Professor Chris Hays: Publications

Observation of the Ξb0 baryon

Physical Review Letters 107:10 (2011)

Authors:

T Aaltonen, B Álvarez González, S Amerio, D Amidei, A Anastassov, A Annovi, J Antos, G Apollinari, JA Appel, A Apresyan, T Arisawa, A Artikov, J Asaadi, W Ashmanskas, B Auerbach, A Aurisano, F Azfar, W Badgett, A Barbaro-Galtieri, VE Barnes, BA Barnett, P Barria, P Bartos, M Bauce, G Bauer, F Bedeschi, D Beecher, S Behari, G Bellettini, J Bellinger, D Benjamin, A Beretvas, A Bhatti, M Binkley, D Bisello, I Bizjak, KR Bland, B Blumenfeld, A Bocci, A Bodek, D Bortoletto, J Boudreau, A Boveia, L Brigliadori, A Brisuda, C Bromberg, E Brucken, M Bucciantonio, J Budagov, HS Budd, S Budd, K Burkett, G Busetto, P Bussey, A Buzatu, C Calancha, S Camarda, M Campanelli, M Campbell, F Canelli, 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, YC Chen, M Chertok, G Chiarelli, G Chlachidze, F Chlebana, K Cho, D Chokheli, JP Chou, WH Chung, YS Chung, CI Ciobanu, MA Ciocci, A Clark, C Clarke, G Compostella, ME Convery, J Conway, M Corbo, M Cordelli, CA Cox, DJ Cox, F Crescioli, C Cuenca Almenar, J Cuevas, R Culbertson, D Dagenhart

Abstract:

The observation of the bottom, strange baryon Ξb0 through the decay chain Ξb0→Ξc+π-, where Ξc+→Ξ -π+π+, Ξ -→Λπ-, and Λ→pπ-, is reported by using data corresponding to an integrated luminosity of 4.2fb-1 from pp̄ collisions at √s=1.96TeV recorded with the Collider Detector at Fermilab. A signal of 25.3-5.4+5.6 candidates is observed whose probability of arising from a background fluctuation is 3.6×10-12, corresponding to 6.8 Gaussian standard deviations. The Ξb0 mass is measured to be 5787.8±5.0(stat)±1.3(syst)MeV/ c2. In addition, the Ξb- baryon is observed through the process Ξb-→Ξc0π-, where Ξc0→Ξ -π+, Ξ-→Λπ-, and Λ→pπ-. © 2011 American Physical Society.

Measurement of the tt̄ production cross section in pp̄ collisions at √s=1.96TeV using events with large missing transverse energy and jets

Physical Review D - Particles, Fields, Gravitation and Cosmology 84:3 (2011)

Authors:

T Aaltonen, B Álvarez González, S Amerio, D Amidei, A Anastassov, A Annovi, J Antos, G Apollinari, JA Appel, A Apresyan, T Arisawa, A Artikov, J Asaadi, W Ashmanskas, B Auerbach, A Aurisano, F Azfar, W Badgett, A Barbaro-Galtieri, VE Barnes, BA Barnett, P Barria, P Bartos, M Bauce, G Bauer, F Bedeschi, D Beecher, S Behari, G Bellettini, J Bellinger, D Benjamin, A Beretvas, A Bhatti, M Binkley, D Bisello, I Bizjak, KR Bland, B Blumenfeld, A Bocci, A Bodek, D Bortoletto, J Boudreau, A Boveia, B Brau, L Brigliadori, A Brisuda, C Bromberg, E Brucken, M Bucciantonio, J Budagov, HS Budd, S Budd, K Burkett, G Busetto, P Bussey, A Buzatu, 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, YC Chen, M Chertok, G Chiarelli, G Chlachidze, F Chlebana, K Cho, D Chokheli, JP Chou, WH Chung, YS Chung, CI Ciobanu, MA Ciocci, A Clark, G Compostella, ME Convery, J Conway, M Corbo, M Cordelli, CA Cox, DJ Cox, F Crescioli, C Cuenca Almenar, J Cuevas, R Culbertson

Abstract:

