Dr. Karolos Potamianos: Publications

Higgs boson studies at the Tevatron

Physical Review D - Particles, Fields, Gravitation and Cosmology 88:5 (2013)

Authors:

T Aaltonen, VM Abazov, B Abbott, BS Acharya, M Adams, T Adams, JP Agnew, GD Alexeev, G Alkhazov, A Alton, S Amerio, D Amidei, A Anastassov, A Annovi, J Antos, G Apollinari, JA Appel, T Arisawa, A Artikov, J Asaadi, W Ashmanskas, A Askew, S Atkins, B Auerbach, K Augsten, A Aurisano, C Avila, F Azfar, F Badaud, W Badgett, T Bae, L Bagby, B Baldin, DV Bandurin, S Banerjee, A Barbaro-Galtieri, E Barberis, P Baringer, VE Barnes, BA Barnett, P Barria, JF Bartlett, P Bartos, U Bassler, M Bauce, V Bazterra, A Bean, F Bedeschi, M Begalli, S Behari, L Bellantoni, G Bellettini, J Bellinger, D Benjamin, A Beretvas, SB Beri, G Bernardi, R Bernhard, I Bertram, M Besançon, R Beuselinck, PC Bhat, S Bhatia, V Bhatnagar, A Bhatti, KR Bland, G Blazey, S Blessing, K Bloom, B Blumenfeld, A Bocci, A Bodek, A Boehnlein, D Boline, EE Boos, G Borissov, D Bortoletto, J Boudreau, A Boveia, A Brandt, O Brandt, L Brigliadori, R Brock, C Bromberg, A Bross, D Brown, E Brucken, J Budagov, XB Bu, HS Budd, M Buehler, V Buescher, V Bunichev, S Burdin, K Burkett, G Busetto, P Bussey, CP Buszello, P Butti, A Buzatu

Abstract:

We combine searches by the CDF and D0 Collaborations for the standard model Higgs boson with mass in the range 90-200 GeV/c2 produced in the gluon-gluon fusion, WH, ZH, tt̄H, and vector boson fusion processes, and decaying in the H→bb̄, H→W+W-, H→ZZ, H→τ+τ-, and H→γγ modes. The data correspond to integrated luminosities of up to 10 fb-1 and were collected at the Fermilab Tevatron in pp̄ collisions at √s=1.96 TeV. The searches are also interpreted in the context of fermiophobic and fourth generation models. We observe a significant excess of events in the mass range between 115 and 140 GeV/c2. The local significance corresponds to 3.0 standard deviations at mH=125 GeV/c2, consistent with the mass of the Higgs boson observed at the LHC, and we expect a local significance of 1.9 standard deviations. We separately combine searches for H→bb̄, H→W +W-, H→τ+τ-, and H→γγ. The observed signal strengths in all channels are consistent with the presence of a standard model Higgs boson with a mass of 125 GeV/c2. © 2013 American Physical Society.

Observation of D0-D0bar Mixing using the CDF II Detector

ArXiv 1309.4078 (2013)

Authors:

CDF Collaboration, T Aaltonen, S Amerio, D Amidei, A Anastassov, A Annovi, J Antos, G Apollinari, JA Appel, T Arisawa, A Artikov, J Asaadi, W Ashmanskas, B Auerbach, A Aurisano, F Azfar, W Badgett, T Bae, A Barbaro-Galtieri, VE Barnes, BA Barnett, P Barria, P Bartos, M Bauce, F Bedeschi, S Behari, G Bellettini, J Bellinger, D Benjamin, A Beretvas, A Bhatti, KR Bland, B Blumenfeld, A Bocci, A Bodek, D Bortoletto, J Boudreau, A Boveia, L Brigliadori, C Bromberg, E Brucken, J Budagov, HS Budd, K Burkett, G Busetto, P Bussey, P Butti, A Buzatu, A Calamba, S Camarda, M Campanelli, F Canelli, B Carls, D Carlsmith, R Carosi, S Carrillo, 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, K Cho, D Chokheli, A Clark, C Clarke, ME Convery, J Conway, M Corbo, M Cordelli, CA Cox, DJ Cox, M Cremonesi, D Cruz, J Cuevas, R Culbertson, N d'Ascenzo, M Datta, P de Barbaro, L Demortier, L Marchese, M Deninno, F Devoto, M D'Errico, A Di Canto, B Di Ruzza, JR Dittmann, M D'Onofrio, S Donati, M Dorigo, A Driutti, K Ebina, R Edgar, A Elagin, R Erbacher, S Errede, B Esham, S Farrington, JP Fernández Ramos, R Field, G Flanagan, R Forrest, M Franklin, JC Freeman, H Frisch, Y Funakoshi, C Galloni, AF Garfinkel, P Garosi, H Gerberich, E Gerchtein, S Giagu, V Giakoumopoulou, K Gibson, CM Ginsburg, N Giokaris, P Giromini, G Giurgiu, V Glagolev, D Glenzinski, M Gold, D Goldin, A Golossanov, G Gomez, G Gomez-Ceballos, M Goncharov, O González López, I Gorelov, AT Goshaw, K Goulianos, E Gramellini, S Grinstein, C Grosso-Pilcher, RC Group, J Guimaraes da Costa, SR Hahn, JY Han, F Happacher, K Hara, M Hare, RF Harr, T Harrington-Taber, K Hatakeyama, C Hays, J Heinrich, M Herndon, A Hocker, Z Hong, W Hopkins, S Hou, RE Hughes, U Husemann, M Hussein, J Huston, G Introzzi, M Iori, A Ivanov, E James, D Jang, B Jayatilaka, EJ Jeon, S Jindariani, M Jones, KK Joo, SY Jun, TR Junk, M Kambeitz, T Kamon, PE Karchin, A Kasmi, Y Kato, W Ketchum, J Keung, B Kilminster, DH Kim, HS Kim, JE Kim, MJ Kim, SB Kim, SH Kim, YK Kim, YJ Kim, N Kimura, M Kirby, K Knoepfel, K Kondo, DJ Kong, J Konigsberg, AV Kotwal, M Kreps, J Kroll, M Kruse, N Kulkarni, T Kuhr, M Kurata, AT Laasanen, S Lammel, M Lancaster, K Lannon, G Latino, HS Lee, JS Lee, S Leo, S Leone, JD Lewis, A Limosani, E Lipeles, A Lister, H Liu, Q Liu, T Liu, S Lockwitz, A Loginov, A Lucà, D Lucchesi, J Lueck, P Lujan, P Lukens, G Lungu, J Lys, R Lysak, R Madrak, P Maestro, S Malik, G Manca, A Manousakis-Katsikakis, F Margaroli, P Marino, M Martínez, K Matera, ME Mattson, A Mazzacane, P Mazzanti, R McNulty, A Mehta, P Mehtala, C Mesropian, T Miao, D Mietlicki, A Mitra, H Miyake, S Moed, N Moggi, CS Moon, R Moore, MJ Morello, A Mukherjee, Th Muller, P Murat, M Mussini, J Nachtman, Y Nagai, J Naganoma, I Nakano, A Napier, J Nett, C Neu, T Nigmanov, L Nodulman, SY Noh, O Norniella, L Oakes, SH Oh, YD Oh, I Oksuzian, T Okusawa, R Orava, L Ortolan, C Pagliarone, E Palencia, P Palni, V Papadimitriou, W Parker, G Pauletta, M Paulini, C Paus, TJ Phillips, G Piacentino, E Pianori, J Pilot, K Pitts, C Plager, L Pondrom, S Poprocki, K Potamianos, F Prokoshin, A Pranko, F Ptohos, G Punzi, N Ranjan, I Redondo Fernández, P Renton, M Rescigno, F Rimondi, L Ristori, A Robson, T Rodriguez, S Rolli, M Ronzani, R Roser, JL Rosner, F Ruffini, A Ruiz, J Russ, V Rusu, WK Sakumoto, Y Sakurai, L Santi, K Sato, V Saveliev, A Savoy-Navarro, P Schlabach, EE Schmidt, T Schwarz, L Scodellaro, F Scuri, S Seidel, Y Seiya, A Semenov, F Sforza, SZ Shalhout, T Shears, PF Shepard, M Shimojima, M Shochet, I Shreyber-Tecker, A Simonenko, K Sliwa, JR Smith, FD Snider, V Sorin, H Song, M Stancari, R St Denis, D Stentz, J Strologas, Y Sudo, A Sukhanov, I Suslov, K Takemasa, Y Takeuchi, J Tang, M Tecchio, PK Teng, J Thom, E Thomson, V Thukral, D Toback, S Tokar, K Tollefson, T Tomura, D Tonelli, S Torre, D Torretta, P Totaro, M Trovato, F Ukegawa, S Uozumi, F Vázquez, G Velev, C Vellidis, C Vernieri, M Vidal, R Vilar, J Vizán, M Vogel, G Volpi, P Wagner, R Wallny, SM Wang, D Waters, WC Wester, D Whiteson, AB Wicklund, S Wilbur, HH Williams, JS Wilson, P Wilson, BL Winer, P Wittich, S Wolbers, H Wolfe, T Wright, X Wu, Z Wu, K Yamamoto, D Yamato, T Yang, UK Yang, YC Yang, W-M Yao, GP Yeh, K Yi, J Yoh, K Yorita, T Yoshida, GB Yu, I Yu, AM Zanetti, Y Zeng, C Zhou, S Zucchelli

