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Determination of the average lifetime of b-baryons

European Physical Journal C 71:1 (2011) 199-210

Authors:

P Abreu, W Adam, T Adye, E Agasi, I Ajinenko, R Aleksan, GD Alekseev, R Alemany, PP Allport, S Almehed, U Amaldi, S Amato, A Andreazza, ML Andrieux, P Antilogus, WD Apel, Y Arnoud, B Åsman, JE Augustin, A Augustinus, P Baillon, P Bambade, F Barao, R Barate, M Barbi, G Barbiellini, DY Bardin, A Baroncelli, O Barring, JA Barrio, W Bartl, MJ Bates, M Battaglia, M Baubillier, J Baudot, KH Becks, M Begalli, P Beilliere, Y Belokopytov, AC Benvenuti, M Berggren, D Bertrand, F Bianchi, M Bigi, MS Bilenky, P Billoir, D Bloch, M Blume, S Blyth, T Bolognese, M Bonesini, W Bonivento, PSL Booth, G Borisov, C Bosio, S Bosworth, O Botner, E Boudinov, B Bouquet, C Bourdarios, TJV Bowcock, M Bozzo, P Branchini, KD Brand, T Brenke, RA Brenner, C Bricman, L Brillault, RCA Brown, P Bruckman, JM Brunet, L Bugge, T Buran, T Burgsmueller, P Buschmann, A Buys, S Cabrera, M Caccia, M Calvi, AJ Camacho Rozas, T Camporesi, V Canale, M Canepa, K Cankocak, F Cao, F Carena, L Carroll, C Caso, CMV Gimenez, A Cattai, FR Cavallo, L Cerrito, V Chabaud, M Chapkin, P Charpentier, L Chaussard, J Chauveau, P Checchia, GA Chelkov, M Chen

Abstract:

The average lifetime of b-baryons has been studied using 3 × 106 hadronic Z0 decays collected by the DEL-PHI detector at LEP. Three methods have been used, based on the measurement of different observables: the proper decay time distribution of 206 vertices reconstructed with a A, a lepton and an oppositely charged pion; the impact parameter distribution of 441 muons with high transverse momentum accompanied by a A in the same jet; and the proper decay time distribution of 125 A0-lepton decay vertices with the A, exclusively reconstructed through its pKπ, pK0 and A3π decay modes. The combined result is:, where the first systematic error is due to experimental uncertainties and the second to the uncertainties in the modelling of the b-baryon production and semi-leptonic decay. Including the measurement recently published by DELPHI based on a sample of proton-muon vertices, the average b-baryon lifetime is T (b-baryon) = (1.255+0.115-0.102(stat)0102 ± 0.05) ps. © Springer-Verlag 1996.

Lifetime and mixing parameters of neutral D mesons and neutral B hadrons in experimental particle physics

Proceedings of the 6th International Workshop on the CKM Unitarity Triangle, CKM 2010 (2011)

Abstract:

A review of recent experimental measurements of the lifetime and mixing parameters of neutral D and B hadrons is presented. In particular, focus is given to measurements of D mixing and the ΛB lifetime.

First observation of the decay B̄s 0→D0K×0 and a measurement of the ratio of branching fractions B(B̄s 0→D0K×0) B(B̄0→D0ρ0)

Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 706:1 (2011) 32-39

Authors:

R Aaij, C Abellan Beteta, B Adeva, M Adinolfi, C Adrover, A Affolder, Z Ajaltouni, J Albrecht, F Alessio, M Alexander, G Alkhazov, P Alvarez Cartelle, AA Alves, S Amato, Y Amhis, J Anderson, RB Appleby, O Aquines Gutierrez, F Archilli, F Archilli, L Arrabito, A Artamonov, M Artuso, M Artuso, E Aslanides, G Auriemma, S Bachmann, JJ Back, DS Bailey, V Balagura, V Balagura, W Baldini, RJ Barlow, C Barschel, S Barsuk, W Barter, A Bates, C Bauer, T Bauer, A Bay, I Bediaga, K Belous, I Belyaev, I Belyaev, E Ben-Haim, M Benayoun, G Bencivenni, S Benson, J Benton, R Bernet, MO Bettler, M van Beuzekom, A Bien, S Bifani, A Bizzeti, PM Bjørnstad, T Blake, F Blanc, C Blanks, J Blouw, S Blusk, A Bobrov, V Bocci, A Bondar, N Bondar, W Bonivento, S Borghi, A Borgia, TJV Bowcock, C Bozzi, T Brambach, J van den Brand, J Bressieux, D Brett, S Brisbane, M Britsch, T Britton, NH Brook, H Brown, A Büchler-Germann, I Burducea, A Bursche, J Buytaert, S Cadeddu, JM Caicedo Carvajal, O Callot, M Calvi, M Calvo Gomez, A Camboni, P Campana, P Campana, A Carbone, G Carboni, R Cardinale, R Cardinale, A Cardini, L Carson, K Carvalho Akiba, G Casse, M Cattaneo