In this paper we report a measurement of the tt̄ production cross section in pp̄ collisions at √s=1.96TeV using data corresponding to an integrated luminosity of 2.2fb-1 collected with the CDF II detector at the Tevatron accelerator. We select events with significant missing transverse energy and high jet multiplicity. This measurement vetoes the presence of explicitly identified electrons and muons, thus enhancing the tau contribution of tt̄ decays. Signal events are discriminated from the background using a neural network, and heavy flavor jets are identified by a secondary-vertex tagging algorithm. We measure a tt̄ production cross section of 7.99±0.55(stat)±0.76(syst)±0.46(lumi) pb, assuming a top mass mtop=172.5GeV/c2, in agreement with previous measurements and standard model predictions. © 2011 American Physical Society.

Search for WZ+ZZ production with MET + jets with b enhancement at sqrt(s) = 1.96 TeV

(2011)

Authors:

CDF Collaboration, T Aaltonen, B Álvarez Gonzálezv, S Amerio, D Amidei, A Anastassov, A Annovi, J Antos, G Apollinari, JA Appel, A Apresyan, T Arisawa, A Artikov, J Asaadi, W Ashmanskas, B Auerbach, A Aurisano, F Azfar, W Badgett, A Barbaro-Galtieri, VE Barnes, BA Barnett, P Barriaee, P Bartos, M Baucecc, G Bauer, F Bedeschi, D Beecher, S Behari, G Bellettinidd, J Bellinger, D Benjamin, A Beretvas, A Bhatti, M Binkley, D Bisellocc, I Bizjakii, KR Bland, C Blocker, B Blumenfeld, A Bocci, A Bodek, D Bortoletto, J Boudreau, A Boveia, B Braua, L Brigliadoribb, A Brisuda, C Bromberg, E Brucken, M Bucciantoniodd, J Budagov, HS Budd, S Budd, K Burkett, G Busettocc, P Bussey, A Buzatu, S Cabrerax, C Calancha, S Camarda, M Campanelli, M Campbell, F Canelli, A Canepa, B Carls, D Carlsmith, R Carosi, S Carrillok, S Carron, B Casal, M Casarsa, A Castrobb, P Catastini, D Cauz, V Cavaliereee, M Cavalli-Sforza, A Cerrif, L Cerritoq, YC Chen, M Chertok, G Chiarelli, G Chlachidze, F Chlebana, K Cho, D Chokheli, JP Chou, WH Chung, YS Chung, CI Ciobanu, MA Ciocciee, A Clark, D Clark, G Compostellacc, ME Convery, J Conway, M Corbo, M Cordelli, CA Cox, DJ Cox, F Cresciolidd, C Cuenca Almenar, J Cuevasv, R Culbertson, D Dagenhart, N d'Ascenzot, M Datta, P de Barbaro, S De Cecco, G De Lorenzo, M Dell'Orsodd, C Deluca, L Demortier, J Dengc, M Deninno, F Devoto, M d'Erricocc, A Di Cantodd, B Di Ruzza, JR Dittmann, M D'Onofrio, S Donatidd, P Dong, T Dorigo, K Ebina, A Elagin, A Eppig, R Erbacher, D Errede, S Errede, N Ershaidataa, R Eusebi, HC Fang, S Farrington, M Feindt, JP Fernandez, C Ferrazzaff, R Field, G Flanaganr, R Forrest, MJ Frank, M Franklin, JC Freeman, I Furic, M Gallinaro, J Galyardt, JE Garcia, AF Garfinkel, P Garosiee, H Gerberich, E Gerchtein, S Giagugg, V Giakoumopoulou, P Giannetti, K Gibson, CM Ginsburg, N Giokaris, P Giromini, M Giunta, G Giurgiu, V Glagolev, D Glenzinski, M Gold, D Goldin, 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, RC Group, J Guimaraes da Costa, Z Gunay-Unalan, C Haber, SR Hahn, E Halkiadakis, A Hamaguchi, JY Han, F Happacher, K Hara, D Hare, M Hare, RF Harr, K Hatakeyama, C Hays, M Heck, J Heinrich, M Herndon, S Hewamanage, D Hidas, A Hocker, W Hopkins, D Horn, S Hou, RE Hughes, M Hurwitz, U Husemann, N Hussain, M Hussein, J Huston, G Introzzi, M Iorigg, A Ivanovo, E James, D Jang, B