Abstract:

We measure the time dependence of the ratio of decay rates for D0 -> K+ pi- to the Cabibbo-favored decay D0 -> K- pi+. The charge conjugate decays are included. A signal of 3.3 x 10^4 D*+ -> pi+ D0, D0 -> K+ pi- decays is obtained with D0 proper decay times between 0.75 and 10 mean D0 lifetimes. The data were recorded with the CDF II detector at the Fermilab Tevatron and correspond to an integrated luminosity of 9.6 fb-1 for p-pbar collisions at sqrt(s) = 1.96 TeV. Assuming CP conservation, we search for D0-D0bar mixing and measure the mixing parameters to be R_D = (3.51 +/- 0.35) x 10^{-3}, y' = (4.3 +/- 4.3) x 10^{-3}, and x'^2 = (0.08 +/- 0.18) x 10^{-3}. We report Bayesian probability intervals in the x'^2 - y' plane and find that the significance of excluding the no-mixing hypothesis is equivalent to 6.1 Gaussian standard deviations, providing the second observation of D0-D0bar mixing from a single experiment.

Search for excited electrons and muons in √s=8 TeV proton-proton collisions with the ATLAS detector

New Journal of Physics 15 (2013)

Authors:

G Aad, T Abajyan, B Abbott, J Abdallah, S Abdel Khalek, O Abdinov, R Aben, B Abi, M Abolins, OS Abouzeid, H Abramowicz, H Abreu, Y Abulaiti, BS Acharya, L Adamczyk, DL Adams, TN Addy, J Adelman, S Adomeit, T Adye, S Aefsky, T Agatonovic-Jovin, JA Aguilar-Saavedra, M Agustoni, SP Ahlen, A Ahmad, F Ahmadov, M Ahsan, G Aielli, TPA Åkesson, G Akimoto, AV Akimov, MA Alam, J Albert, S Albrand, MJ Alconada Verzini, M Aleksa, IN Aleksandrov, F Alessandria, C Alexa, G Alexander, G Alexandre, T Alexopoulos, M Alhroob, M Aliev, G Alimonti, L Alio, J Alison, BMM Allbrooke, LJ Allison, PP Allport, SE Allwood-Spiers, J Almond, A Aloisio, R Alon, A Alonso, F Alonso, A Altheimer, B Alvarez Gonzalez, MG Alviggi, K Amako, Y Amaral Coutinho, C Amelung, VV Ammosov, SP Amor Dos Santos, A Amorim, S Amoroso, N Amram, C Anastopoulos, LS Ancu, N Andari, T Andeen, CF Anders, G Anders, KJ Anderson, A Andreazza, V Andrei, XS Anduaga, S Angelidakis, P Anger, A Angerami, F Anghinolfi, AV Anisenkov, N Anjos, A Annovi, A Antonaki, M Antonelli, A Antonov, J Antos, F Anulli, M Aoki, L Aperio Bella, R Apolle, G Arabidze, I Aracena, Y Arai, ATH Arce, S Arfaoui, JF Arguin, S Argyropoulos

