Search for new phenomena in events with two \(Z\) bosons and missing transverse momentum in \(p\bar{p}\) collisions at \(\sqrt{s}=1.96\) TeV

• Published in: arXiv.org 2011-12
• Main Authors: Aaltonen, T, B Alvarez Gonzalez, Apresyan, A, Aurisano, A, Barbaro-Galtieri, A, Bartos, P, Bauce, M, Bocci, A, Calancha, C, Casarsa, M, Cauz, D, Chlachidze, G, Chou, J P, Corbo, M, de Barbaro, P, De Lorenzo, G, Deng, J, A Di Canto, D'Onofrio, M, Dorigo, M, Eusebi, R, Feindt, M, Giokaris, N, Giromini, P, Goldschmidt, N, Gomez-Ceballos, G, Goncharov, M, Happacher, F, Hare, D, Harr, R F, Heck, M, Hidas, D, Hopkins, W, Horn, D, Huston, J, Jha, M K, Jun, S Y, Kim, D H, Kim, H S, Kim, S B, Kirby, M, Konigsberg, J, Lammel, S, Lander, R L, Lee, H S, Lewis, J D, Liu, C, Lujan, P, Lysak, R, Makhoul, K, Manousakis-Katsikakis, A, Margaroli, F, Marino, C, McNulty, R, Menzione, A, Moggi, N, Morello, M J, Morlock, J, Naganoma, J, Napier, A, Neu, C, Neubauer, M S, Nodulman, L, Palencia, E, Papadimitriou, V, Paramonov, A A, Pauletta, G, Pellett, D E, Poprocki, S, Pursley, J, Redondo, I, Rimondi, F, Rogers, E, Rossi, M, Santi, L, Saveliev, V, Seiya, Y, Semenov, A, Shochet, M, Simonenko, A, Smith, J R, Squillacioti, P, R St Denis, Strologas, J, Takemasa, K, Tang, J, Thom, J, Torretta, D, Uozumi, S, Vellidis, C, Vilar, R, Vizan, J, Warburton, A, Whitehouse, B, Whiteson, D, Wolfe, H, Yamamoto, K, Yang, Y C, Yoh, J, Yoshida, T
• Format: Article
• Language: English
• Subjects: Antiparticles; Antiprotons; Bosons; Collisions; Confidence intervals; Leptons; Luminosity; Neutrinos; Particle decay; Particle physics; Supersymmetry; Transverse momentum
• ISSN: 2331-8422
• DOI: 10.48550/arxiv.1112.1577

We present a search for new phenomena in events with two reconstructed \(Z\) bosons and large missing transverse momentum, sensitive to processes \(p\bar{p}\rightarrow X_2X_2 \rightarrow Z Z X_1 X_1\), where \(X_2\) is an unstable particle decaying as \(X_2\rightarrow ZX_1\) and \(X_1\) is undetected. The particles \(X_1\) and \(X_2\) may be, among other possibilities, fourth generation neutrinos or supersymmetric particles. We study the final state in which one \(Z\) boson decays to two charged leptons and the second decays hadronically. In data corresponding to an integrated luminosity of 4.2 fb\(^{-1}\) from proton-antiproton collisions recorded by the CDF II detector at the Tevatron, with center-of-mass energy of 1.96 TeV, we find agreement between data and standard-model backgrounds. We calculate 95% confidence level upper limits on the cross section of the process \(p\bar{p}\rightarrow X_2X_2 \rightarrow Z Z X_1 X_1\) ranging from 50 fb to 1 pb, depending on the masses of \(X_1\) and \(X_2\).