Search for anomalous kinematics in tt̄ dilepton events at CDF II

Physical Review Letters 95:2 (2005)

Authors:

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, T Arisawa, JF Arguin, A Artikov, W Ashmanskas, A Attal, F Azfar, P Azzi-Bacchetta, N Bacchetta, H Bachacou, W Badgett, A Barbaro-Galtieri, GJ Barker, VE Barnes, BA Barnett, S Baroiant, M Barone, G Bauer, F Bedeschi, S Behari, S Belforte, G Bellettini, J Bellinger, E Ben-Haim, D Benjamin, A Beretvas, A Bhatti, M Binkley, D Bisello, M Bishai, RE Blair, C Blocker, K Bloom, B Blumenfeld, A Bocci, A Bodek, G Bolla, A Bolshov, PSL Booth, D Bortoletto, J Boudreau, S Bourov, B Brau, C Bromberg, E Brubaker, J Budagov, HS Budd, K Burkett, G Busetto, P Bussey, KL Byrum, S Cabrera, M Campanelli, M Campbell, A Canepa, M Casarsa, D Carlsmith, S Carron, R Carosi, M Cavalli-Sforza, A Castro, P Catastini, D Cauz, A Cerri, L Cerrito, J Chapman, C Chen, YC Chen, M Chertok, G Chiarelli, G Chlachidze, F Chlebana, I Cho, K Cho, D Chokheli, JP Chou, ML Chu, S Chuang, JY Chung, WH Chung, YS Chung, CI Ciobanu, MA Ciocci, AG Clark, D Clark, M Coca, A Connolly

Abstract:

We report on a search for anomalous kinematics of tt̄ dilepton events in pp̄ collisions at s=1.96TeV using 193pb-1 of data collected with the CDF II detector. We developed a new a priori technique designed to isolate the subset in a data sample revealing the largest deviation from standard model (SM) expectations and to quantify the significance of this departure. In the four-variable space considered, no particular subset shows a significant discrepancy, and we find that the probability of obtaining a data sample less consistent with the SM than what is observed is 1.0%-4.5%. © 2005 The American Physical Society.

Search for anomalous kinematics in tt dilepton events at CDF II.

Phys Rev Lett 95:2 (2005) 022001

Authors:

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, T Arisawa, J-F Arguin, A Artikov, W Ashmanskas, A Attal, F Azfar, P Azzi-Bacchetta, N Bacchetta, H Bachacou, W Badgett, A Barbaro-Galtieri, GJ Barker, VE Barnes, BA Barnett, S Baroiant, M Barone, G Bauer, F Bedeschi, S Behari, S Belforte, G Bellettini, J Bellinger, E Ben-Haim, D Benjamin, A Beretvas, A Bhatti, M Binkley, D Bisello, M Bishai, RE Blair, C Blocker, K Bloom, B Blumenfeld, A Bocci, A Bodek, G Bolla, A Bolshov, PSL Booth, D Bortoletto, J Boudreau, S Bourov, B Brau, C Bromberg, E Brubaker, J Budagov, HS Budd, K Burkett, G Busetto, P Bussey, KL Byrum, S Cabrera, M Campanelli, M Campbell, A Canepa, M Casarsa, D Carlsmith, S Carron, R Carosi, M Cavalli-Sforza, A Castro, P Catastini, D Cauz, A Cerri, L Cerrito, J Chapman, C Chen, YC Chen, M Chertok, G Chiarelli, G Chlachidze, F Chlebana, I Cho, K Cho, D Chokheli, JP Chou, ML Chu, S Chuang, JY Chung, W-H Chung, YS Chung, CI Ciobanu, MA Ciocci, AG Clark, D Clark, M Coca, A Connolly, M Convery, J Conway, B Cooper, M Cordelli, G Cortiana, J Cranshaw, J Cuevas, R Culbertson, C Currat, D Cyr, D Dagenhart, S Da Ronco, S D'Auria, P de Barbaro, S De Cecco, G De Lentdecker, S Dell'Agnello, M Dell'Orso, S Demers, L Demortier, M Deninno, D De Pedis, PF Derwent, C Dionisi, JR Dittmann, C Dörr, P Doksus, A Dominguez, S Donati, M Donega, J Donini, M D'Onofrio, T Dorigo, V Drollinger, K Ebina, N Eddy, J Ehlers, R Ely, R Erbacher, M Erdmann, D Errede, S Errede, R Eusebi, H-C Fang, S Farrington, I Fedorko, WT Fedorko, RG Feild, M Feindt, JP Fernandez, C Ferretti, RD Field, G Flanagan, B Flaugher, LR Flores-Castillo, A Foland, S Forrester, GW Foster, M Franklin, JC Freeman, Y Fujii, I Furic, A Gajjar, A Gallas, J Galyardt, M Gallinaro, M Garcia-Sciveres, AF Garfinkel, C Gay, H Gerberich, DW Gerdes, E Gerchtein, S Giagu, P Giannetti, A Gibson, K Gibson, C Ginsburg, K Giolo, M Giordani, M Giunta, G Giurgiu, V Glagolev, D Glenzinski, M Gold, N Goldschmidt, D Goldstein, J Goldstein, G Gomez, G Gomez-Ceballos, M Goncharov, O González, I Gorelov, AT Goshaw, Y Gotra, K Goulianos, A Gresele, M Griffiths, C Grosso-Pilcher, U Grundler, M Guenther, J Guimaraes da Costa, C Haber, K Hahn, SR Hahn, E Halkiadakis, A Hamilton, B-Y Han, R Handler, F Happacher, K Hara, M Hare, RF Harr, RM Harris, F Hartmann, K Hatakeyama, J Hauser, C Hays, H Hayward, E Heider, B Heinemann, J Heinrich, M Hennecke, M Herndon, C Hill, D Hirschhbuehl, A Hocker, KD Hoffman, A Holloway, S Hou, MA Houlden, BT Huffman, Y Huang, RE Hughes, J Huston, K Ikado, J Incandela, G Introzzi, M Iori, Y Ishizawa, C Issever, A Ivanov, Y Iwata, B Iyutin, E James, D Jang, J Jarrell, D Jeans, H Jensen, EJ Jeon, M Jones, KK Joo, SY Jun, T Junk, T Kamon, J Kang, M Karagoz Unel, PE Karchin, S Kartal, Y Kato, Y Kemp, R Kephart, U Kerzel, V Khotilovich, B Kilminster, DH Kim, HS Kim, JE Kim, MJ Kim, MS Kim, SB Kim, SH Kim, TH Kim, YK Kim, BT King, M Kirby, L Kirsch, S Klimenko, B Knuteson, BR Ko, H Kobayashi, P Koehn, DJ Kong, K Kondo, J Konigsberg, K Kordas, A Korn, A Korytov, K Kotelnikov, AV Kotwal, A Kovalev, J Kraus, I Kravchenko, A Kreymer, J Kroll, M Kruse, V Krutelyov, SE Kuhlmann, S Kwang, AT Laasanen, S Lai, S Lami, S Lammel, J Lancaster, M Lancaster, R Lander, K Lannon, A Lath, G Latino, R Lauhakangas, I Lazzizzera, Y Le, C Lecci, T LeCompte, J Lee, J Lee, SW Lee, R Lefèvre, N Leonardo, S Leone, S Levy, JD Lewis, K Li, C Lin, CS