Abstract:

The ATLAS detector at the Large Hadron Collider is used to search for excited electrons and excited muons in the channel pp → ℓℓ* → ℓℓγ, assuming that excited leptons are produced via contact interactions. The analysis is based on 13 fb-1 of pp collisions at a centre-of-mass energy of 8 TeV. No evidence for excited leptons is found, and a limit is set at the 95% credibility level on the cross section times branching ratio as a function of the excited-lepton mass mℓ*. For mℓ* 0.8 TeV, the respective upper limits on σB(ℓ* → ℓγ) are 0.75 and 0.90 fb for the e* and μ* searches. Limits on σB are converted into lower bounds on the compositeness scale Λ. In the special case where Λ = m ℓ*, excited-electron and excited-muon masses below 2.2 TeV are excluded. © CERN 2013.

A Direct Measurement of the Total Decay Width of the Top Quark

ArXiv 1308.405 (2013)

Authors:

CDF Collaboration, T Aaltonen, S Amerio, D Amidei, A Anastassov, A Annovi, J Antos, G Apollinari, JA Appel, T Arisawa, A Artikov, J Asaadi, W Ashmanskas, B Auerbach, A Aurisano, F Azfar, W Badgett, T Bae, A Barbaro-Galtieri, VE Barnes, BA Barnett, P Barria, P Bartos, M Bauce, F Bedeschi, S Behari, G Bellettini, J Bellinger, D Benjamin, A Beretvas, A Bhatti, KR Bland, B Blumenfeld, A Bocci, A Bodek, D Bortoletto, J Boudreau, A Boveia, L Brigliadori, C Bromberg, E Brucken, J Budagov, HS Budd, K Burkett, G Busetto, P Bussey, P Butti, A Buzatu, A Calamba, S Camarda, M Campanelli, F Canelli, B Carls, D Carlsmith, R Carosi, S Carrillo, 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, K Cho, D Chokheli, A Clark, C Clarke, ME Convery, J Conway, M Corbo, M Cordelli, CA Cox, DJ Cox, M Cremonesi, D Cruz, J Cuevas, R Culbertson, N d'Ascenzo, M Datta, P de Barbaro, L Demortier, L Marchese, M Deninno, F Devoto, M D'Errico, A Di Canto, B Di Ruzza, JR Dittmann, M D'Onofrio, S Donati, M Dorigo, A Driutti, K Ebina, R Edgar, A Elagin, R Erbacher, S Errede, B Esham, S Farrington, JP Fernández Ramos, R Field, G Flanagan, R Forrest, M Franklin, JC Freeman, H Frisch, Y Funakoshi, C Galloni, AF Garfinkel, P Garosi, H Gerberich, E Gerchtein, S Giagu, V Giakoumopoulou, K Gibson, CM Ginsburg, N Giokaris, P Giromini, G Giurgiu, V Glagolev, D Glenzinski, M Gold, D Goldin, A Golossanov, G Gomez, G Gomez-Ceballos, M Goncharov, O González López, I Gorelov, AT Goshaw, K Goulianos, E Gramellini, S Grinstein, C Grosso-Pilcher, RC Group, J Guimaraes da Costa, SR Hahn, JY Han, F Happacher, K Hara, M Hare, RF Harr, T Harrington-Taber, K Hatakeyama, C Hays, J Heinrich, M Herndon, A Hocker, Z Hong, W Hopkins, S Hou, RE