Jayatilaka, EJ Jeon, MK Jha, S Jindariani, W Johnson, M Jones, KK Joo, SY Jun, TR Junk, T Kamon, PE Karchin, Y Katon, W Ketchum, J Keung, V Khotilovich, B Kilminster, DH Kim, HS Kim, HW Kim, JE Kim, MJ Kim, SB Kim, SH Kim, YK Kim, N Kimura, S Klimenko, K Kondo, DJ Kong, J Konigsberg, A Korytov, AV Kotwal, M Kreps, J Kroll, D Krop, N Krumnackl, M Kruse, V Krutelyovd, T Kuhr, M Kurata, S Kwang, AT Laasanen, S Lami, S Lammel, M Lancaster, RL Lander, K Lannonu, A Lath, G Latinoee, I Lazzizzera, T LeCompte, E Lee, HS Lee, JS Lee, SW Leew, S Leodd, S Leone, JD Lewis, C-J Lin, J Linacre, M Lindgren, E Lipeles, A Lister, DO Litvintsev, C Liu, Q Liu, T Liu, S Lockwitz, NS Lockyer, A Loginov, D Lucchesicc, J Lueck, P Lujan, P Lukens, G Lungu, J Lys, R Lysak, R Madrak, K Maeshima, K Makhoul, P Maksimovic, S Malik, G Mancab, A Manousakis-Katsikakis, F Margaroli, C Marino, M Martínez, R Martínez-Ballarín, P Mastrandrea, M Mathis, ME Mattson, P Mazzanti, KS McFarland, P McIntyre, R McNultyi, A Mehta, P Mehtala, A Menzione, C Mesropian, T Miao, D Mietlicki, A Mitra, H Miyake, S Moed, N Moggi, MN Mondragonk, CS Moon, R Moore, MJ Morello, J Morlock, P Movilla Fernandez, A Mukherjee, Th Muller, P Murat, M Mussinibb, J Nachtmanm, Y Nagai, J Naganoma, I Nakano, A Napier, J Nett, C Neuz, MS Neubauer, J Nielsene, L Nodulman, O Norniella, E Nurse, L Oakes, SH Oh, YD Oh, I Oksuzian, T Okusawa, R Orava, L Ortolan, S Pagan Grisocc, C Pagliarone, E Palenciaf, V Papadimitriou, AA Paramonov, J Patrick, G Paulettahh, M Paulini, C Paus, DE Pellett, A Penzo, TJ Phillips, G Piacentino, E Pianori, J Pilot, K Pitts, C Plager, L Pondrom, S Poprocki, K Potamianos, O Poukhov, F Prokoshiny, A Pronko, F Ptohosh, E Pueschel, G Punzidd, J Pursley, A Rahaman, V Ramakrishnan, N Ranjan, I Redondo, P Renton, M Rescigno, F Rimondibb, L Ristori, A Robson, T Rodrigo, T Rodriguez, E Rogers, S Rolli, R Roser, M Rossi, F Ruffiniee, A Ruiz, J Russ, V Rusu, A Safonov, WK Sakumoto, L Santihh, L Sartori, K Sato, V Savelievt, A Savoy-Navarro, P Schlabach, A Schmidt, EE Schmidt, MP Schmidt, M Schmitt, T Schwarz, L Scodellaro, A Scribanoee, F Scuri, A Sedov, S Seidel, Y Seiya, A Semenov, F Sforzadd, A Sfyrla, SZ Shalhout, T Shears, PF Shepard, M Shimojimas, S Shiraishi, M Shochet, I Shreyber, A Simonenko, P Sinervo, A Sissakian, K Sliwa, JR Smith, FD Snider, A Soha, S Somalwar, V Sorin, P Squillacioti, M Stanitzki, R St Denis, B Stelzer, O Stelzer-Chilton, D Stentz, J Strologas, GL Strycker, Y Sudo, A Sukhanov, I Suslov, K Takemasa, Y Takeuchi, J Tang, M Tecchio, PK Teng, J Thom, J Thome, GA Thompson, E Thomson, P Ttito-Guzmán, S Tkaczyk, D Toback, S Tokar, K Tollefson, T Tomura, D Tonelli, S Torre, D Torretta, P Totarohh, M Trovatoff, Y Tu, N Turiniee, F Ukegawa, S Uozumi, A Varganov, E Vatagaff, F Vázquez, G Velev, C Vellidis, M Vidal, I Vila, R Vilar, M Vogel, G Volpidd, P Wagner, RL Wagner, T Wakisaka, R Wallny, SM Wang, A Warburton, D Waters, M Weinberger, WC Wester, B Whitehouse, D Whitesonc, AB Wicklund, E Wicklund, S Wilbur, F Wick, HH Williams, JS Wilson, P Wilson, BL Winer, P Wittich, S Wolbers, H Wolfe, T Wright, X Wu, Z Wu, K Yamamoto, J Yamaoka, T Yang, UK Yangp, YC Yang, W-M Yao, GP Yeh, K Yim, J Yoh, K Yorita, T Yoshidaj, GB Yu, I Yu, SS Yu, JC Yun, A Zanetti, Y Zeng, S Zucchelli