Lin, M Lindgren, TM Liss, A Lister, DO Litvintsev, T Liu, Y 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, D MacQueen, R Madrak, K Maeshima, P Maksimovic, L Malferrari, G Manca, R Marginean, C Marino, A Martin, M Martin, V Martin, M Martínez, T Maruyama, H Matsunaga, M Mattson, P Mazzanti, KS McFarland, D McGivern, PM McIntyre, P McNamara, R NcNulty, A Mehta, S Menzemer, A Menzione, P Merkel, C Mesropian, A Messina, T Miao, N Miladinovic, L Miller, R Miller, JS Miller, R Miquel, S Miscetti, G Mitselmakher, A Miyamoto, Y Miyazaki, N Moggi, B Mohr, R Moore, M Morello, PA Movilla Fernandez, A Mukherjee, M Mulhearn, T Muller, R Mumford, A Munar, P Murat, J Nachtman, S Nahn, I Nakamura, I Nakano, A Napier, R Napora, D Naumov, V Necula, F Niell, J Nielsen, C Nelson, T Nelson, C Neu, MS Neubauer, C Newman-Holmes, T Nigmanov, L Nodulman, O Norniella, K Oesterberg, T Ogawa, SH Oh, YD Oh, T Ohsugi, T Okusawa, R Oldeman, R Orava, W Orejudos, C Pagliarone, E Palencia, R Paoletti, V Papadimitriou, S Pashapour, J Patrick, G Pauletta, M Paulini, T Pauly, C Paus, D Pellett, A Penzo, TJ Phillips, G Piacentino, J Piedra, KT Pitts, C Plager, A Pompos, L Pondrom, G Pope, X Portell, O Poukhov, F Prakoshyn, T Pratt, A Pronko, J Proudfoot, F Ptohos, G Punzi, J Rademachker, MA Rahaman, A Rakitine, S Rappoccio, F Ratnikov, H Ray, B Reisert, V Rekovic, P Renton, M Rescigno, F Rimondi, K Rinnert, L Ristori, WJ Robertson, A Robson, T Rodrigo, S Rolli, L Rosenson, R Roser, R Rossin, C Rott, J Russ, V Rusu, A Ruiz, D Ryan, H Saarikko, S Sabik, A Safonov, R St Denis, WK Sakumoto, G Salamanna, D Saltzberg, C Sanchez, A Sansoni, L Santi, S Sarkar, K Sato, P Savard, A Savoy-Navarro, P Schlabach, EE Schmidt, MP Schmidt, M Schmitt, L Scodellaro, A Scribano, F Scuri, A Sedov, S Seidel, Y Seiya, F Semeria, L Sexton-Kennedy, I Sfiligoi, MD Shapiro, T Shears, PF Shepard, D Sherman, M Shimojima, M Shochet, Y Shon, I Shreyber, A Sidoti, J Siegrist, M Siket, A Sill, P Sinervo, A Sisakyan, A Skiba, AJ Slaughter, K Sliwa, D Smirnov, JR Smith, FD Snider, R Snihur, A Soha, SV Somalwar, J Spalding, M Spezziga, L Spiegel, F Spinella, M Spiropulu, P Squillacioti, H Stadie, B Stelzer, O Stelzer-Chilton, J Strologas, D Stuart, A Sukhanov, K Sumorok, H Sun, T Suzuki, A Taffard, R Tafirout, SF Takach, H Takano, R Takashima, Y Takeuchi, K Takikawa, M Tanaka, R Tanaka, N Tanimoto, S Tapprogge, M Tecchio, PK Teng, K Terashi, RJ Tesarek, S Tether, J Thom, AS Thompson, E Thomson, P Tipton, V Tiwari, S Trkaczyk, D Toback, K Tollefson, T Tomura, D Tonelli, M Tönnesmann, S Torre, D Torretta, S Tourneur, W Trischuk, J Tseng, R Tsuchiya, S Tsuno, D Tsybychev, N Turini, M Turner, F Ukegawa, T Unverhau, S Uozumi, D Usynin, L Vacavant, A Vaiciulis, A Varganov, E Vataga, S Vejcik, G Velev, V Veszpremi, G Veramendi, T Vickey, R Vidal, I Vila, R Vilar, I Vollrath, I Volobouev, M von der Mey, P Wagner, RG Wagner, RL Wagner, W Wagner, R Wallny, T Walter, T Yamashita, K Yamamoto, Z Wan, MJ Wang, SM Wang, A Warburton, B Ward, S Waschke, D Waters, T Watts, M Weber, WC Wester, B Whitehouse, AB Wicklund, E Wicklund, HH Williams, P Wilson, BL Winer, P Wittich, S Wolbers, M Wolter, M Worcester, S Worm, T Wright, X Wu, F Würthwein, A Wyatt, A Yagil, C Yang, UK Yang, W Yao, GP Yeh, K Yi, J Yoh, P Yoon, K Yorita, T Yoshida, I Yu, S Yu, Z Yu, JC Yun, L Zanello, A Zanetti, I Zaw, F Zetti, J Zhou, A Zsenei, S Zucchelli, CDF Collaboration

