Evidence for a mass dependent forward-backward asymmetry in top quark pair production

Physical Review D - Particles, Fields, Gravitation and Cosmology 83:11 (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 measurement of the inclusive forward-backward tt̄ production asymmetry and its rapidity and mass dependence. The measurements are performed with data corresponding to an integrated luminosity of 5.3fb -1 of pp̄ collisions at √s=1.96TeV, recorded with the CDF-II Detector at the Fermilab Tevatron. Significant inclusive asymmetries are observed in both the laboratory frame and the tt̄ rest frame, and in both cases are found to be consistent with CP conservation under interchange of t and t̄. In the tt̄ rest frame, the asymmetry is observed to increase with the tt̄ rapidity difference, Δy, and with the invariant mass M tt̄ of the tt̄ system. Fully corrected parton-level asymmetries are derived in two regions of each variable, and the asymmetry is found to be most significant at large Δy and Mtt̄. For Mtt̄?450GeV/c2, the parton-level asymmetry in the tt̄ rest frame is Att̄=0.475±0.114 compared to a next-to-leading order QCD prediction of 0.088±0.013. © 2011 American Physical Society.

The T2K Experiment

Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment Elsevier 659:1 (2011) 106-135

Authors:

N Abgrall, H Aihara, Y Ajima, JB Albert, D Allan, PA Amaudruz, C Andreopoulos, B Andrieu, C Angelsen, S Aoki, O Araoka, J Argyriades, A Ariga, T Ariga, S Assylbekov, JPAMD Andre, D Autiero, A Badertscher, O Ballester, M Barbi, GJ Barker, P Baron, Giles Barr, L Bartoszek, M Batkiewicz, F Bay, S Bentham, V Berardi, BE Berger, H Berns, I Bertram, M Besnier, J Beucher, D Beznosko, S Bhadra, P Birney, D Bishop, E Blackmore, FDM Blaszczyk, J Blocki, A Blondel, A Bodek, C Bojechko, J Bouchez, T Boussuge, SB Boyd, M Boyer, N Braam

Abstract:

The T2K experiment is a long-baseline neutrino oscillation experiment. Its main goal is to measure the last unknown lepton sector mixing angle {\theta}_{13} by observing {\nu}_e appearance in a {\nu}_{\mu} beam. It also aims to make a precision measurement of the known oscillation parameters, {\Delta}m^{2}_{23} and sin^{2} 2{\theta}_{23}, via {\nu}_{\mu} disappearance studies. Other goals of the experiment include various neutrino cross section measurements and sterile neutrino searches. The experiment uses an intense proton beam generated by the J-PARC accelerator in Tokai, Japan, and is composed of a neutrino beamline, a near detector complex (ND280), and a far detector (Super-Kamiokande) located 295 km away from J-PARC. This paper provides a comprehensive review of the instrumentation aspect of the T2K experiment and a summary of the vital information for each subsystem.

The T2K Experiment

ArXiv 1106.1238 (2011)

Authors:

T2K Collaboration, K Abe, N Abgrall, H Aihara, Y Ajima, JB Albert, D Allan, P-A Amaudruz, C Andreopoulos, B Andrieu, MD Anerella, C Angelsen, S Aoki, O Araoka, J Argyriades, A Ariga, T Ariga, S Assylbekov, JPAM de André, D Autiero, A Badertscher, O Ballester, M Barbi, GJ Barker, P Baron, G Barr, L Bartoszek, M Batkiewicz, F Bay, S Bentham, V Berardi, BE Berger, H Berns, I Bertram, M Besnier, J Beucher, D Beznosko, S Bhadra, P Birney, D Bishop, E Blackmore, FDM Blaszczyk, J Blocki, A Blondel, A Bodek, C Bojechko, J Bouchez, T Boussuge, SB Boyd, M Boyer, N Braam, R Bradford, A Bravar, K Briggs, JD Brinson, C Bronner, DG Brook-Roberge, M Bryant, N Buchanan, H Budd, M Cadabeschi, RG Calland, D Calvet, J Caravaca Rodríguez, J Carroll, SL Cartwright, A Carver, R Castillo, MG Catanesi, C Cavata, A Cazes, A Cervera, JP Charrier, C Chavez, S Choi, S Chollet, G Christodoulou, P Colas, J Coleman, W Coleman, G Collazuol, K Connolly, P Cooke, A Curioni, A Dabrowska, I Danko, R Das, GS Davies, S Davis, M Day, X De La Broise, P de Perio, G De Rosa, T Dealtry, A Debraine, E Delagnes, A Delbart, C Densham, F Di Lodovico, S Di Luise, P Dinh Tran, J Dobson, J Doornbos, U Dore, O Drapier, F Druillole, F Dufour, J Dumarchez, T Durkin, S Dytman, M Dziewiecki, M Dziomba, B Ellison, S Emery, A Ereditato, JE Escallier, L Escudero, LS Esposito, W Faszer, M Fechner, A Ferrero, A Finch, C Fisher, M Fitton, R Flight, D Forbush, E Frank, K Fransham, Y Fujii, Y Fukuda, M Gallop, V Galymov, GL Ganetis, FC Gannaway, A Gaudin, J Gaweda, A Gendotti, M George, S Giffin, C Giganti, K Gilje, I Giomataris, J Giraud, AK Ghosh, T Golan, M Goldhaber, JJ Gomez-Cadenas, S Gomi, M Gonin, M Goyette, A Grant, N Grant, F Grañena, S Greenwood, P Gumplinger, P Guzowski, MD Haigh, K Hamano, C Hansen, T Hara, PF Harrison, B Hartfiel, M Hartz, T Haruyama, R Hasanen, T Hasegawa, NC Hastings, S Hastings, A Hatzikoutelis, K Hayashi, Y Hayato, TDJ Haycock, C Hearty, RL Helmer, R Henderson, S Herlant, N Higashi, J Hignight, K Hiraide, E Hirose, J Holeczek, N Honkanen, S Horikawa, A Hyndman, AK Ichikawa, K Ieki, M Ieva, M Iida, M Ikeda, J Ilic, J Imber, T Ishida, C Ishihara, T Ishii, SJ Ives, M Iwasaki, K Iyogi, A Izmaylov, B Jamieson, RA Johnson, KK Joo, G Jover-Manas, CK Jung, H Kaji, T Kajita, H Kakuno, J Kameda, K Kaneyuki, D Karlen, K Kasami, V Kasey, I Kato, H Kawamuko, E Kearns, L Kellet, M Khabibullin, M Khaleeq, N Khan, A Khotjantsev, D Kielczewska, T Kikawa, JY Kim, S-B Kim, N Kimura, B Kirby, J Kisiel, P Kitching, T Kobayashi, G Kogan, S Koike, T Komorowski, A Konaka, LL Kormos, A Korzenev, K Koseki, Y Koshio, Y Kouzuma, K Kowalik, V Kravtsov, I Kreslo, W Kropp, H Kubo, J Kubota, Y Kudenko, N Kulkarni, L Kurchaninov, Y Kurimoto, R Kurjata, Y Kurosawa, T Kutter, J Lagoda, K Laihem, R Langstaff, M Laveder, TB Lawson, PT Le, A Le Coguie, M Le Ross, KP Lee, M Lenckowski, C Licciardi, IT