Measurement of the tt̄ production cross section in pp̄ collisions at s=1.96TeV using secondary vertex b tagging

Physical Review D - Particles, Fields, Gravitation and Cosmology 74:11 (2006)

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, A Askew, BA Asman, 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, I Blackler, G Blazey, F Blekman, S Blessing, D Bloch, K Bloom, U Blumenschein, A Boehnlein, 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, H Castilla-Valdez, S Chakrabarti

Abstract:

We report a new measurement of the tt̄ production cross section in pp̄ collisions at a center-of-mass energy of 1.96 TeV using events with one charged lepton (electron or muon), missing transverse energy, and jets. Using 425pb-1 of data collected using the D0 detector at the Fermilab Tevatron Collider, and enhancing the tt̄ content of the sample by tagging b jets with a secondary vertex tagging algorithm, the tt̄ production cross section is measured to be σpp̄→tt̄+X=6.6±0.9(stat+syst) ±0.4(lum)pb. This cross section is the most precise D0 measurement to date for tt̄ production and is in good agreement with standard model expectations. © 2006 The American Physical Society.

Online system for normalizing data acquired by the Fermilab DØ experiment

Journal of the Korean Physical Society 49:6 (2006) 2247-2252

Authors:

SK Park, J Park, S Lee, SH Ahn, SJ Hong, TJ Kim, KS Lee, M Begel, T Andeen, H Schellman, J Stein, S Yacoob, E Gallas, V Sirotenko, J Hauptman, G Snow

Abstract:

The DØ experiment uses a dedicated data acquisition system to collect, archive, monitor, and distribute the information necessary to normalize triggered data for physics analyses. This system has been in place since the beginning of Run 2 of the Fermilab Tevatron collider in 2001 and provides real-time feedback on the instantaneous and triggered luminosities in the DØ and Tevatron control rooms, as well as the status reports needed for smooth operation of the experiment. This paper describes the architecture and the implementation of this system.

Observation of B(s)0-->K+ K- and measurements of branching fractions of charmless two-body decays of B0 and B(s)0 mesons in pp collisions at square root of s = 1.96 TeV.

Phys Rev Lett 97:21 (2006) 211802

Authors:

A Abulencia, D Acosta, 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, J-F Arguin, T Arisawa, A Artikov, W Ashmanskas, A Attal, F Azfar, P Azzi-Bacchetta, P Azzurri, N Bacchetta, H Bachacou, 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, E Ben Haim, 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, C Bromberg, E Brubaker, J Budagov, HS Budd, S Budd, K Burkett, G Busetto, P Bussey, KL Byrum, S Cabrera, M Campanelli, M Campbell, F Canelli, A Canepa, D Carlsmith, R Carosi, S Carron, M Casarsa, A Castro, P Catastini, D Cauz, M Cavalli-Sforza, A Cerri, L Cerrito, SH Chang, J Chapman, YC Chen, M Chertok, G Chiarelli, G Chlachidze, F Chlebana, I Cho, K Cho, D Chokheli, JP Chou, PH Chu, SH Chuang, K Chung, WH Chung, YS Chung, M Ciljak, CI Ciobanu, MA Ciocci, A Clark, D Clark, M Coca, G Compostella, ME Convery, J Conway, B Cooper, K Copic, M Cordelli, G Cortiana, F Crescioli, A Cruz, C Cuenca Almenar, J Cuevas, R Culbertson, D Cyr, S Daronco, S D'Auria, M D'Onofrio, D Dagenhart, P de Barbaro, S De Cecco, A Deisher, G De Lentdecker, M Dell'Orso, F Delli Paoli, S Demers, L Demortier, J Deng, M Deninno, D De Pedis, PF Derwent, C Dionisi, JR Dittmann, P DiTuro, C Dörr, S Donati, M Donega, P Dong, J Donini, T Dorigo, S Dube, K Ebina, J Efron, J Ehlers, R Erbacher, D Errede, S Errede, R Eusebi, HC Fang, S Farrington, I Fedorko, WT Fedorko, RG Feild, M Feindt, JP Fernandez, R Field, G Flanagan, LR Flores-Castillo, A Foland, S Forrester, GW Foster, M Franklin, JC Freeman, I Furic, M Gallinaro, J Galyardt, JE Garcia, M Garcia Sciveres, AF Garfinkel, C Gay, H Gerberich, D Gerdes, S Giagu, P Giannetti, A Gibson, K Gibson, C Ginsburg, N Giokaris, K Giolo, M Giordani, P Giromini, M Giunta, G Giurgiu, V Glagolev, D Glenzinski, M Gold, N Goldschmidt, J Goldstein, G Gomez, G Gomez-Ceballos, M Goncharov, O González, I Gorelov, AT Goshaw, Y Gotra, K Goulianos, A Gresele, M Griffiths, S Grinstein, C Grosso-Pilcher, U Grundler, J Guimaraes da Costa, Z Gunay-Unalan, C Haber, SR Hahn, K Hahn, E Halkiadakis, A Hamilton, B-Y Han, JY Han, R Handler, F Happacher, K Hara, M Hare, S Harper, RF Harr, RM Harris, K Hatakeyama, J Hauser, C Hays, A Heijboer, B Heinemann, J Heinrich, M Herndon, D Hidas, CS Hill, D Hirschbuehl, A Hocker, A Holloway, S Hou, M Houlden, S-C Hsu, BT Huffman, RE Hughes, J Huston, J Incandela, G Introzzi, M Iori, Y Ishizawa, A Ivanov, B Iyutin, E James, D Jang, B Jayatilaka, D Jeans, H Jensen, EJ Jeon, S Jindariani, M Jones, KK Joo, SY Jun, TR Junk, T Kamon, J Kang, PE Karchin, Y Kato, Y Kemp, R Kephart, U Kerzel, V Khotilovich, B Kilminster, DH Kim, HS Kim, JE Kim, MJ Kim, SB Kim, SH Kim, YK Kim, L Kirsch, S Klimenko, M Klute, B Knuteson, BR Ko, H Kobayashi, K Kondo, DJ Kong, J Konigsberg, A Korytov, AV Kotwal, A Kovalev, A Kraan, J Kraus, I Kravchenko, M Kreps, J Kroll, N Krumnack, M Kruse, V Krutelyov, SE Kuhlmann, Y Kusakabe, S Kwang, AT Laasanen, S Lai, S Lami, S Lammel, M Lancaster, RL Lander, K Lannon, A Lath, G Latino, I Lazzizzera, T LeCompte, J Lee, J Lee, YJ Lee, SW Lee, R Lefèvre, N Leonardo, S Leone, S Levy, JD Lewis, C Lin, CS Lin, M Lindgren, E Lipeles, A Lister, DO Litvintsev, T Liu, NS Lockyer, A Loginov, M Loreti, P Loverre, R-S Lu, D Lucchesi, P Lujan, P Lukens, G Lungu, L Lyons, J Lys, R Lysak, E Lytken, P Mack, D MacQueen, R Madrak, K Maeshima, T Maki, P Maksimovic, S Malde, G Manca, F Margaroli, R Marginean, C Marino, A Martin, V Martin, M Martínez, T Maruyama, P Mastrandrea, H Matsunaga, ME Mattson, R Mazini, P Mazzanti, KS McFarland, P McIntyre, R McNulty, A Mehta, S Menzemer, A Menzione, P Merkel, C Mesropian, A Messina, M von der Mey, T Miao, N Miladinovic, J Miles, R Miller, JS Miller, C Mills, M Milnik, R Miquel, A Mitra, G Mitselmakher, A Miyamoto, N Moggi, B Mohr, R Moore, M Morello, P Movilla Fernandez, J Mülmenstädt, A Mukherjee, Th Muller, R Mumford, P Murat, J Nachtman, J Naganoma, S Nahn, I Nakano, A Napier, D Naumov, V Necula, C Neu, MS Neubauer, J Nielsen, T Nigmanov, L Nodulman, O Norniella, E Nurse, T Ogawa, SH Oh, YD Oh, T Okusawa, R Oldeman, R Orava, K Osterberg, C Pagliarone, E Palencia, R Paoletti, V Papadimitriou, AA Paramonov, B Parks, S Pashapour, J Patrick, G Pauletta, M Paulini, C Paus, DE Pellett, A Penzo, TJ Phillips, G Piacentino, J Piedra, L Pinera, K Pitts, C Plager, L Pondrom, X Portell, O Poukhov, N Pounder, F Prakoshyn, A Pronko, J Proudfoot, F Ptohos, G Punzi, J Pursley, J Rademacker, A Rahaman, A Rakitin, S Rappoccio, F Ratnikov, B Reisert, V Rekovic, N van Remortel, P Renton, M Rescigno, S Richter, F Rimondi, L Ristori, WJ Robertson, A Robson, T Rodrigo, E Rogers, S Rolli, R Roser, M Rossi, R Rossin, C Rott, A Ruiz, J Russ, V Rusu, H Saarikko, S Sabik, A Safonov, WK Sakumoto, G Salamanna, O Saltó, D Saltzberg, C Sanchez, L Santi, S Sarkar, L Sartori, K Sato, P Savard, A Savoy-Navarro, T Scheidle, P Schlabach, EE Schmidt, MP Schmidt, M Schmitt, T Schwarz, L Scodellaro, AL Scott, A Scribano, F Scuri, A Sedov, S Seidel, Y Seiya, A Semenov, L Sexton-Kennedy, I Sfiligoi, MD Shapiro, T Shears, PF Shepard, D Sherman, M Shimojima, M Shochet, Y Shon, I Shreyber, A Sidoti, P Sinervo, A Sisakyan, J Sjolin, A Skiba, AJ Slaughter, K Sliwa, JR Smith, FD Snider, R Snihur, M Soderberg, A Soha, S Somalwar, V Sorin, J Spalding, M Spezziga, F Spinella, T Spreitzer, P Squillacioti, M Stanitzki, A Staveris-Polykalas, R St Denis, B Stelzer, O Stelzer-Chilton, D Stentz, J Strologas, D Stuart, JS Suh, A Sukhanov, K Sumorok, H Sun, T Suzuki, A Taffard, R Takashima, Y Takeuchi, K Takikawa, M Tanaka, R Tanaka, N Tanimoto, M Tecchio, PK Teng, K Terashi, S Tether, J Thom, AS Thompson, E Thomson, P Tipton, V Tiwari, S Tkaczyk, D Toback, S Tokar, K Tollefson, T Tomura, D Tonelli, M Tönnesmann, S Torre, D Torretta, S Tourneur, W Trischuk, R Tsuchiya, S Tsuno, N Turini, F Ukegawa, T Unverhau, S Uozumi, D Usynin, A Vaiciulis, S Vallecorsa, A Varganov, E Vataga, G Velev, G Veramendi, V Veszpremi, R Vidal, I Vila, R Vilar, T Vine, I Vollrath, I Volobouev, G Volpi, F Würthwein, P Wagner, RG Wagner, RL Wagner, W Wagner, R Wallny, T Walter, Z Wan, SM Wang, A Warburton, S Waschke, D Waters, WC Wester, B Whitehouse, D Whiteson, AB Wicklund, E Wicklund, G Williams, HH Williams, P Wilson, BL Winer, P Wittich, S Wolbers, C Wolfe, T Wright, X Wu, SM Wynne, A Yagil, K Yamamoto, J Yamaoka, T Yamashita, C Yang, 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, I Zaw, F Zetti, X Zhang, J Zhou, S Zucchelli, CDF Collaboration