Hughes, U Husemann, M Hussein, J Huston, G Introzzi, M Iori, A Ivanov, E James, D Jang, B Jayatilaka, EJ Jeon, S Jindariani, M Jones, KK Joo, SY Jun, TR Junk, M Kambeitz, T Kamon, PE Karchin, A Kasmi, Y Kato, W Ketchum, J Keung, B Kilminster, DH Kim, HS Kim, JE Kim, MJ Kim, SB Kim, SH Kim, YK Kim, YJ Kim, N Kimura, M Kirby, K Knoepfel, K Kondo, DJ Kong, J Konigsberg, AV Kotwal, M Kreps, J Kroll, M Kruse, T Kuhr, M Kurata, AT Laasanen, S Lammel, M Lancaster, K Lannon, G Latino, HS Lee, JS Lee, S Leo, S Leone, JD Lewis, A Limosani, E Lipeles, A Lister, H Liu, Q Liu, T Liu, S Lockwitz, A Loginov, A Lucà, D Lucchesi, J Lueck, P Lujan, P Lukens, G Lungu, J Lys, R Lysak, R Madrak, P Maestro, S Malik, G Manca, A Manousakis-Katsikakis, F Margaroli, P Marino, M Martínez, K Matera, ME Mattson, A Mazzacane, P Mazzanti, R McNulty, A Mehta, P Mehtala, C Mesropian, T Miao, D Mietlicki, A Mitra, H Miyake, S Moed, N Moggi, CS Moon, R Moore, MJ Morello, A Mukherjee, Th Muller, P Murat, M Mussini, J Nachtman, Y Nagai, J Naganoma, I Nakano, A Napier, J Nett, C Neu, T Nigmanov, L Nodulman, SY Noh, O Norniella, L Oakes, SH Oh, YD Oh, I Oksuzian, T Okusawa, R Orava, L Ortolan, C Pagliarone, E Palencia, P Palni, V Papadimitriou, W Parker, G Pauletta, M Paulini, C Paus, TJ Phillips, G Piacentino, E Pianori, J Pilot, K Pitts, C Plager, L Pondrom, S Poprocki, K Potamianos, F Prokoshin, A Pranko, F Ptohos, G Punzi, N Ranjan, I Redondo Fernández, P Renton, M Rescigno, F Rimondi, L Ristori, A Robson, T Rodriguez, S Rolli, M Ronzani, R Roser, JL Rosner, F Ruffini, A Ruiz, J Russ, V Rusu, WK Sakumoto, Y Sakurai, L Santi, K Sato, V Saveliev, A Savoy-Navarro, P Schlabach, EE Schmidt, T Schwarz, L Scodellaro, F Scuri, S Seidel, Y Seiya, A Semenov, F Sforza, SZ Shalhout, T Shears, PF Shepard, M Shimojima, M Shochet, I Shreyber-Tecker, A Simonenko, K Sliwa, JR Smith, FD Snider, V Sorin, H Song, M Stancari, R St Denis, D Stentz, J Strologas, Y Sudo, A Sukhanov, I Suslov, K Takemasa, Y Takeuchi, J Tang, M Tecchio, PK Teng, J Thom, E Thomson, V Thukral, D Toback, S Tokar, K Tollefson, T Tomura, D Tonelli, S Torre, D Torretta, P Totaro, M Trovato, F Ukegawa, S Uozumi, F Vázquez, G Velev, C Vellidis, C Vernieri, M Vidal, R Vilar, J Vizán, M Vogel, G Volpi, P Wagner, R Wallny, SM Wang, D Waters, WC Wester, D Whiteson, AB Wicklund, S Wilbur, HH Williams, JS Wilson, P Wilson, BL Winer, P Wittich, S Wolbers, H Wolfe, T Wright, X Wu, Z Wu, K Yamamoto, D Yamato, T Yang, UK Yang, YC Yang, W-M Yao, GP Yeh, K Yi, J Yoh, K Yorita, T Yoshida, GB Yu, I Yu, AM Zanetti, Y Zeng, C Zhou, S Zucchelli

Abstract:

