I am very happy to contribute to the celebration of Jose’s work and career in the field of Theoretical Neutrino Physics. In addition to writing many excellent papers on the subject he has built from scratch one of the largest groups in the world (containing students and visitors as well as permanent researchers) dedicated to this branch of physics. As a public service, the Valencia group also produces an important annual summary and analysis of the latest experimental results on the neutrino masses and mixing parameters.
To avoid overlapping others, I will just briefly discuss some work Jose and I did together at Syracuse, New York. By 1979, the charged lepton, tau was well established and people were thinking about its presumed neutrino partner. Jose and I discussed with Ted Kalogeropoulos, an experimentalist at Syracuse, the possibility of getting some experimental information on it. Ted pointed out it was conceivable to experimentally bound the existence or non-existence of a pi zero decaying into a (massive) tau neutrino and an anti tau neutrino. That is easily calculated in the standard weak interaction model and we wrote a paper on it [T. Kalogeropoulos et al,Phys Lett 86B, 72 (1979)]. This got us started thinking more seriously about neutrinos; it was fun, working together, to learn about the subject. We summarized what we had learned in a paper called “Neutrino masses in SU(2)xU(1) theories” [PRD 22, 2227 (1980)]. Then we used the results to study other aspects of the subject: “Neutrino oscillation thought experiment” [PRD 23, 1666(1981)],“Majorana neutrinos and magnetic fields” [PRD 24,1883(1981), “Neutrino decay and spontaneous violation of lepton number”[PRD 25, 774(1982)] and “Neutrinoless double beta decay in SU(2) x U(1) theories” [PRD, 2591 (1982)].
It seems appropriate to congratulate Jose and wish him (and the entire group) Happy Neutrinoing in the future.
June 19 2013