Mapping the material in the LHCb vertex locator using secondary hadronic interactions

M. Alexander, W. Barter, A. Bay, L. J. Bel, M. Van Beuzekom, G. Bogdanova, S. Borghi, T. J.V. Bowcock, E. Buchanan, J. Buytaert, K. Carvalho Akiba, S. Chen, V. Coco, P. Collins, A. Crocombe, F. Da Cunha Marinho, E. Dall'Occo, S. De Capua, C. T. Dean, F. DettoriD. Dossett, K. Dreimanis, G. Dujany, L. Eklund, T. Evans, M. Ferro-Luzzi, M. Gersabeck, T. Gershon, T. Hadavizadeh, J. Harrison, K. Hennessy, W. Hulsbergen, D. Hutchcroft, P. Ilten, E. Jans, M. John, P. Kopciewicz, P. Koppenburg, G. Lafferty, T. Latham, A. Leflat, M. W. Majewski, R. McNulty, J. Mylroie-Smith, A. Oblakowska-Mucha, C. Parkes, A. Pearce, A. Poluektov, A. Pritchard, W. Qian, S. Redford, S. Richards, K. Rinnert, E. Rodrigues, G. Sarpis, M. Schiller, H. Schindler, M. Smith, N. A. Smith, T. Szumlak, J. J. Velthuis, V. Volkov, C. Wallace, H. M. Wark, A. Webber, M. R.J. Williams, M. Williams

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22 Citations (Scopus)


Precise knowledge of the location of the material in the LHCb vertex locator (VELO) is essential to reducing background in searches for long-lived exotic particles, and in identifying jets that originate from beauty and charm quarks. Secondary interactions of hadrons produced in beam-gas collisions are used to map the location of material in the VELO. Using this material map, along with properties of a reconstructed secondary vertex and its constituent tracks, a p-value can be assigned to the hypothesis that the secondary vertex originates from a material interaction. A validation of this procedure is presented using photon conversions to dimuons.

Original languageEnglish
Article numberP06008
Number of pages13
JournalJournal of Instrumentation
Issue number6
Publication statusPublished - 13 Jun 2018
Externally publishedYes


  • Particle tracking detectors
  • Performance of High Energy Physics Detectors

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