Exclusive production of W pairs in CMS

We report the results on the search for exclusive production of $W$ pairs in the LHC with data collected by the Compact Muon Solenoid detector in proton-proton collisions at $\sqrt{s}$~=~7~TeV. The analysis comprises the two-photon production of a $W$ pairs, ${pp\to p\,W^{+}W^{-}\,p\to p\,\nu e^{\pm}\nu\mu^{\mp}\,p}$. Two events are observed in data for $p_{\textrm{\footnotesize T}}(\ell) > $~4~GeV, $-2.4 < \eta(\ell) < $~2.4 and $m(\mu^{\pm}e^{\mp}) > $~20~GeV, in agreement with the standard model prediction of 2.2~$\pm$~0.4 signal events with 0.84~$\pm$~0.15 background events. Moreover, a study of the tail of the lepton pair transverse momentum distribution is performed to search for an evidence of anomalous quartic gauge couplings in the $\gamma\gamma\to W^{+}W^{-}$ vertex. As no events are observed in data, it results in a model-independent upper limits for the anomalous quartic gauge couplings $a^{W}_{0,C}/\Lambda^{2}$, which are of the order of 10$^{-4}$.