Search for excited quarks in ep collisions at HERA


Aaron F., Alexa C., Alimujiang K., Andreev V., Antunovic B., Asmone A., ...Daha Fazla

Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics, cilt.678, sa.4, ss.335-343, 2009 (SCI-Expanded) identifier identifier

Özet

A search for excited quarks is performed using the full e ± p 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 γ, 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 / Λ 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. © 2009 Elsevier B.V.