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arXiv · 0904.3392

Search for Excited Quarks in ep Collisions at HERA

H1 Collaboration
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Abstract

A search for excited quarks is performed using the full ep data sample collected by the H1 experiment at HERA, corresponding to a total integrated luminosity of 475 pb^-1. The electroweak decays of excited quarks q* -> q gamma, q* -> q Z and q* -> q W with subsequent hadronic or leptonic decays of the W and Z bosons are considered. No evidence for first generation excited quark production is found. Mass dependent exclusion limits on q* production cross sections and on the ratio f/Lambda of the coupling to the compositeness scale are derived within gauge mediated models. These limits extend the excluded region compared to previous excited quark searches.

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H1 Collaboration. 2009-06-22. Search for Excited Quarks in ep Collisions at HERA. https://doi.org/10.1016/j.physletb.2009.06.044

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