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Absolute luminosity measurements with the LHCb detector at the LHC

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LHCb Collaboration (Including: Back, J. J., Dossett, D., Gershon, T. J., Harrison, P. F., Kreps, Michal, Latham, Thomas, Pilar, T., Poluektov, Anton, Reid, Matthew M., Whitehead, M. (Mark) and Williams, M. P.). (2012) Absolute luminosity measurements with the LHCb detector at the LHC. Journal of Instrumentation, Volume 7 (Number 1). Article number P01010. ISSN 1748-0221

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Abstract

Absolute luminosity measurements are of general interest for colliding-beam experiments at storage rings. These measurements are necessary to determine the absolute cross-sections of reaction processes and are valuable to quantify the performance of the accelerator. Using data taken in 2010, LHCb has applied two methods to determine the absolute scale of its luminosity measurements for proton-proton collisions at the LHC with a centre-of-mass energy of 7 TeV. In addition to the classic ''van der Meer scan'' method a novel technique has been developed which makes use of direct imaging of the individual beams using beam-gas and beam-beam interactions. This beam imaging method is made possible by the high resolution of the LHCb vertex detector and the close proximity of the detector to the beams, and allows beam parameters such as positions, angles and widths to be determined. The results of the two methods have comparable precision and are in good agreement. Combining the two methods, an overal precision of 3.5% in the absolute luminosity determination is reached. The techniques used to transport the absolute luminosity calibration to the full 2010 data-taking period are presented.

Item Type: Journal Article
Subjects: Q Science > QC Physics
Divisions: Faculty of Science > Physics
Library of Congress Subject Headings (LCSH): Colliders (Nuclear physics), Proton-proton interactions, Large Hadron Collider (France and Switzerland)
Journal or Publication Title: Journal of Instrumentation
Publisher: IOP Publishing Ltd
ISSN: 1748-0221
Official Date: 10 January 2012
Dates:
DateEvent
10 January 2012Published
Volume: Volume 7
Number: Number 1
Article Number: Article number P01010
Identifier: 10.1088/1748-0221/7/01/P01010
Status: Peer Reviewed
Publication Status: Published
Access rights to Published version: Open Access
Funder: Brazil. Coordenação do Aperfeiçoamento de Pessoal de Nível Superior (CAPES), Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), Fundação Carlos Chagas Filho de Amparo à Pesquisa do Estado do Rio de Janeiro (FAPERJ), Financiadora de Estudos e Projetos (Brazil) (FINEP), European Organization for Nuclear Research (CERN), Guo jia zi ran ke xue ji jin wei yuan hui (China) [National Natural Science Foundation of China] (NSFC), Centre national de la recherche scientifique (France) (CNRS), Institut national de physique nucléaire et de physique des particules (IN2P3), Germany. Bundesministerium für Bildung und Forschung (BMBF), Deutsche Forschungsgemeinschaft (DFG), Hermann von Helmholtz-Gemeinschaft Deutscher Forschungszentren (HGF), Max-Planck-Gesellschaft zur Förderung der Wissenschaften [Max Planck Society for the Advancement of Science], Istituto nazionale di fisica nucleare (INFN), Science Foundation Ireland (SFI), Stichting voor Fundamenteel Onderzoek der Materie (FOM) [Foundation for Fundamental Research on Matter], Nederlandse Organisatie voor Wetenschappelijk Onderzoek [Netherlands Organisation for Scientific Research] (NWO), SCSR (Poland), Autoritatea Nationala pentru Cercetare Stiintifica (ANCS), Russia (Federation). Ministerstvo obrazovanii︠a︡ i nauki [Ministry of Education and Science], Federalʹnoe agentstvo po atomnoĭ ėnergii (Russia), Spain. Ministerio de Ciencia e Innovación (MICINN), Galicia (Spain : Region). Xunta, Catalonia (Spain), Schweizerischer Nationalfonds zur Förderung der Wissenschaftlichen Forschung [Swiss National Science Foundation] (SNSF), Switzerland. Staatssekretariat für Ausbildung und Forschung (SER), Nat︠s︡ionalʹna akademii︠a︡ nauk Ukraïny (NAS), Science and Technology Facilities Council (Great Britain) (STFC), National Science Foundation (U.S.) (NSF), Seventh Framework Programme (European Commission) (FP7), Auvergne (France)
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URI: http://wrap.warwick.ac.uk/id/eprint/47921

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