Abstract:

We report on a search for anomalous kinematics of tt dilepton events in pp collisions at square root of s=1.96 TeV using 193 pb(-1) of data collected with the CDF II detector. We developed a new a priori technique designed to isolate the subset in a data sample revealing the largest deviation from standard model (SM) expectations and to quantify the significance of this departure. In the four-variable space considered, no particular subset shows a significant discrepancy, and we find that the probability of obtaining a data sample less consistent with the SM than what is observed is 1.0%-4.5%.

Impact of future HERA data on the determination of proton parton distribution functions using the ZEUS QCD fit

(2005)

An NLO QCD analysis of inclusive cross-section and jet-production data from the ZEUS experiment

European Physical Journal C 42:1 (2005) 1-16

Authors:

S Chekanov, M Derrick, S Magill, S Miglioranzi, B Musgrave, J Repond, R Yoshida, MCK Mattingly, N Pavel, AG Yagües Molina, P Antonioli, G Bari, M Basile, L Bellagamba, D Boscherini, A Bruni, G Bruni, G Cara Romeo, L Cifarelli, F Cindolo, A Contin, M Corradi, S de Pasquale, P Giusti, G Iacobucci, A Margotti, A Montanari, R Nania, F Palmonari, A Pesci, A Polini, L Rinaldi, G Sartorelli, A Zichichi, G Aghuzumtsyan, D Bartsch, I Brock, S Goers, H Hartmann, E Hilger, P Irrgang, HP Jakob, OM Kind, U Meyer, E Paul, J Rautenberg, R Renner, KC Voss, M Wang, M Wlasenko, DS Bailey, NH Brook, JE Cole, GP Heath, T Namsoo, S Robins, M Capua, S Fazio, A Mastroberardino, M Schioppa, G Susinno, E Tassi, JY Kim, KJ Ma, M Helbich, Y Ning, Z Ren, WB Schmidke, F Sciulli, J Chwastowski, A Eskreys, J Figiel, A Galas, K Olkiewicz, P Stopa, D Szuba, L Zawiejski, L Adamczyk, T Bold, I Grabowska-Bold, D Kisielewska, AM Kowal, J Łukasik, M Przybycień, L Suszycki, J Szuba, A Kotański, W Slomiński, V Adler, U Behrens, I Bloch, K Borras, G Drews, J Fourletova, A Geiser, D Gladkov, P Göttlicher, O Gutsche, T Haas, W Hain

Abstract:

The ZEUS inclusive differential cross-section data from HERA, for charged and neutral current processes taken with e + and e - beams, together with differential cross-section data on inclusive jet production in e + p scattering and dijet production in γp scattering, have been used in a new NLO QCD analysis to extract the parton distribution functions of the proton. The input of jet-production data constrains the gluon and allows an accurate extraction of alpha s(MZ) at NLO; alphas = 0.1183±0.0028(exp.)±0.0008(model). An additional uncertainty from the choice of scales is estimated as ±0.005. This is the first extraction of alphas(MZ) from HERA data alone. © Springer-Verlag/Società Italiana de Fisica 2005.

Search for right-handed W bosons in top quark decay

Physical Review D - Particles, Fields, Gravitation and Cosmology 72:1 (2005) 1-8

Authors:

VM Abazov, B Abbott, M Abolins, BS Acharya, M Adams, T Adams, M Agelou, JL Agram, SH Ahn, M Ahsan, GD Alexeev, G Alkhazov, A Alton, G Alverson, GA Alves, M Anastasoaie, T Andeen, S Anderson, B Andrieu, Y Arnoud, A Askew, B Åsman, ACSA Jesus, O Atramentov, C Autermann, C Avila, F Badaud, A Baden, B Baldin, PW Balm, S Banerjee, E Barberis, P Bargassa, P Baringer, C Barnes, J Barreto, JF Bartlett, U Bassler, D Bauer, A Bean, S Beauceron, M Begel, A Bellavance, SB Beri, G Bernardi, R Bernhard, 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, U Blumenschein, A Boehnlein, O Boeriu, TA Bolton, F Borcherding, G Borissov, K Bos, T Bose, A Brandt, R Brock, G Brooijmans, A Bross, NJ Buchanan, D Buchholz, M Buehler, V Buescher, S Burdin, TH Burnett, E Busato, CP Buszello, JM Butler, J Cammin, S Caron, W Carvalho, BCK Casey, NM Cason, H Castilla-Valdez, S Chakrabarti, D Chakraborty, KM Chan, A Chandra, D Chapin, F Charles, E Cheu, DK Cho, S Choi, B Choudhary, T Christiansen, L Christofek, D Claes

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 lepton+jets decay mode. These data correspond to an integrated luminosity of 230pb-1, collected by the D0 detector at the Fermilab Tevatron pp̄ Collider at s=1.96TeV. We use a constrained fit to reconstruct the kinematics of the tt̄ and decay products, which allows for the measurement of the leptonic decay angle θ* for each event. By comparing the cos θ* distribution from the data with those for the expected background and signal for various values of f+, we find f+=0.00±0.13(stat) ±0.07(syst). This measurement is consistent with the standard model prediction of f+=3.6×10-4. © 2005 The American Physical Society.