Measurement of the top-quark mass in the lepton+jets channel using a matrix element technique with the CDF II detector

(2011)

Authors:

CDF Collaboration, T Aaltonen, B Álvarez Gonzálezv, S Amerio, D Amidei, A Anastassov, A Annovi, J Antos, G Apollinari, JA Appel, A Apresyan, T Arisawa, A Artikov, J Asaadi, W Ashmanskas, B Auerbach, A Aurisano, F Azfar, W Badgett, A Barbaro-Galtieri, VE Barnes, BA Barnett, P Barriaee, P Bartos, M Baucecc, G Bauer, F Bedeschi, D Beecher, S Behari, G Bellettinidd, J Bellinger, D Benjamin, A Beretvas, A Bhatti, M Binkley, D Bisellocc, I Bizjakii, KR Bland, C Blocker, B Blumenfeld, A Bocci, A Bodek, D Bortoletto, J Boudreau, A Boveia, B Braua, L Brigliadoribb, A Brisuda, C Bromberg, E Brucken, M Bucciantoniodd, J Budagov, HS Budd, S Budd, K Burkett, G Busettocc, P Bussey, A Buzatu, S Cabrerax, C Calancha, S Camarda, M Campanelli, M Campbell, F Canelli, A Canepa, B Carls, D Carlsmith, R Carosi, S Carrillok, S Carron, B Casal, M Casarsa, A Castrobb, P Catastini, D Cauz, V Cavaliereee, M Cavalli-Sforza, A Cerrif, L Cerritoq, YC Chen, M Chertok, G Chiarelli, G Chlachidze, F Chlebana, K Cho, D Chokheli, JP Chou, WH Chung, YS Chung, CI Ciobanu, MA Ciocciee, A Clark, D Clark, G Compostellacc, ME Convery, J Conway, M Corbo, M Cordelli, CA Cox, DJ Cox, F Cresciolidd, C Cuenca Almenar, J Cuevasv, R Culbertson, D Dagenhart, N d'Ascenzot, M Datta, P de Barbaro, S De Cecco, G De Lorenzo, M Dell'Orsodd, C Deluca, L Demortier, J Dengc, M Deninno, F Devoto, M d'Erricocc, A Di Cantodd, B Di Ruzza, JR Dittmann, M D'Onofrio, S Donatidd, P Dong, T Dorigo, K Ebina, A Elagin, A Eppig, R Erbacher, D Errede, S Errede, N Ershaidataa, R Eusebi, HC Fang, S Farrington, M Feindt, JP Fernandez, C Ferrazzaff, R Field, G Flanaganr, R Forrest, MJ Frank, M Franklin, JC Freeman, I Furic, M Gallinaro, J Galyardt, JE Garcia, AF Garfinkel, P Garosiee, H Gerberich, E Gerchtein, S Giagugg, V Giakoumopoulou, P Giannetti, K Gibson, CM Ginsburg, N Giokaris, P Giromini, M Giunta, G Giurgiu, V Glagolev, D Glenzinski, M Gold, D Goldin, 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, RC Group, J Guimaraes da Costa, Z Gunay-Unalan, C Haber, SR Hahn, E Halkiadakis, A Hamaguchi, JY Han, F Happacher, K Hara, D Hare, M Hare, RF Harr, K Hatakeyama, C Hays, M Heck, J Heinrich, M Herndon, S Hewamanage, D Hidas, A Hocker, W Hopkinsg, D Horn, S Hou, RE Hughes, M Hurwitz, U Husemann, N Hussain, M Hussein, J Huston, G Introzzi, M Iorigg, A Ivanovo, E James, D Jang, B Jayatilaka, EJ Jeon, MK Jha, S Jindariani, W Johnson, M Jones, KK Joo, SY Jun, TR Junk, T Kamon, PE Karchin, Y Katon, W Ketchum, J Keung, V Khotilovich, B Kilminster, DH Kim, HS Kim, HW Kim, JE Kim, MJ Kim, SB Kim, SH Kim, YK Kim, N Kimura, S Klimenko, K Kondo, DJ Kong, J Konigsberg, A Korytov, AV Kotwal, M Kreps, J Kroll, D Krop, N Krumnackl, M Kruse, V Krutelyovd, T Kuhr, M Kurata, S Kwang, AT