Measurements of the $\mathrm{p}\mathrm{p}\to\mathrm{W}^{\pm}\gamma\gamma$ and $\mathrm{p}\mathrm{p}\to\mathrm{Z}\gamma\gamma$ cross sections and limits on anomalous quartic gauge couplings at $\sqrt{s} = 13~\mathrm{TeV}$

The cross section for $\mathrm{W}$ or $\mathrm{Z}$ boson production in association with two photons is measured in proton-proton collisions at a centre-of-mass energy of $13~\mathrm{TeV}$. The dataset corresponds to an integrated luminosity of $137~\mathrm{fb}^{-1}$ collected by the CMS experiment at the LHC. The $\mathrm{W}(\mathrm{l}\nu)\gamma\gamma$ and $\mathrm{Z}(\mathrm{l}\mathrm{l})\gamma\gamma$ (where $\mathrm{l}=\mathrm{e},\mu$) cross sections are extracted in the phase space identified by an electron (muon) transverse momentum threshold of $35~(30)~\mathrm{GeV}$ and a photon transverse momentum threshold of $20~\mathrm{GeV}$. The measured cross sections are $\sigma(\mathrm{W}\gamma\gamma) = 13.63 ^{+1.93}_{-1.89} \mathrm{(stat.)} ^{+4.04}_{-4.02} \mathrm{(syst.)} \pm 0.08 \mathrm{(PDF + scale)} \, \mathrm{fb}$ and $\sigma(\mathrm{Z}\gamma\gamma) = 5.41 ^{+0.58}_{-0.55} \mathrm{(stat.)} ^{+0.64}_{-0.70} \mathrm{(syst.)} \pm 0.06 \mathrm{(PDF + scale)} \, \mathrm{fb}$. Limits on anomalous quartic gauge couplings are set in the framework of an effective field theory with dimension-8 operators.