwar, V Sorin, J Spalding, T Spreitzer, P Squillacioti, M Stanitzki, R St Denis, B Stelzer, O Stelzer-Chilton, D Stentz, J Strologas, GL Strycker, D Stuart, JS Suh, A Sukhanov, I Suslov, T Suzuki, A Taffard, R Takashima, Y Takeuchi, R Tanaka, M Tecchio, PK Teng, K Terashi, J Thom, AS Thompson, GA Thompson, E Thomson, P Tipton, P Ttito-Guzmán, S Tkaczyk, D Toback, S Tokar, K Tollefson, T Tomura, D Tonelli, S Torre, D Torretta, P Totaro, S Tourneur, M Trovato, S-Y Tsai, Y Tu, N Turini, F Ukegawa, S Vallecorsa, N van Remortel, A Varganov, E Vataga, F Vázquez, G Velev, C Vellidis, M Vidal, R Vidal, I Vila, R Vilar, T Vine, M Vogel, I Volobouev, G Volpi, P Wagner, RG Wagner, RL Wagner, W Wagner, J Wagner-Kuhr, T Wakisaka, R Wallny, SM Wang, A Warburton, D Waters, M Weinberger, J Weinelt, WC Wester, B Whitehouse, D Whiteson, AB Wicklund, E Wicklund, S Wilbur, G Williams, HH Williams, P Wilson, BL Winer, P Wittich, S Wolbers, C Wolfe, T Wright, X Wu, F Würthwein, S Xie, A Yagil, K Yamamoto, J Yamaoka, UK Yang, YC Yang, WM Yao, GP Yeh, J Yoh, K Yorita, T Yoshida, GB Yu, I Yu, SS Yu, JC Yun, L Zanello, A Zanetti, X Zhang, Y Zheng, S Zucchelli, CDF Collaboration

Abstract:

We present a measurement of the tt[over ] differential cross section with respect to the tt[over ] invariant mass, dsigma/dM_{tt[over ]}, in pp[over ] collisions at sqrt[s]=1.96 TeV using an integrated luminosity of 2.7 fb;{-1} collected by the CDF II experiment. The tt[over ] invariant mass spectrum is sensitive to a variety of exotic particles decaying into tt[over ] pairs. The result is consistent with the standard model expectation, as modeled by PYTHIA with CTEQ5L parton distribution functions.
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