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Search for Excited and Exotic Electrons in the e-gamma Decay Channel in p-pbar Collisions at sqrt(s) = 1.96 TeV

D. Acosta
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Abstract

We present a search for excited and exotic electrons (e*) decaying to an electron and a photon, both with high transverse momentum. We use 202/pb of data collected in p-pbar collisions at sqrt(s) = 1.96 TeV with the CDF II detector. No signal above Standard Model expectation is seen for associated ee* production. We discuss the e* sensitivity in the parameter space of the excited electron mass M(e*) and the compositeness energy scale Lambda. In the contact interaction model, we exclude 132 < M(e*) < 879 GeV/c^2 for Lambda = M(e*) at 95% confidence level (C.L.). In the gauge-mediated model, we exclude 126 < M(e*) < 430 GeV/c^2 at 95% C.L. for the phenomenological coupling f/Lambda ~ 0.01/GeV.

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D. Acosta. 2005-02-21. Search for Excited and Exotic Electrons in the e-gamma Decay Channel in p-pbar Collisions at sqrt(s) = 1.96 TeV. https://doi.org/10.1103/physrevlett.94.101802

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