We present a search for new phenomena in events with two reconstructed Z bosons and large missing transverse momentum, sensitive to processes pp̄→X 2X 2→ZZX 1X 1, where X 2 is an unstable particle decaying as X 2→ 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 4.2fb -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 pp̄→X 2X 2→ZZX 1X 1 ranging from 50 fb to 1 pb, depending on the masses of X 1 and X 2. © 2012 American Physical Society.
Search for new phenomena in events with two Z bosons and missing transverse momentum in pp̄ collisions at √s=1.96TeV
Sforza F.;
2012-01-01
Abstract
We present a search for new phenomena in events with two reconstructed Z bosons and large missing transverse momentum, sensitive to processes pp̄→X 2X 2→ZZX 1X 1, where X 2 is an unstable particle decaying as X 2→ 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 4.2fb -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 pp̄→X 2X 2→ZZX 1X 1 ranging from 50 fb to 1 pb, depending on the masses of X 1 and X 2. © 2012 American Physical Society.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.