Signals for Majorana neutrinos in a $\gamma \gamma$ collider

Abstract

We study the possibilities to detect Majorana neutrinos in $\gamma \gamma$ colliders for different center of mass energies. We study the $W^{\pm }{W}^{\pm }{l}_j^{\mp }{l}_k^{\mp }$ ($l_j\equiv e,\mu ,\tau$) final states which are, due to leptonic number violation, a clear signature for intermediate Majorana neutrino contribution. Such a signal (final dileptons of the same sign) is not possible if the heavy neutrinos are Dirac particles. We present our results for the total cross-section as a function of the neutrino mass and the center of mass energies.

Comments: 10 pages, 5 figures, Latex, to appear in Phys.Rev.D