Measurement of Υ{hooked} production in pp collisions at √ s = 7TeV
European Physical Journal C 72:6 (2012) 1-12
Authors:
R Aaij, R Aaij, CA Beteta, CA Beteta, B Adeva, B Adeva, M Adinolfi, M Adinolfi, C Adrover, C Adrover, A Affolder, A Affolder, Z Ajaltouni, Z Ajaltouni, J Albrecht, J Albrecht, F Alessio, F Alessio, M Alexander, M Alexander, G Alkhazov, G Alkhazov, P Alvarez Cartelle, P Alvarez Cartelle, AA Alves, AA Alves, S Amato, S Amato, Y Amhis, Y Amhis, J Anderson, J Anderson, RB Appleby, RB Appleby, O Aquines Gutierrez, O Aquines Gutierrez, F Archilli, F Archilli, F Archilli, L Arrabito, L Arrabito, A Artamonov, A Artamonov, M Artuso, M Artuso, M Artuso, E Aslanides, E Aslanides, G Auriemma, G Auriemma, S Bachmann, S Bachmann, JJ Back, JJ Back, DS Bailey, DS Bailey, V Balagura, V Balagura, V Balagura, W Baldini, W Baldini, RJ Barlow, RJ Barlow, C Barschel, C Barschel, S Barsuk, S Barsuk, W Barter, W Barter, A Bates, A Bates, C Bauer, C Bauer, T Bauer, T Bauer, A Bay, A Bay, I Bediaga, I Bediaga, S Belogurov, S Belogurov, K Belous, K Belous, I Belyaev, I Belyaev, E Ben-Haim, E Ben-Haim, M Benayoun, M Benayoun, G Bencivenni, G Bencivenni, S Benson, S Benson, J Benton, J Benton, R Bernet, R Bernet, MO Bettler, MO Bettler, M van Beuzekom
Abstract:
The production of Υ{hooked}(1S), Υ{hooked}(2S) and Υ{hooked}(3S) mesons in proton-proton collisions at the centre-of-mass energy of √ s = 7TeV is studied with the LHCb detector. The analysis is based on a data sample of 25 pb
-1 collected at the Large Hadron Collider. The Υ{hooked} mesons are reconstructed in the decay mode Υ{hooked}→μ
+μ
- and the signal yields are extracted from a fit to the μ
+μ
- invariant mass distributions. The differential production cross-sections times dimuon branching fractions are measured as a function of the Υ{hooked} transverse momentum p
T and rapidity y, over the range p
T<15 GeV/c and 2. 0
Opposite-side flavour tagging of B mesons at the LHCb experiment
European Physical Journal C 72:6 (2012) 1-16
Authors:
R Aaij, R Aaij, CA Beteta, CA Beteta, B Adeva, B Adeva, M Adinolfi, M Adinolfi, C Adrover, C Adrover, A Affolder, A Affolder, Z Ajaltouni, Z Ajaltouni, J Albrecht, J Albrecht, F Alessio, F Alessio, M Alexander, M Alexander, G Alkhazov, G Alkhazov, PA Cartelle, PA Cartelle, AA Alves, AA Alves, S Amato, S Amato, Y Amhis, Y Amhis, J Anderson, J Anderson, RB Appleby, RB Appleby, OA Gutierrez, OA Gutierrez, F Archilli, F Archilli, F Archilli, L Arrabito, L Arrabito, A Artamonov, A Artamonov, M Artuso, M Artuso, M Artuso, E Aslanides, E Aslanides, G Auriemma, G Auriemma, S Bachmann, S Bachmann, JJ Back, JJ Back, DS Bailey, DS Bailey, V Balagura, V Balagura, V Balagura, W Baldini, W Baldini, RJ Barlow, RJ Barlow, C Barschel, C Barschel, S Barsuk, S Barsuk, W Barter, W Barter, A Bates, A Bates, C Bauer, C Bauer, T Bauer, T Bauer, A Bay, A Bay, I Bediaga, I Bediaga, S Belogurov, S Belogurov, K Belous, K Belous, I Belyaev, I Belyaev, E Ben-Haim, E Ben-Haim, M Benayoun, M Benayoun, G Bencivenni, G Bencivenni, S Benson, S Benson, J Benton, J Benton, R Bernet, R Bernet, MO Bettler, MO Bettler, M van Beuzekom
Abstract:
The calibration and performance of the opposite-side flavour tagging algorithms used for the measurements of time-dependent asymmetries at the LHCb experiment are described. The algorithms have been developed using simulated events and optimized and calibrated with B+→J/ψK+, B0→J/ψK*0 and B0→D*-μ+νμ decay modes with 0. 37 fb-1 of data collected in pp collisions at s = 7 TeV during the 2011 physics run. The opposite-side tagging power is determined in the B+→J/ψK+ channel to be (2. 10±0. 08±0. 24) %, where the first uncertainty is statistical and the second is systematic. © 2012 CERN for the benefit of the LHCb collaboration.
