Cherenkov radiation by neutrinos

Abstract

We discuss the Cherenkov process $\nu \to \nu \gamma$ in the presence of a homogeneous magnetic field. The neutrinos are taken to be massless with only standard-model couplings. The magnetic field fulfills the dual purpose of inducing an effective neutrino-photon vertex and of modifying the photon dispersion relation such that the Cherenkov condition $\omega <|\mathbf{k}|$ is fulfilled. For a field strength $B_{\mathrm{crit}}=m_e^2/e=4.41\times 10^{13}Gauss$ and for $E=2m_e$ the Cherenkov rate is about $6\times 10^{-11}{s}^{-1}$.

Comments: Talk given at 4th SFB-375 Ringberg Workshop on Neutrino Astrophysics Ringberg Castle, Tegernsee, Germany, 20-24 Oct 1997