Reconstruction of primary vertices at the ATLAS experiment in Run 1 proton–proton collisions at the LHC. / The ATLAS Collaboration.

In: European Physical Journal C: Particles and Fields, Vol. 77, 332, 05.2017, p. 1-35.

Research output: Contribution to journalArticle



  • The ATLAS Collaboration


This paper presents the method and performance of primary vertex reconstruction in proton–proton collision data recorded by the ATLAS experiment during Run 1 of the LHC. The studies presented focus on data taken during 2012 at a centre-of-mass energy of √s=8 TeV. The performance has been measured as a function of the number of interactions per bunch crossing over a wide range, from one to seventy. The measurement of the position and size of the luminous region and its use as a constraint to improve the primary vertex resolution are discussed. A longitudinal vertex position resolution of about 30μm is achieved for events with high multiplicity of reconstructed tracks. The transverse position resolution is better than 20μm and is dominated by the precision on the size of the luminous region. An analytical model is proposed to describe the primary vertex reconstruction efficiency as a function of the number of interactions per bunch crossing and of the longitudinal size of the luminous region. Agreement between the data and the predictions of this model is better than 3% up to seventy interactions per bunch crossing.
Original languageEnglish
Article number332
Pages (from-to)1-35
Number of pages35
JournalEuropean Physical Journal C: Particles and Fields
Early online date19 May 2017
Publication statusPublished - May 2017
This open access research output is licenced under a Creative Commons Attribution-NonCommercial-NoDerivs 3.0 Unported License.

ID: 28228256