Studies of the decays D0→KS0K-π+ and D0→KS0K+π-
Physical Review D - Particles, Fields, Gravitation and Cosmology 85:9 (2012)
Authors:
J Insler, H Muramatsu, CS Park, LJ Pearson, EH Thorndike, S Ricciardi, C Thomas, M Artuso, S Blusk, R Mountain, T Skwarnicki, S Stone, JC Wang, LM Zhang, G Bonvicini, D Cinabro, MJ Smith, P Zhou, T Gershon, P Naik, J Rademacker, KW Edwards, K Randrianarivony, RA Briere, H Vogel, PUE Onyisi, JL Rosner, JP Alexander, DG Cassel, S Das, R Ehrlich, L Gibbons, SW Gray, DL Hartill, DL Kreinick, VE Kuznetsov, JR Patterson, D Peterson, D Riley, A Ryd, AJ Sadoff, X Shi, WM Sun, J Yelton, P Rubin, N Lowrey, S Mehrabyan, M Selen, J Wiss, J Libby, M Kornicer, RE Mitchell, D Besson, TK Pedlar, D Cronin-Hennessy, J Hietala, S Dobbs, Z Metreveli, KK Seth, A Tomaradze, T Xiao, D Johnson, S Malde, L Martin, A Powell, G Wilkinson, DM Asner, G Tatishvili, JY Ge, DH Miller, IPJ Shipsey, B Xin, GS Adams, J Napolitano, KM Ecklund
Abstract:
The first measurements of the coherence factor RKS0Kπ and the average strong-phase difference δDKS0Kπ in D0→KS0K ∓π± decays are reported. These parameters can be used to improve the determination of the unitary triangle angle γ in B-→D∼K- decays, where D∼ is either a D0 or a D̄0 meson decaying to the same final state, and also in studies of charm mixing. The measurements of the coherence factor and strong-phase difference are made using quantum-correlated, fully reconstructed D0D̄0 pairs produced in e+e- collisions at the ψ(3770) resonance. The measured values are RKS0Kπ=0. 73±0.08 and δDKS0Kπ=(8.3±15.2)° for an unrestricted kinematic region and RK*K=1.00±0.16 and δDK *K=(26.5±15.8)° for a region where the combined KS0π± invariant mass is within 100MeV/c2 of the K *(892)± mass. These results indicate a significant level of coherence in the decay. In addition, isobar models are presented for the two decays, which show the dominance of the K *(892)± resonance. The branching ratio B(D0→KS0K+π-)/B(D0→KS0K -π+) is determined to be 0.592±0.044(stat) ±0.018(syst), which is more precise than previous measurements. © 2012 American Physical Society.
First Observation of the Decays B¯0 → D+K-π+π- and B- → D0K-π+π-
Physical Review Letters 108:16 (2012)
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, 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, S Belogurov, 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, T Bird, A Bizzeti, PM Bjørnstad, T Blake, F Blanc, C Blanks, J Blouw, S Blusk, A Bobrov, V Bocci, A Bondar, W Bonivento, N Bondar, S Borghi, A Borgia, TJV Bowcock, C Bozzi, T Brambach, J Van Den Brand, J Bressieux, D Brett, M Britsch, T Britton, NH Brook, H Brown, A Büchler-Germann, I Burducea, A Bursche, J Buytaert, S Cadeddu, 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, C Cauet, M Charles, P Charpentier, N Chiapolini, K Ciba, X Cid Vidal
Abstract:
First observations of the Cabibbo-suppressed decays B¯0 → D+K-π+π- and B- → D0K-π+π- are reported using 35 pB-1 of data collected with the LHCb detector. Their branching fractions are measured with respect to the corresponding Cabibbo-favored decays, from which we obtain B(B¯0→ D+K-π+π-)/B(B¯0→D+π-π+π-)=(5.9±1.1±0.5)×10-2 and B(B-→D0K-π+π-)/B(B-→ D0π-π+π-)=(9.4±1.3±0.9)×10-2, where the uncertainties are statistical and systematic, respectively. The B- → D0K-π+π- decay is particularly interesting, as it can be used in a similar way to B- → D0K- to measure the Cabibbo-Kobayashi-Maskawa phase γ. © 2012 CERN.
Observation of B̄s0→J/ψf2′(1525) in J/ψK +K - final states
Physical Review Letters 108:15 (2012)
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, 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, S Belogurov, 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, T Bird, 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, M Britsch, T Britton, NH Brook, H Brown, A Büchler-Germann, I Burducea, A Bursche, J Buytaert, S Cadeddu, 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, C Cauet, M Charles, P Charpentier, N Chiapolini, K Ciba, X Cid Vidal
Abstract:
The decay B̄s0→J/ψK +K - is investigated using 0.16fb -1 of data collected with the LHCb detector using 7 TeV pp collisions. Although the J/ψ channel is well known, final states at higher K +K - masses have not previously been studied. In the K +K - mass spectrum we observe a significant signal in the f2′(1525) region as well as a nonresonant component. After subtracting the nonresonant component, we find B(B̄s0→J/ψf2′(1525))/ B(B̄s0→J/ψ)=(26.4±2.7±2.4)%. © 2012 CERN.
