LHCb detector and performance

Proceedings of Science (2011)

Abstract:

The LHCb experiment at the CERN Large Hadron Collider (LHC) will measure the CKM parameters of the Unitarity Triangle with high precision, and is designed to discover physics beyond the Standard Model in rare heavy-flavour decays. The experiment is configured in the forward direction and covers a unique rapidity range at the LHC, 1.9 < & < 4.9. This paper describes the detector components of LHCb and the operating performances, focusing on the vertex locator, particle identification, calorimetry and muon system. In 2010, LHCb recorded a total of 37.7 pb-1 of data at √s = 7 TeV with a data-taking efficiency ofbetterthan90%. A selection of LHCb physics results will be shown, and the prospects for data taking in 2011 will be discussed. © Copyright owned by the author(s) under the terms of the Creative Commons Attribution-Non Commercial-Share Alike Licence.

Measurement of V0 production ratios in pp collisions at s√ = 0.9 and 7TeV

Journal of High Energy Physics 2011:8 (2011)

Authors:

R Aaij, B Adeva, M Adinolfi, C Adrover, A Affolder, Z Ajaltouni, J Albrecht, F Alessio, M Alexander, G Alkhazov, PA Cartelle, AA Alves, S Amato, Y Amhis, J Anderson, RB Appleby, OA 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, 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, A Büchler-Germann, I Burducea, A Bursche, J Buytaert, S Cadeddu, JMC Carvajal, O Callot, M Calvi, MC Gomez, A Camboni, P Campana, A Carbone, G Carboni, R Cardinale, A Cardini, L Carson, KC Akiba, G Casse, M Cattaneo, M Charles, P Charpentier, N Chiapolini, XC Vidal, G Ciezarek, PEL Clarke, M Clemencic, HV Cliff, J Closier, C Coca

Abstract:

The Ā/A and Ā/K0S production ratios are measured by the LHCb detector from 0.3 nb-1 of pp collisions delivered by the LHC at s√ = 0.9TeV and 1.8 nb-1 at s√ = 7TeV. Both ratios are presented as a function of transverse momentum, pT, and rapidity, y, in the ranges 0.15 < pT < 2.50GeV/c and 2.0 < y < 4.5. Results at the two energies are in good agreement as a function of rapidity loss, Δy = ybeam - y, and are consistent with previous measurements. The ratio Ā/A, measuring the transport of baryon number from the collision into the detector, is smaller in data than predicted in simulation, particularly at high rapidity. The ratio Ā/K0S , measuring the baryon-to-meson suppression in strange quark hadronisation, is significantly larger than expected.

Measurement of the inclusive Φ cross-section in pp collisions at s=7 TeV

Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 703:3 (2011) 267-273

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 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, TH 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, D Brett, 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 cross-section for inclusive Φ meson production in pp collisions at a centre-of-mass energy of s=7 TeV has been measured with the LHCb detector at the Large Hadron Collider. The differential cross-section is measured as a function of the Φ transverse momentum pT and rapidity y in the region 0.6

News from the flavour frontier - Heavy quark physics at the LHC

Proceedings of Science 2011-July (2011)

Abstract:

Results are presented on heavy flavour results from LHC data collected in 2010 and the early months of the 2011 run. All experiments have contributed to studies of heavy flavour production, where a wide range of measurements are now available. In the domain of heavy flavour decays there exist many observables which are highly sensitive to physics beyond the Standard Model. Here several benchmark analyses of LHCb already match or surpass in precision those of the B-factories and Tevatron. The other experiments, in particular CMS with its search for the rare decay B0s → μ+ μ-, are now augmenting this programme.

Search for the rare decays Bs0 → μ+μ- and B0 → μ+μ-

Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics 699:5 (2011) 330-340

Authors:

R Aaij, B Adeva, M Adinolfi, C Adrover, A Affolder, Z Ajaltouni, J Albrecht, F Alessio, M Alexander, P Alvarez Cartelle, AA Alves, S Amato, Y Amhis, J Amoraal, J Anderson, RB Appleby, O Aquines Gutierrez, L Arrabito, M Artuso, E Aslanides, G Auriemma, S Bachmann, DS Bailey, V Balagura, W Baldini, RJ Barlow, C Barschel, S Barsuk, A Bates, C Bauer, T Bauer, A Bay, I Bediaga, K Belous, I Belyaev, E Ben-Haim, M Benayoun, G Bencivenni, 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, E Bos, TJV Bowcock, C Bozzi, T Brambach, J van den Brand, J Bressieux, S Brisbane, M Britsch, T Britton, NH Brook, H Brown, 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, XC Vidal, PJ Clark, PEL Clarke, M Clemencic, HV Cliff, J Closier, C Coca, V Coco, J Cogan, P Collins, F Constantin

Abstract:

A search for the decays Bs0 → μ+μ- and B0 → μ+μ- is performed with about 37 pb-1 of pp collisions at s√=7 TeV collected by the LHCb experiment at the Large Hadron Collider at CERN. The observed numbers of events are consistent with the background expectations. The resulting upper limits on the branching ratios are B(Bs0 → μ+μ-)<5.6×10-8 and B(B0 → μ+μ-)<1.5×10-8 at 95% confidence level. © 2011 CERN.