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\ arXiv:2012.00895
Date: Tue, 1 Dec 2020 23:43:53 GMT (1206kb,D)

Title: Central exclusive production at LHCb
Authors: Charlotte Van Hulse (on behalf of the LHCb collaboration)
Categories: hep-ex
Comments: 6 pages, 5 figures, conference proceedings for New trends in
high-energy physics 2019 Journal-ref: Ukr. J. Phys. 64 (2019) 595-601
DOI: 10.15407/ujpe64.7.595
\ The LHCb collaboration has measured central exclusive production of $J/\psi$, $\psi(2S)$, and $\Upsilon$ mesons as well as $J/\psi J/\psi$, $J/\psi\psi(2S)$, $\psi(2S)\psi(2S)$, and $\chi_c\chi_c$ meson pairs in proton-proton collisions. The analyses of $\Upsilon$ and charmonium pairs are performed at the
centre-of-mass energies of 7 TeV and 8 TeV, and those of $J/\psi$ and
$\psi(2S)$ 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 $2\times10^{-6}$ (at 13 TeV). An
overview of the LHCb results is presented and compared to existing measurements
of other experiments and theoretical calculations.

\ ( https://arxiv.org/abs/2012.00895 , 1206kb)