%0 Journal Article
%T Precision luminosity measurements at LHCb
%A LHCb Collaboration (Aaij, R. et al
%A Martinez-Vidal, F.
%A Oyanguren, A.
%A Ruiz Valls, P.
%A Sanchez Mayordomo, C.
%J Journal of Instrumentation
%D 2014
%V 9
%I Iop Publishing Ltd
%@ 1748-0221
%G English
%F LHCbCollaborationAaij_etal2014
%O WOS:000345859200021
%O exported from refbase (https://references.ific.uv.es/refbase/show.php?record=2030), last updated on Thu, 01 Jan 2015 13:50:21 +0000
%X Measuring cross-sections at the LHC requires the luminosity to be determined accurately at each centre-of-mass energy root s. In this paper results are reported from the luminosity calibrations carried out at the LHC interaction point 8 with the LHCb detector for root s = 2.76, 7 and 8TeV (proton-proton collisions) and for root s(NN) = 5TeV (proton-lead collisions). Both the "van der Meer scan" and "beam-gas imaging" luminosity calibration methods were employed. It is observed that the beam density profile cannot always be described by a function that is factorizable in the two transverse coordinates. The introduction of a two-dimensional description of the beams improves significantly the consistency of the results. For proton-proton interactions at root s = 8TeV a relative precision of the luminosity calibration of 1.47% is obtained using van der Meer scans and 1.43% using beam-gas imaging, resulting in a combined precision of 1.12%. Applying the calibration to the full data set determines the luminosity with a precision of 1.16%. This represents the most precise luminosity measurement achieved so far at a bunched-beam hadron collider.
%K Pattern recognition
%K cluster finding
%K calibration and fitting methods
%K Instrumentation for particle accelerators and storage rings – high energy (linear accelerators
%K synchrotrons)
%R 10.1088/1748-0221/9/12/P12005
%U http://arxiv.org/abs/1410.0149
%U https://doi.org/10.1088/1748-0221/9/12/P12005
%P P12005 - 91pp