Lim, T Lindner, RP Litchfield, A Longhin, GD Lopez, P Lu, L Ludovici, T Lux, M Macaire, L Magaletti, K Mahn, Y Makida, CJ Malafis, M Malek, S Manly, A Marchionni, C Mark, AD Marino, AJ Marone, J Marteau, JF Martin, T Maruyama, T Maryon, J Marzec, P Masliah, EL Mathie, C Matsumura, K Matsuoka, V Matveev, K Mavrokoridis, E Mazzucato, N McCauley, KS McFarland, C McGrew, T McLachlan, I Mercer, M Messina, W Metcalf, C Metelko, M Mezzetto, P Mijakowski, CA Miller, A Minamino, O Mineev, S Mine, RE Minvielle, G Mituka, M Miura, K Mizouchi, J-P Mols, L Monfregola, E Monmarthe, F Moreau, B Morgan, S Moriyama, D Morris, A Muir, A Murakami, JF Muratore, M Murdoch, S Murphy, J Myslik, G Nagashima, T Nakadaira, M Nakahata, T Nakamoto, K Nakamura, S Nakayama, T Nakaya, D Naples, B Nelson, TC Nicholls, K Nishikawa, H Nishino, K Nitta, F Nizery, JA Nowak, M Noy, Y Obayashi, T Ogitsu, H Ohhata, T Okamura, K Okumura, T Okusawa, C Ohlmann, K Olchanski, R Openshaw, SM Oser, M Otani, RA Owen, Y Oyama, T Ozaki, MY Pac, V Palladino, V Paolone, P Paul, D Payne, GF Pearce, C Pearson, JD Perkin, M Pfleger, F Pierre, D Pierrepont, P Plonski, P Poffenberger, E Poplawska, B Popov, M Posiadala, J-M Poutissou, R Poutissou, R Preece, P Przewlocki, W Qian, JL Raaf, E Radicioni, K Ramos, P Ratoff, TM Raufer, M Ravonel, M Raymond, F Retiere, D Richards, J-L Ritou, A Robert, PA Rodrigues, E Rondio, M Roney, M Rooney, D Ross, B Rossi, S Roth, A Rubbia, D Ruterbories, R Sacco, S Sadler, K Sakashita, F Sanchez, A Sarrat, K Sasaki, P Schaack, J Schmidt, K Scholberg, J Schwehr, M Scott, DI Scully, Y Seiya, T Sekiguchi, H Sekiya, G Sheffer, M Shibata, Y Shimizu, M Shiozawa, S Short, M Siyad, D Smith, RJ Smith, M Smy, J Sobczyk, H Sobel, S Sooriyakumaran, M Sorel, J Spitz, A Stahl, P Stamoulis, O Star, J Statter, L Stawnyczy, J Steinmann, J Steffens, B Still, M Stodulski, J Stone, C Strabel, T Strauss, R Sulej, P Sutcliffe, A Suzuki, K Suzuki, S Suzuki, SY Suzuki, Y Suzuki, Y Suzuki, J Swierblewski, T Szeglowski, M Szeptycka, R Tacik, M Tada, AS Tadepalli, M Taguchi, S Takahashi, A Takeda, Y Takenaga, Y Takeuchi, HA Tanaka, K Tanaka, M Tanaka, MM Tanaka, N Tanimoto, K Tashiro, IJ Taylor, A Terashima, D Terhorst, R Terri, LF Thompson, A Thorley, M Thorpe, W Toki, T Tomaru, Y Totsuka, C Touramanis, T Tsukamoto, V Tvaskis, M Tzanov, Y Uchida, K Ueno, M Usseglio, A Vacheret, M Vagins, JF Van Schalkwyk, J-C Vanel, G Vasseur, O Veledar, P Vincent, T Wachala, AV Waldron, CW Walter, PJ Wanderer, MA Ward, GP Ward, D Wark, D Warner, MO Wascko, A Weber, R Wendell, J Wendland, N West, LH Whitehead, G Wikström, RJ Wilkes, MJ Wilking, Z Williamson, JR Wilson, RJ Wilson, K Wong, T Wongjirad, S Yamada, Y Yamada, A Yamamoto, K Yamamoto, Y Yamanoi, H Yamaoka, C Yanagisawa, T Yano, S Yen, N Yershov, M Yokoyama, A Zalewska, J Zalipska, K Zaremba, M Ziembicki, ED Zimmerman, M Zito, J Zmuda

