Analysis of excited neutrinos at the CLIC
  We analyze the single and pair production of excited neutrinos at the CLIC through the processes $e^{+}e^{-}\rightarrow \nu^{*} \bar{\nu}$, $e^{+}e^{-} \rightarrow e^{+}\gamma^{*} e^{-} \rightarrow e^{+} \nu^{*} W^{-}$, and $e^{+}e^{-} \rightarrow e^{+}\gamma^{*} \gamma^{*} e^{-} \rightarrow e^{+} \nu^{*} \bar{\nu}^{*} e^{-}$ ($\gamma^{*}$ is the Weizsacker-Williams photon). We examine comprehensively the excited neutrino signal and corresponding backgrounds to obtain limits on excited neutrino mass for various values of the integrated luminosity and center-of-mass energy. We show that the obtained bounds are more restricted than current experimental bounds. 
M. K\"oksal
hep-ph