Measurement of the W +W −γ cross section and direct limits on anomalous quartic gauge boson couplings at LEP

• Published in: Physics letters. B 2000-10, Vol.490 (3), p.187-195
• Main Authors: Alemanni, G., Anderhub, H., Bagnaia, P., Behner, F., Berdugo, J., Blyth, S.C., Bobbink, G.J., Boldizsar, L., Bourilkov, D., Bourquin, M., Branson, J.G., Burger, J.D., Cai, X.D., Carlino, G., Castellini, G., Cecchi, C., Chaturvedi, U.K., Chen, H.F., Civinini, C., Clare, I., Costantini, S., della Volpe, D., DeNotaristefani, F., El Mamouni, H., Engler, A., Fesefeldt, H., Forconi, G., Furetta, C., Gheordanescu, N., Grenier, G., Gruenewald, M.W., Guida, M., Gupta, V.K., Hebbeker, T., Hou, S.R., de Jong, P., Josa-Mutuberrı́a, I., Kim, D., Kittel, W., Kräber, M., Kunin, A., Lebrun, P., Leiste, R., Linde, F.L., Lista, L., Luckey, D., Lugnier, L., Luminari, L., Malgeri, L., Mangeol, D., Marzano, F., McNeil, R.R., Mele, S., von der Mey, M., Mirabelli, G., Muijs, A.J.M., Newman, H., Nisati, A., Pandoulas, D., Paoletti, S., Park, I.H., Pauss, F., Perret-Gallix, D., Pierella, F., Pieri, M., Piroué, P.A., Plyaskin, V., Pohl, M., Pothier, J., Prokofiev, D.O., Raics, P., Raja, N., Ramelli, R., Rancoita, P.G., Razis, P., Rodin, J., Romero, L., Salicio, J., Servoli, L., Shvorob, A., Spillantini, P., Stickland, D.P., Stone, A., Sultanov, G., Suter, H., Szillasi, Z., Sztaricskai, T., Tauscher, L., Tellili, B., Vicinanza, D., Violini, P., Vivargent, M., Vogel, H., Wadhwa, M., Weber, A., Wilkens, H., Wu, S.X., Xu, Z.Z., Yeh, S.C., Zilizi, G.
• Format: Article
• Language: English
• ISSN: 0370-2693; 1873-2445
• DOI: 10.1016/S0370-2693(00)00993-X

The process e +e −→W +W − γ is analysed using the data collected with the L3 detector at LEP at a centre-of-mass energy of 188.6 GeV , corresponding to an integrated luminosity of 176.8 pb −1. Based on a sample of 42 selected W +W − candidates containing an isolated hard photon, the W +W − γ cross section, defined within phase-space cuts, is measured to be: σ WW γ =290±80±16 fb, consistent with the Standard Model expectation. Including the process e +e − →ν ν ̄ γγ , limits are derived on anomalous contributions to the Standard Model quartic vertices W +W − γγ and W +W −Z γ at 95% CL: −0.043 GeV −2