A search for forbidden and exotic Z boson decays in the diphoton mass spectrum is presented for the first time in hadron collisions, based on data corresponding to 10.0fb-1 of integrated luminosity from proton-antiproton collisions at s=1.96TeV collected by the CDF experiment. No evidence of signal is observed, and 95% credibility level Bayesian upper limits are set on the branching ratios of decays of the Z boson to a photon and neutral pion (which is detected as a photon), a pair of photons, and a pair of neutral pions. The observed branching ratio limits are 2.01×10-5 for Z→π0γ, 1.46×10-5 for Z→γγ, and 1.52×10-5 for Z→π0π0. The Z→π0γ and Z→γγ limits improve the most stringent results from other experiments by factors of 2.6 and 3.6, respectively. The Z→π0π0 branching ratio limit is the first experimental result on this decay. © 2014 American Physical Society.

First search for exotic Z boson decays into photons and neutral pions in hadron collisions

Cho K.;Corbo M.;Cordelli M.;Di Canto A.;Donati S.;Driutti A.;Glenzinski D.;Iori M.;Kondo K.;Leo S.;Liu H.;Marino P.;Moggi N.;Morello M. J.;Muller T.;Pauletta G.;Punzi G.;Ristori L.;Rodriguez T.;Ruffini F.;Rusu V.;Scuri F.;Tokar S.;Totaro P.;Vernieri C.;Vogel M.;Zhou C.;
2014-01-01

Abstract

A search for forbidden and exotic Z boson decays in the diphoton mass spectrum is presented for the first time in hadron collisions, based on data corresponding to 10.0fb-1 of integrated luminosity from proton-antiproton collisions at s=1.96TeV collected by the CDF experiment. No evidence of signal is observed, and 95% credibility level Bayesian upper limits are set on the branching ratios of decays of the Z boson to a photon and neutral pion (which is detected as a photon), a pair of photons, and a pair of neutral pions. The observed branching ratio limits are 2.01×10-5 for Z→π0γ, 1.46×10-5 for Z→γγ, and 1.52×10-5 for Z→π0π0. The Z→π0γ and Z→γγ limits improve the most stringent results from other experiments by factors of 2.6 and 3.6, respectively. The Z→π0π0 branching ratio limit is the first experimental result on this decay. © 2014 American Physical Society.
2014
Aaltonen, T.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A.; Antos, J.; Apollinari, G.; Appel, J. A.; Arisawa, T.; Artikov, A.; Asaadi, J.; Ashma...espandi
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Utilizza questo identificativo per citare o creare un link a questo documento: https://hdl.handle.net/11568/1126841
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