Fifty Years of Neutrino Physics: A Few Episodes

Abstract

On the occasion of the 70th birthday of Edoardo Amaldi, about two years ago, I was invited to give a review talk on Neutrino Physics at the International Assembly of physicists, the major part of which was certainly not composed of neutrino physicists. Then the talk was much simpler than today, since you are all professional ``neutrinists''. Notice that I have only 30 minutes at my disposition (instead of 2 hours at the Amaldi Conference). I must avoid the danger of being trivial by telling you the a,b,c of your work. A way out of this difficulty, maybe, is to give a few recollections of such developments in neutrino physics which either are curious and at the same time very important (Pauli, Fermi) or about which I happen to be well informed for various reasons. Thus my talk will be entirely subjective (at a variance with the one I gave at the Amaldi celebration) and will be mainly dedicated to the young gene ration of neutrino investigators, who are well informed about today and yesterday developments, but not so well about old ones. I shall not talk about today problems, of course, since you are all here to discuss them during almost a week. By the way, most of you are used to thinking in terms of 10 5 -- 10 6 neutrino events and forgot, if you knew it, that 16 years after the Pauli neutrino hypothesis (1930) neutrinos were still considered as undetectable particles, and, as you heard today, they were first revealed in the free state only 25 years after they had been invented.