Preprint number: CP3-Origins-2011-29 and DIAS-2011-16
The OPERA Collaboration reported evidence for muonic neutrinos traveling slightly faster than light in vacuum. While waiting further checks from the experimental community, here we aim at exploring some theoretical consequences of the hypothesis that muonic neutrinos are superluminal, considering in particular the tachyonic and the Coleman-Glashow cases. We show that a tachyonic interpretation is not only hardly reconciled with OPERA data on energy dependence, but that it clashes with neutrino production from pion and with neutrino oscillations. A Coleman-Glashow superluminal neutrino beam could instead be safely produced from pions and describe the OPERA data; it could also be easily reconciled with SN1987a data, but then it would be very problematic to account for neutrino oscillations.