@Article{LHCbCollaborationAaij_etal2024,
author="LHCb Collaboration (Aaij, R. et al
and Jaimes Elles, S. J.
and Jashal, B. K.
and Martinez-Vidal, F.
and Oyanguren, A.
and Rebollo De Miguel, M.
and Sanderswood, I.
and Zhuo, J.",
title="Measurement of J/$\psi$-pair production in pp collisions at {\textsurd}s=13 TeV and study of gluon transverse-momentum dependent PDFs",
journal="Journal of High Energy Physics",
year="2024",
publisher="Springer",
volume="03",
number="3",
pages="088--40pp",
optkeywords="Hadron-Hadron Scattering; Multi-Parton Interactions; QCD; Quarkonium",
abstract="The production cross-section of J/psi pairs in proton-proton collisions at a centre-of-mass energy of root s = 13TeV is measured using a data sample corresponding to an integrated luminosity of 4.2 fb(-1) collected by the LHCb experiment. The measurement is performed with both J/psi mesons in the transverse momentum range 0 < p(T) < 14 GeV/c and rapidity range 2.0 < y < 4.5. The cross-section of this process is measured to be 16.36 +/- 0.28 (stat) +/- 0.88 (syst) nb. The contributions from single-parton scattering and double-parton scattering are separated based on the dependence of the cross-section on the absolute rapidity difference Delta y between the two J/psi mesons. The effective cross-section of double-parton scattering is measured to be sigma(eff) = 13.1 +/- 1.8 (stat) +/- 2.3 (syst) mb. The distribution of the azimuthal angle phi(CS) of one of the J/psi mesons in the Collins-Soper frame and the p(T)-spectrum of the J/psi pairs are also measured for the study of the gluon transverse-momentum dependent distributions inside protons. The extracted values of < cos4 phi(CS)> and < cos2 phi(CS)> are consistent with zero, but the presence of azimuthal asymmetry at a few percent level is allowed.",
optnote="WOS:001194594600001",
optnote="exported from refbase (https://references.ific.uv.es/refbase/show.php?record=6050), last updated on Sun, 14 Apr 2024 09:40:51 +0000",
issn="1029-8479",
doi="10.1007/JHEP03(2024)088",
opturl="https://arxiv.org/abs/2311.14085",
opturl="https://doi.org/10.1007/JHEP03(2024)088",
language="English"
}