Central Exclusive Production at LHCb

Authors

  • C. Van Hulse University College Dublin

DOI:

https://doi.org/10.15407/ujpe64.7.595

Keywords:

exclusive photoproduction, ultra-peripheral collisions, generalised parton distributions, parton distribution functions

Abstract

The LHCb collaboration has measured central exclusive production of J/ф, ф(2S), and ϒ mesons as well as J/фJ/ф, J/фф(2S), ф(2S)ф(2S), and xcxc meson pairs in proton-proton collisions. The analyses of ϒ and charmonium pairs are performed at the centre-of-mass energies of 7 TeV and 8 TeV, and those of J/ф and ф(2S) are done at 7 TeV and 13 TeV. The analysis at 13 TeV involves the use of new shower counters. These allow a reduction in the background by vetoing events with activity in an extended region in rapidity. The measurements of central exclusive production at LHCb are sensitive to gluon distributions for Bjorken-x values down to 2×10−6 (at 13 TeV). An overview of the LHCb results is presented and compared to existing measurements of other experiments and theoretical calculations.

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Published

2019-09-17

How to Cite

Van Hulse, C. (2019). Central Exclusive Production at LHCb. Ukrainian Journal of Physics, 64(7), 595. https://doi.org/10.15407/ujpe64.7.595

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