We present a measurement of the total decay width of the top quark using events with top-antitop-quark pair candidates reconstructed in the final state with one charged lepton and four or more hadronic jets. We use the full Tevatron Run II data set of $\sqrt{s} = 1.96$ TeV proton-antiproton collisions recorded by the CDF II detector. The top-quark mass and the mass of the hadronically-decaying $W$ boson are reconstructed for each event and compared with distributions derived from simulated signal and background samples to extract the top-quark width (\gmt) and the energy scale of the calorimeter jets with {\it in-situ} calibration. For a top-quark mass $\mtop = \gevcc{172.5}$, we find $1.10<\gmt<\gev{4.05}$ at 68% confidence level, which is in agreement with the standard-model expectation of \gev{1.3} and is the most precise direct measurement of the top-quark width to date.

Evidence for a bottom baryon resonance Lambda_b* in CDF data

ArXiv 1308.176 (2013)

Authors:

CDF Collaboration, T Aaltonen, S Amerio, D Amidei, A Anastassov, A Annovi, J Antos, G Apollinari, JA Appel, T Arisawa, A Artikov, J Asaadi, W Ashmanskas, B Auerbach, A Aurisano, F Azfar, W Badgett, T Bae, A Barbaro-Galtieri, VE Barnes, BA Barnett, P Barria, P Bartos, M Bauce, F Bedeschi, S Behari, G Bellettini, J Bellinger, D Benjamin, A Beretvas, A Bhatti, KR Bland, B Blumenfeld, A Bocci, A Bodek, D Bortoletto, J Boudreau, A Boveia, L Brigliadori, C Bromberg, E Brucken, J Budagov, HS Budd, K Burkett, G Busetto, P Bussey, P Butti, A Buzatu, A Calamba, S Camarda, M Campanelli, F Canelli, B Carls, D Carlsmith, R Carosi, S Carrillo, 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, K Cho, D Chokheli, A Clark, C Clarke, ME Convery, J Conway, M Corbo, M Cordelli, CA Cox, DJ Cox, M Cremonesi, D Cruz, J Cuevas, R Culbertson, N d'Ascenzo, M Datta, P de Barbaro, L Demortier, L Marchese, M Deninno, F Devoto, M D'Errico, A Di Canto, B Di Ruzza, JR Dittmann, M D'Onofrio, S Donati, M Dorigo, A Driutti, K Ebina, R Edgar, A Elagin, R Erbacher, S Errede, B Esham, S Farrington, JP Fernández Ramos, R Field, G Flanagan, R Forrest, M Franklin, JC Freeman, H Frisch, Y Funakoshi, C Galloni, AF Garfinkel, P Garosi, H Gerberich, E Gerchtein, S Giagu, V Giakoumopoulou, K Gibson, CM Ginsburg, N Giokaris, P Giromini, G Giurgiu, V Glagolev, D Glenzinski, M Gold, D Goldin, A Golossanov, G Gomez, G Gomez-Ceballos, M Goncharov, O González López, I Gorelov, AT Goshaw, K Goulianos, E Gramellini, S Grinstein, C Grosso-Pilcher, RC Group, J Guimaraes da Costa, SR Hahn, JY Han, F Happacher, K Hara, M Hare, RF Harr, T Harrington-Taber, K Hatakeyama, C Hays, J Heinrich, M Herndon, A Hocker, Z Hong, W Hopkins, S Hou, RE Hughes, U Husemann, M Hussein, J Huston, G Introzzi, M Iori, A Ivanov, E James, D Jang, B Jayatilaka, EJ Jeon, S Jindariani, M Jones, KK Joo, SY Jun, TR Junk, M Kambeitz, T Kamon, PE Karchin, A Kasmi, Y Kato, W Ketchum, J Keung, B Kilminster, DH Kim, HS Kim, JE Kim, MJ Kim, SB Kim, SH Kim, YK Kim, YJ Kim, N Kimura, M Kirby, K