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

• Published in: Journal of instrumentation 2018-06, Vol.13 (6), p.P06008-P06008
• Main Authors: Alexander, M., Barter, W., Bay, A., Bel, L.J., Beuzekom, M. van, Bogdanova, G., Borghi, S., Bowcock, T.J.V., Buchanan, E., Buytaert, J., Akiba, K. Carvalho, Chen, S., Coco, V., Collins, P., Crocombe, A., Marinho, F. Da Cunha, Dall'Occo, E., Capua, S. De, Dean, C.T., Dettori, F., Dossett, D., Dreimanis, K., Dujany, G., Eklund, L., Evans, T., Ferro-Luzzi, M., Gersabeck, M., Gershon, T., Hadavizadeh, T., Harrison, J., Hennessy, K., Hulsbergen, W., Hutchcroft, D., Ilten, P., Jans, E., John, M., Kopciewicz, P., Koppenburg, P., Lafferty, G., Latham, T., Leflat, A., Majewski, M.W., McNulty, R., Mylroie-Smith, J., Oblakowska-Mucha, A., Parkes, C., Pearce, A., Poluektov, A., Pritchard, A., Qian, W., Redford, S., Richards, S., Rinnert, K., Rodrigues, E., Sarpis, G., Schiller, M., Schindler, H., Smith, M., Smith, N.A., Szumlak, T., Velthuis, J.J., Volkov, V., Wallace, C., Wark, H.M., Webber, A., Williams, M.R.J., Williams, M.
• Format: Article
• Language: English
• Subjects: Charm (particle physics); Hadrons; High Energy Physics - Experiment; Instrumentation and Detectors; Mapping; Physics
• ISSN: 1748-0221; 1748-0221
• DOI: 10.1088/1748-0221/13/06/P06008

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.