Abstract:

The first observation of the decay B̄s 0→D0K×0 using pp data collected by the LHCb detector at a centre-of-mass energy of 7 TeV, corresponding to an integrated luminosity of 36 pb-1, is reported. A signal of 34.4±6.8 events is obtained and the absence of signal is rejected with a statistical significance of more than nine standard deviations. The B̄s 0→D0K×0 branching fraction is measured relative to that of B̄0→D0 ρ0: B(B̄s 0→D0K×0) B(B̄0→D0ρ0)=1.48±0 .34±0.15±0.12, where the first uncertainty is statistical, the second systematic and the third is due to the uncertainty on the ratio of the B0 and Bs0 hadronisation fractions. © 2011 CERN.
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Search for high-mass resonances decaying into ZZ in p$\bar{p}$ collisions at $\sqrt{s}=1.96$\,TeV

ArXiv 1111.3432 (2011)

Authors:

CDF Collaboration, T Aaltonen, B Alvarez Gonzalez, 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, D Bisello, I Bizjak, 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, A Buzatu, A Calamba, 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, WH Chung, YS Chung, MA Ciocci, A Clark, C Clarke, G Compostella, ME Convery, J Conway, M Corbo, M Cordelli, CA Cox, DJ Cox, F Crescioli, J Cuevas, R Culbertson, D Dagenhart, N d'Ascenzo, M Datta, P de Barbaro, M Dell'Orso, L Demortier, M Deninno, F Devoto, M d'Errico, A Di Canto, B Di Ruzza, JR Dittmann, M D'Onofrio, S Donati, P Dong, M Dorigo, T Dorigo, K Ebina, A Elagin, A Eppig, R Erbacher, S Errede, N Ershaidat, R Eusebi, S Farrington, M Feindt, JP Fernandez, R Field, G Flanagan, R Forrest, MJ Frank, M Franklin, JC Freeman, Y Funakoshi, I Furic, M Gallinaro, JE Garcia, AF Garfinkel, P Garosi, H Gerberich, E Gerchtein, S Giagu, V Giakoumopoulou, P Giannetti, K Gibson, CM Ginsburg, N Giokaris, P Giromini, 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, S Grinstein, C Grosso-Pilcher, RC Group, J Guimaraes da Costa, 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, A Hocker, W Hopkins, D Horn, S Hou, RE Hughes, M Hurwitz, U Husemann, N Hussain, 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, T Kamon, PE Karchin, A Kasmi, Y Kato, W Ketchum, J Keung, V Khotilovich, B Kilminster, DH Kim, HS Kim, JE Kim, MJ Kim, SB Kim, SH Kim, YK Kim, YJ Kim, N Kimura, M Kirby, S Klimenko, K Knoepfel, K Kondo, DJ Kong, J Konigsberg, AV Kotwal, M Kreps, J Kroll, D Krop, M Kruse, V Krutelyov, T Kuhr, M Kurata, S Kwang, AT Laasanen, S Lami, S Lammel, M Lancaster, RL Lander, K Lannon, A Lath, G Latino, T LeCompte, E Lee, HS Lee, JS Lee, SW Lee, S Leo, S Leone, JD Lewis, A Limosani, C-J Lin, M Lindgren, E Lipeles, A Lister, DO Litvintsev, C Liu, H Liu, Q Liu, T Liu, S Lockwitz, A Loginov, D Lucchesi, J Lueck, P Lujan, P Lukens, G Lungu, J Lys, R Lysak, R Madrak, K Maeshima, P Maestro, S Malik, G Manca, A Manousakis-Katsikakis, F Margaroli, C Marino, M Martinez, P Mastrandrea, K Matera, ME Mattson, A Mazzacane, P Mazzanti, KS McFarland, P McIntyre, R McNulty, A Mehta, P Mehtala, C Mesropian, T Miao, D Mietlicki, A Mitra, H Miyake, S Moed, N Moggi, MN Mondragon, CS Moon, R Moore, MJ Morello, J Morlock, P Movilla Fernandez, A Mukherjee, Th Muller, P Murat, M Mussini, J Nachtman, Y Nagai, J Naganoma, I Nakano, A Napier, J Nett, C Neu, MS Neubauer, J Nielsen, L Nodulman, SY Noh, O Norniella, L Oakes, SH Oh, YD Oh, I Oksuzian, T Okusawa, R Orava, L Ortolan, S Pagan Griso, C Pagliarone, E Palencia, V Papadimitriou, AA Paramonov, J Patrick, G Pauletta, 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, F Prokoshin, A Pranko, F Ptohos, G Punzi, A Rahaman, V Ramakrishnan, N Ranjan, I Redondo, P Renton, M Rescigno, T Riddick, F Rimondi, L Ristori, A Robson, T Rodrigo, T Rodriguez, E Rogers, S Rolli, R Roser, F Ruffini, A Ruiz, J Russ, V Rusu, A Safonov, WK Sakumoto, Y Sakurai, L Santi, K Sato, V Saveliev, A Savoy-Navarro, P Schlabach, A Schmidt, EE Schmidt, T Schwarz, L Scodellaro, A Scribano, 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, P Sinervo, K Sliwa, JR Smith, FD Snider, A Soha, V Sorin, H Song, P Squillacioti, M Stancari, 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, D Toback, S Tokar, K Tollefson, T Tomura, D Tonelli, S Torre, D Torretta, P Totaro, M Trovato, F Ukegawa, S Uozumi, A Varganov, F Vazquez, G Velev, C Vellidis, M Vidal, I Vila, R Vilar, J Vizan, M Vogel, G Volpi, P Wagner, RL Wagner, T Wakisaka, R Wallny, SM Wang, A Warburton, D Waters, WC Wester III, D Whiteson, 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, 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, SS Yu, JC Yun, A Zanetti, Y Zeng, C Zhou, S Zucchelli