Knoepfel, K Kondo, DJ Kong, J Konigsberg, AV Kotwal, M Kreps, J Kroll, M Kruse, T Kuhr, M Kurata, AT Laasanen, S Lammel, M Lancaster, K Lannon, G Latino, HS Lee, JS Lee, S Leo, S Leone, JD Lewis, A Limosani, E Lipeles, A Lister, H Liu, Q Liu, T Liu, S Lockwitz, A Loginov, A Lucà, D Lucchesi, J Lueck, P Lujan, P Lukens, G Lungu, J Lys, R Lysak, R Madrak, P Maestro, S Malik, G Manca, A Manousakis-Katsikakis, F Margaroli, P Marino, M Martínez, K Matera, ME Mattson, A Mazzacane, P Mazzanti, R McNulty, A Mehta, P Mehtala, C Mesropian, T Miao, D Mietlicki, A Mitra, H Miyake, S Moed, N Moggi, CS Moon, R Moore, MJ Morello, A Mukherjee, Th Muller, P Murat, M Mussini, J Nachtman, Y Nagai, J Naganoma, I Nakano, A Napier, J Nett, C Neu, T Nigmanov, L Nodulman, SY Noh, O Norniella, L Oakes, SH Oh, YD Oh, I Oksuzian, T Okusawa, R Orava, L Ortolan, C Pagliarone, E Palencia, P Palni, V Papadimitriou, W Parker, G Pauletta, M Paulini, C Paus, TJ Phillips, G Piacentino, E Pianori, J Pilot, K Pitts, C Plager, L Pondrom, S Poprocki, K Potamianos, F Prokoshin, A Pranko, F Ptohos, G Punzi, N Ranjan, I Redondo Fernández, P Renton, M Rescigno, F Rimondi, L Ristori, A Robson, T Rodriguez, S Rolli, M Ronzani, R Roser, JL Rosner, F Ruffini, A Ruiz, J Russ, V Rusu, WK Sakumoto, Y Sakurai, L Santi, K Sato, V Saveliev, A Savoy-Navarro, P Schlabach, EE Schmidt, T Schwarz, L Scodellaro, F Scuri, S Seidel, Y Seiya, A Semenov, F Sforza, SZ Shalhout, T Shears, PF Shepard, M Shimojima, M Shochet, I Shreyber-Tecker, A Simonenko, K Sliwa, JR Smith, FD Snider, V Sorin, H Song, M Stancari, R St Denis, D Stentz, J Strologas, Y Sudo, A Sukhanov, I Suslov, K Takemasa, Y Takeuchi, J Tang, M Tecchio, PK Teng, J Thom, E Thomson, V Thukral, D Toback, S Tokar, K Tollefson, T Tomura, D Tonelli, S Torre, D Torretta, P Totaro, M Trovato, F Ukegawa, S Uozumi, F Vázquez, G Velev, C Vellidis, C Vernieri, M Vidal, R Vilar, J Vizán, M Vogel, G Volpi, P Wagner, R Wallny, SM Wang, D Waters, WC Wester, D Whiteson, AB Wicklund, S Wilbur, HH Williams, JS Wilson, P Wilson, BL Winer, P Wittich, S Wolbers, H Wolfe, T Wright, X Wu, Z Wu, K Yamamoto, D Yamato, T Yang, UK Yang, YC Yang, W-M Yao, GP Yeh, K Yi, J Yoh, K Yorita, T Yoshida, GB Yu, I Yu, AM Zanetti, Y Zeng, C Zhou, S Zucchelli

Abstract:

Using data from proton-antiproton collisions at Ecms=1.96 TeV recorded by the CDF II detector at the Fermilab Tevatron, evidence for the excited resonance state Lambda_b* is presented in its Lambda_b0 pi+ pi- decay, followed by the Lambda_b0 -->Lambda_c+ (-->proton K- pi+) pi- decays. The analysis is based on a data sample corresponding to an integrated luminosity of 9.6/fb collected by an online event selection based on charged-particle tracks displaced from the proton-antiproton interaction point. The significance of the observed signal is 3.5 Gaussian sigmas. The mass of the observed state is found to be 5919.22 +- 0.76 MeV in agreement with similar findings in proton-proton collision experiments.

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