Abstract:

The T2K experiment is a long-baseline neutrino oscillation experiment. Its main goal is to measure the last unknown lepton sector mixing angle {\theta}_{13} by observing {\nu}_e appearance in a {\nu}_{\mu} beam. It also aims to make a precision measurement of the known oscillation parameters, {\Delta}m^{2}_{23} and sin^{2} 2{\theta}_{23}, via {\nu}_{\mu} disappearance studies. Other goals of the experiment include various neutrino cross section measurements and sterile neutrino searches. The experiment uses an intense proton beam generated by the J-PARC accelerator in Tokai, Japan, and is composed of a neutrino beamline, a near detector complex (ND280), and a far detector (Super-Kamiokande) located 295 km away from J-PARC. This paper provides a comprehensive review of the instrumentation aspect of the T2K experiment and a summary of the vital information for each subsystem.

The T2K Experiment

(2011)

Authors:

T2K Collaboration, K Abe, N Abgrall, H Aihara, Y Ajima, JB Albert, D Allan, P-A Amaudruz, C Andreopoulos, B Andrieu, MD Anerella, C Angelsen, S Aoki, O Araoka, J Argyriades, A Ariga, T Ariga, S Assylbekov, JPAM de André, D Autiero, A Badertscher, O Ballester, M Barbi, GJ Barker, P Baron, G Barr, L Bartoszek, M Batkiewicz, F Bay, S Bentham, V Berardi, BE Berger, H Berns, I Bertram, M Besnier, J Beucher, D Beznosko, S Bhadra, P Birney, D Bishop, E Blackmore, FDM Blaszczyk, J Blocki, A Blondel, A Bodek, C Bojechko, J Bouchez, T Boussuge, SB Boyd, M Boyer, N Braam, R Bradford, A Bravar, K Briggs, JD Brinson, C Bronner, DG Brook-Roberge, M Bryant, N Buchanan, H Budd, M Cadabeschi, RG Calland, D Calvet, J Caravaca Rodríguez, J Carroll, SL Cartwright, A Carver, R Castillo, MG Catanesi, C Cavata, A Cazes, A Cervera, JP Charrier, C Chavez, S Choi, S Chollet, G Christodoulou, P Colas, J Coleman, W Coleman, G Collazuol, K Connolly, P Cooke, A Curioni, A Dabrowska, I Danko, R Das, GS Davies, S Davis, M Day, X De La Broise, P de Perio, G De Rosa, T Dealtry, A Debraine, E Delagnes, A Delbart, C Densham, F Di Lodovico, S Di Luise, P Dinh Tran, J Dobson, J Doornbos, U Dore, O Drapier, F Druillole, F Dufour, J Dumarchez, T Durkin, S Dytman, M Dziewiecki, M Dziomba, B Ellison, S Emery, A Ereditato, JE Escallier, L Escudero, LS Esposito, W Faszer, M Fechner, A Ferrero, A Finch, C Fisher, M Fitton, R Flight, D Forbush, E Frank, K Fransham, Y Fujii, Y Fukuda, M Gallop, V Galymov, GL Ganetis, FC Gannaway, A Gaudin, J Gaweda, A Gendotti, M George, S Giffin, C Giganti, K Gilje, I Giomataris, J Giraud, AK Ghosh, T Golan, M Goldhaber, JJ Gomez-Cadenas, S Gomi, M Gonin, M Goyette, A Grant, N Grant, F Grañena, S Greenwood, P Gumplinger, P Guzowski, MD Haigh, K Hamano, C Hansen, T Hara, PF Harrison, B Hartfiel, M Hartz, T Haruyama, R Hasanen, T Hasegawa, NC Hastings, S Hastings, A Hatzikoutelis, K Hayashi, Y Hayato, TDJ Haycock, C Hearty, RL Helmer, R Henderson, S Herlant, N Higashi, J Hignight, K Hiraide, E Hirose, J Holeczek, N Honkanen, S Horikawa, A Hyndman, AK Ichikawa, K Ieki, M Ieva, M Iida, M Ikeda, J Ilic, J Imber, T Ishida, C Ishihara, T Ishii, SJ Ives, M Iwasaki, K Iyogi, A Izmaylov, B Jamieson, RA Johnson, KK Joo, G Jover-Manas, CK Jung, H Kaji, T Kajita, H Kakuno, J Kameda, K Kaneyuki, D Karlen, K Kasami, V Kasey, I Kato, H Kawamuko, E Kearns, L Kellet, M Khabibullin, M Khaleeq, N Khan, A Khotjantsev, D Kielczewska, T Kikawa, JY Kim, S-B Kim, N Kimura, B Kirby, J Kisiel, P Kitching, T Kobayashi, G Kogan, S Koike, T Komorowski, A Konaka, LL Kormos, A Korzenev, K Koseki, Y Koshio, Y Kouzuma, K Kowalik, V Kravtsov, I Kreslo, W Kropp, H Kubo, J Kubota, Y Kudenko, N Kulkarni, L Kurchaninov, Y Kurimoto, R Kurjata, Y Kurosawa, T Kutter, J Lagoda, K Laihem, R Langstaff, M Laveder, TB Lawson, PT Le, A Le Coguie, M Le Ross, KP Lee, M Lenckowski, C Licciardi, IT Lim, T Lindner, RP Litchfield, A Longhin, GD