First Search for Exotic Z Boson Decays into Photons and Neutral Pions in Hadron Collisions
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 10.0 fb[superscript −1] of integrated luminosity from proton-antiproton collisions at √s = 1.96 TeV collected by the CDF experiment. N...
| Main Authors: | , , |
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| Other Authors: | |
| Format: | Article |
| Language: | en_US |
| Published: |
American Physical Society
2014
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| Online Access: | http://hdl.handle.net/1721.1/88984 https://orcid.org/0000-0002-6047-4211 |
| Summary: | 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 10.0 fb[superscript −1] of integrated luminosity from proton-antiproton collisions at √s = 1.96 TeV 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[superscript −5] for Z → π[superscript 0]γ, 1.46 × 10[superscript −5] for Z → γγ, and 1.52 × 10[superscript −5] for Z → π[superscript 0]π[superscript 0]. The Z → π[superscript 0]γ and Z → γγ limits improve the most stringent results from other experiments by factors of 2.6 and 3.6, respectively. The Z → π[superscript 0]π[superscript 0] branching ratio limit is the first experimental result on this decay. |
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