Abstract:

We search for high-mass resonances decaying into Z boson pairs using data corresponding to 6 fb^-1 collected by the CDF experiment in p\bar{p} collisions at sqrt{s}=1.96 TeV. The search is performed in three distinct final states: ZZ --> l^+l^-l^+l^-, ZZ --> l^+l^-\nu\nu, and ZZ --> l^+l^-jj. For a Randall-Sundrum graviton G*, the 95% CL upper limits on the production cross section times branching ratio to ZZ, sigma(p\bar{p} --> G^* --> ZZ), vary between 0.26 pb and 0.045 pb in the mass range 300 < M_{G*} < 1000 GeV/c^2.
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Determination of fs/fd for 7 TeV pp collisions and measurement of the B0→D-K+ branching fraction

Physical Review Letters 107:21 (2011)

Authors:

R Aaij, B Adeva, M Adinolfi, C Adrover, A Affolder, Z Ajaltouni, J Albrecht, F Alessio, M Alexander, G Alkhazov, P Alvarez Cartelle, AA Alves, S Amato, Y Amhis, J Amoraal, J Anderson, RB Appleby, O Aquines Gutierrez, L Arrabito, A Artamonov, M Artuso, E Aslanides, G Auriemma, S Bachmann, JJ Back, DS Bailey, V Balagura, W Baldini, RJ Barlow, C Barschel, S Barsuk, W Barter, A Bates, C Bauer, T Bauer, A Bay, I Bediaga, K Belous, I Belyaev, E Ben-Haim, M Benayoun, G Bencivenni, S Benson, J Benton, R Bernet, MO Bettler, M Van Beuzekom, A Bien, S Bifani, A Bizzeti, PM Bjørnstad, T Blake, F Blanc, C Blanks, J Blouw, S Blusk, A Bobrov, V Bocci, A Bondar, N Bondar, W Bonivento, S Borghi, A Borgia, TJV Bowcock, C Bozzi, T Brambach, J Van Den Brand, J Bressieux, S Brisbane, M Britsch, T Britton, NH Brook, A Büchler-Germann, A Bursche, J Buytaert, S Cadeddu, JM Caicedo Carvajal, O Callot, M Calvi, M Calvo Gomez, A Camboni, P Campana, A Carbone, G Carboni, R Cardinale, A Cardini, L Carson, K Carvalho Akiba, G Casse, M Cattaneo, M Charles, P Charpentier, N Chiapolini, X Cid Vidal, PEL Clarke, M Clemencic, HV Cliff, J Closier, C Coca, V Coco

Abstract:

The relative abundance of the three decay modes B0→D-K +, B0→D-π+, and Bs0→Ds- π+ produced in 7 TeV pp collisions at the LHC is determined from data corresponding to an integrated luminosity of 35pb-1. The branching fraction of B0→D-K+ is found to be B(B0→D-K+)=(2.01±0.18stat±0.14syst) ×10-4. The ratio of fragmentation fractions f s/fd is determined through the relative abundance of Bs0→Ds-π+ to B0→D-K+ and B0→D-π+, leading to fs/f d=0.253±0.017±0.017±0.020, where the uncertainties are statistical, systematic, and theoretical, respectively. © 2011 CERN.
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