Exclusive γγ → WW and Anomalous Quartic Gauge Couplings at CMS

Recent CMS results sensitive to quartic couplings of gauge bosons are discussed. Thesignatures investigated are exclusive and quasi-exclusive $\gamma\gamma \rightarrow WW$ scattering, and tri-boson production in the $WW\gamma$ and $WZ\gamma$ channels. In the $\gamma\gamma \rightarrow WW$ analysis two candidate events pass the selection criteria, consistent with the Standard Model expectation. No deviations from the Standard Model are observed in the high $p_{T}$ tails of either measurement, and the resulting limits on anomalous quartic gauge couplings are the most stringent to date.