Laasanen, S Lami, S Lammel, M Lancaster, RL Lander, K Lannonu, A Lath, G Latinoee, I Lazzizzera, T LeCompte, E Lee, HS Lee, JS Lee, SW Leew, S Leodd, S Leone, JD Lewis, C-J Lin, J Linacre, M Lindgren, E Lipeles, A Lister, DO Litvintsev, C Liu, Q Liu, T Liu, S Lockwitz, NS Lockyer, A Loginov, D Lucchesicc, J Lueck, P Lujan, P Lukens, G Lungu, J Lys, R Lysak, R Madrak, K Maeshima, K Makhoul, P Maksimovic, S Malik, G Mancab, A Manousakis-Katsikakis, F Margaroli, C Marino, M Martínez, R Martínez-Ballarín, P Mastrandrea, M Mathis, ME Mattson, P Mazzanti, KS McFarland, P McIntyre, R McNultyi, A Mehta, P Mehtala, A Menzione, C Mesropian, T Miao, D Mietlicki, A Mitra, H Miyake, S Moed, N Moggi, MN Mondragonk, CS Moon, R Moore, MJ Morello, J Morlock, P Movilla Fernandez, A Mukherjee, Th Muller, P Murat, M Mussinibb, J Nachtmanm, Y Nagai, J Naganoma, I Nakano, A Napier, J Nett, C Neuz, MS Neubauer, J Nielsene, L Nodulman, O Norniella, E Nurse, L Oakes, SH Oh, YD Oh, I Oksuzian, T Okusawa, R Orava, L Ortolan, S Pagan Grisocc, C Pagliarone, E Palenciaf, V Papadimitriou, AA Paramonov, J Patrick, G Paulettahh, M Paulini, C Paus, DE Pellett, A Penzo, TJ Phillips, G Piacentino, E Pianori, J Pilot, K Pitts, C Plager, L Pondrom, K Potamianos, O Poukhov, F Prokoshiny, A Pronko, F Ptohosh, E Pueschel, G Punzidd, J Pursley, A Rahaman, V Ramakrishnan, N Ranjan, I Redondo, P Renton, M Rescigno, F Rimondibb, L Ristori, A Robson, T Rodrigo, T Rodriguez, E Rogers, S Rolli, R Roser, M Rossi, F Ruffiniee, A Ruiz, J Russ, V Rusu, A Safonov, WK Sakumoto, L Santihh, L Sartori, K Sato, V Savelievt, A Savoy-Navarro, P Schlabach, A Schmidt, EE Schmidt, MP Schmidt, M Schmitt, T Schwarz, L Scodellaro, A Scribanoee, F Scuri, A Sedov, S Seidel, Y Seiya, A Semenov, F Sforzadd, A Sfyrla, SZ Shalhout, T Shears, PF Shepard, M Shimojimas, S Shiraishi, M Shochet, I Shreyber, A Simonenko, P Sinervo, A Sissakian, K Sliwa, JR Smith, FD Snider, A Soha, S Somalwar, V Sorin, P Squillacioti, M Stanitzki, R St Denis, B Stelzer, O Stelzer-Chilton, D Stentz, J Strologas, GL Strycker, Y Sudo, A Sukhanov, I Suslov, K Takemasa, Y Takeuchi, J Tang, M Tecchio, PK Teng, J Thomg, J Thome, GA Thompson, E Thomson, P Ttito-Guzmán, S Tkaczyk, D Toback, S Tokar, K Tollefson, T Tomura, D Tonelli, S Torre, D Torretta, P Totarohh, M Trovatoff, Y Tu, N Turiniee, F Ukegawa, S Uozumi, A Varganov, E Vatagaff, F Vázquez, G Velev, C Vellidis, M Vidal, I Vila, R Vilar, M Vogel, G Volpidd, P Wagner, RL Wagner, T Wakisaka, R Wallny, SM Wang, A Warburton, D Waters, M Weinberger, WC Wester, B Whitehouse, D Whitesonc, AB Wicklund, E Wicklund, S Wilbur, F Wick, HH Williams, JS Wilson, P Wilson, BL Winer, P Wittichg, S Wolbers, H Wolfe, T Wright, X Wu, Z Wu, K Yamamoto, J Yamaoka, T Yang, UK Yangp, YC Yang, W-M Yao, GP Yeh, K Yim, J Yoh, K Yorita, T Yoshidaj, GB Yu, I Yu, SS Yu, JC Yun, A Zanetti, Y Zeng, S Zucchelli

