A search for excited neutrinos in e - p collisions at HERA


Aaron F., Alexa C., Andreev V., Antunovic B., Aplin S., Asmone A., ...More

Physics Letters, Section B: Nuclear, Elementary Particle and High-Energy Physics, vol.663, no.5, pp.382-389, 2008 (SCI-Expanded, Scopus)

Abstract

A search for first generation excited neutrinos is performed using the full e - p data sample collected by the H1 experiment at HERA at a centre-of-mass energy of 319 GeV, corresponding to a total luminosity of 184 pb -1. The electroweak decays of excited neutrinos ν * → ν γ, ν * → ν Z and ν * → e W with subsequent hadronic or leptonic decays of the W and Z bosons are considered. No evidence for excited neutrino production is found. Mass dependent exclusion limits on ν * production cross sections and on the ratio of the coupling to the compositeness scale f / Λ are derived within gauge mediated models. A limit on f / Λ, independent of the relative couplings to the SU (2) and U (1) gauge bosons, is also determined. These limits extend the excluded region to higher masses than has been possible in previous excited neutrino searches. © 2008 Elsevier B.V. All rights reserved.