Search for excited fermions with the H1 detector

Abstract We present a search for excited electrons, neutrinos and quarks using the H1 detector at the ep collider HERA, based on data taken in 1994 with an integrated luminosity of 2.75 pb −1 . Radiative decays of excited quarks and neutrinos have been investigated as well as decays of excited electrons into all possible electroweak gauge bosons. No evidence for new particle production is found and exclusion limits are derived.