Measurement of the top pair production cross section in the lepton+jets channel using a jet flavor discriminant

Physical Review D - Particles, Fields, Gravitation and Cosmology 84:3 (2011)

Authors:

T Aaltonen, B Álvarez González, S Amerio, D Amidei, A Anastassov, A Annovi, J Antos, G Apollinari, JA Appel, A Apresyan, T Arisawa, A Artikov, J Asaadi, W Ashmanskas, B Auerbach, A Aurisano, F Azfar, W Badgett, A Barbaro-Galtieri, VE Barnes, BA Barnett, P Barria, P Bartos, M Bauce, G Bauer, F Bedeschi, D Beecher, S Behari, G Bellettini, J Bellinger, D Benjamin, A Beretvas, A Bhatti, M Binkley, D Bisello, I Bizjak, KR Bland, B Blumenfeld, A Bocci, A Bodek, D Bortoletto, J Boudreau, A Boveia, B Brau, L Brigliadori, A Brisuda, C Bromberg, E Brucken, M Bucciantonio, J Budagov, HS Budd, S Budd, K Burkett, G Busetto, P Bussey, A Buzatu, 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, YC Chen, M Chertok, G Chiarelli, G Chlachidze, F Chlebana, K Cho, D Chokheli, JP Chou, WH Chung, YS Chung, CI Ciobanu, MA Ciocci, A Clark, G Compostella, ME Convery, J Conway, M Corbo, M Cordelli, CA Cox, DJ Cox, F Crescioli, C Cuenca Almenar, J Cuevas, R Culbertson

Abstract:

We present a new method to measure the top quark pair production cross section and the background rates with data corresponding to an integrated luminosity of 2.7fb-1 from pp̄ collisions at √s=1.96TeV collected with the CDF II Detector. We select events with a single electron or muon candidate, missing transverse energy, and at least one b-tagged jet. We perform a simultaneous fit to a jet flavor discriminant across nine samples defined by the number of jets and b tags. An advantage of this approach is that many systematic uncertainties are measured in situ and inversely scale with integrated luminosity. We measure a top cross section of σ tt̄=7.64±0.57(stat+syst)±0.45(luminosity)pb. © 2011 American Physical Society.

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