Lopez, P Lu, L Ludovici, T Lux, M Macaire, L Magaletti, K Mahn, Y Makida, CJ Malafis, M Malek, S Manly, A Marchionni, C Mark, AD Marino, AJ Marone, J Marteau, JF Martin, T Maruyama, T Maryon, J Marzec, P Masliah, EL Mathie, C Matsumura, K Matsuoka, V Matveev, K Mavrokoridis, E Mazzucato, N McCauley, KS McFarland, C McGrew, T McLachlan, I Mercer, M Messina, W Metcalf, C Metelko, M Mezzetto, P Mijakowski, CA Miller, A Minamino, O Mineev, S Mine, RE Minvielle, G Mituka, M Miura, K Mizouchi, J-P Mols, L Monfregola, E Monmarthe, F Moreau, B Morgan, S Moriyama, D Morris, A Muir, A Murakami, JF Muratore, M Murdoch, S Murphy, J Myslik, G Nagashima, T Nakadaira, M Nakahata, T Nakamoto, K Nakamura, S Nakayama, T Nakaya, D Naples, B Nelson, TC Nicholls, K Nishikawa, H Nishino, K Nitta, F Nizery, JA Nowak, M Noy, Y Obayashi, T Ogitsu, H Ohhata, T Okamura, K Okumura, T Okusawa, C Ohlmann, K Olchanski, R Openshaw, SM Oser, M Otani, RA Owen, Y Oyama, T Ozaki, MY Pac, V Palladino, V Paolone, P Paul, D Payne, GF Pearce, C Pearson, JD Perkin, M Pfleger, F Pierre, D Pierrepont, P Plonski, P Poffenberger, E Poplawska, B Popov, M Posiadala, J-M Poutissou, R Poutissou, R Preece, P Przewlocki, W Qian, JL Raaf, E Radicioni, K Ramos, P Ratoff, TM Raufer, M Ravonel, M Raymond, F Retiere, D Richards, J-L Ritou, A Robert, PA Rodrigues, E Rondio, M Roney, M Rooney, D Ross, B Rossi, S Roth, A Rubbia, D Ruterbories, R Sacco, S Sadler, K Sakashita, F Sanchez, A Sarrat, K Sasaki, P Schaack, J Schmidt, K Scholberg, J Schwehr, M Scott, DI Scully, Y Seiya, T Sekiguchi, H Sekiya, G Sheffer, M Shibata, Y Shimizu, M Shiozawa, S Short, M Siyad, D Smith, RJ Smith, M Smy, J Sobczyk, H Sobel, S Sooriyakumaran, M Sorel, J Spitz, A Stahl, P Stamoulis, O Star, J Statter, L Stawnyczy, J Steinmann, J Steffens, B Still, M Stodulski, J Stone, C Strabel, T Strauss, R Sulej, P Sutcliffe, A Suzuki, K Suzuki, S Suzuki, SY Suzuki, Y Suzuki, Y Suzuki, J Swierblewski, T Szeglowski, M Szeptycka, R Tacik, M Tada, AS Tadepalli, M Taguchi, S Takahashi, A Takeda, Y Takenaga, Y Takeuchi, HA Tanaka, K Tanaka, M Tanaka, MM Tanaka, N Tanimoto, K Tashiro, IJ Taylor, A Terashima, D Terhorst, R Terri, LF Thompson, A Thorley, M Thorpe, W Toki, T Tomaru, Y Totsuka, C Touramanis, T Tsukamoto, V Tvaskis, M Tzanov, Y Uchida, K Ueno, M Usseglio, A Vacheret, M Vagins, JF Van Schalkwyk, J-C Vanel, G Vasseur, O Veledar, P Vincent, T Wachala, AV Waldron, CW Walter, PJ Wanderer, MA Ward, GP Ward, D Wark, D Warner, MO Wascko, A Weber, R Wendell, J Wendland, N West, LH Whitehead, G Wikström, RJ Wilkes, MJ Wilking, Z Williamson, JR Wilson, RJ Wilson, K Wong, T Wongjirad, S Yamada, Y Yamada, A Yamamoto, K Yamamoto, Y Yamanoi, H Yamaoka, C Yanagisawa, T Yano, S Yen, N Yershov, M Yokoyama, A Zalewska, J Zalipska, K Zaremba, M Ziembicki, ED Zimmerman, M Zito, J Zmuda

Top quark mass measurement using the template method at CDF

Physical Review D - Particles, Fields, Gravitation and Cosmology 83:11 (2011)

Authors:

T Aaltonen, B Alvarez 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 measurement of the top quark mass in the lepton+jets and dilepton channels of tt̄ decays using the data sample corresponding to an integrated luminosity of 5.6fb-1 of pp̄ collisions at Tevatron with √s=1.96TeV, collected with the CDF II detector. We construct templates of two reconstructed top quark masses from different jets-to-quarks combinations and the invariant mass of two jets from the W decays in the lepton+jets channel, and a reconstructed top quark mass and mT2, a variable related to the transverse mass in events with two missing particles, in the dilepton channel. The simultaneous fit of the templates from signal and background events in the lepton+jets and dilepton channels to the data yields a measured top quark mass of Mtop=172.1±1.1(stat)±0. 9(syst)GeV/c2. © 2011 American Physical Society.