Abstract:

We search for decays of the type B(s)0-->h+ h'- (where h,h' = K or pi) in 180 pb(-1) of pp collisions collected at the Tevatron by the upgraded Collider Detector at Fermilab. We report the first observation of the new mode B(s)0-->K+ K- with a yield of 236+/-32 events, corresponding to (fs/fd) x B(B(s)0-->K+ K-)/B(B0-->K+ pi-) = 0.46+/-0.08stat+/-0.07syst, where fs/fd is the ratio of production fractions of B(s)0 and B0. We find results in agreement with world averages for the B0 modes, and set the following new limits at 90% C.L.: B(B(s)0-->K- pi+) < 5.6 x 10(-6) and B(B(s)0-->pi+ pi-) < 1.7 x 10(-6).

Measurement of the CP-violation parameter of B0 mixing and decay with pp̄→μμX data

Physical Review D - Particles, Fields, Gravitation and Cosmology 74:9 (2006)

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, ACSA 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 measure the dimuon charge asymmetry A in pp̄ collisions at a center of mass energy s=1960GeV. The data was recorded with the D0 detector and corresponds to an integrated luminosity of approximately 1.0fb-1. Assuming that the asymmetry A is due to asymmetric B0↔B̄0 mixing and decay, we extract the CP-violation parameter of B0 mixing and decay: ( B0)1+| B0|2=AB04=-0.0023±0.0011(stat)±0.0008(syst).AB0 is the dimuon charge asymmetry from decays of B0B̄0 pairs. The general case, with CP violation in both B0 and Bs0 systems, is also considered. Finally we obtain the forward-backward asymmetry that quantifies the tendency of μ+ to go in the proton direction and μ- to go in the antiproton direction. The results are consistent with the standard model and constrain new physics. © 2006 The American Physical Society.

Search for pair production of scalar bottom quarks in pp̄ collisions at s=1.96TeV

Physical Review Letters 97:17 (2006)

Authors:

VM Abazov, B Abbott, M Abolins, BS Acharya, M Adams, T Adams, M Agelou, 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, 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, H Castilla-Valdez, D Chakraborty

Abstract:

A search for direct production of scalar bottom quarks (b) is performed with 310pb-1 of data collected by the D0 experiment in pp̄ collisions at s=1.96TeV at the Fermilab Tevatron Collider. The topology analyzed consists of two b jets and an imbalance in transverse momentum due to undetected neutralinos (χ∼10), with χ∼10 assumed to be the lightest supersymmetric particle. We find the data consistent with standard model expectations, and set a 95% C.L. exclusion domain in the (mb∼, mχ∼10) mass plane, improving significantly upon the results from run I of the Tevatron. © 2006 The American Physical Society.