The appearance and disappearance of the 17-keV neutrino

Abstract

It is a fact of life in empirical science that experiments often give discordant results. This is nowhere better illustrated than in the recent history of experiments concerning the existence of a heavy, 17-keV neutrino. The 17-keV neutrino was first "discovered" by Simpson in 1985. The initial replications of the experiment all gave negative results, and suggestions were made that attempted to explain Simpson's result using accepted physics, without the need for a heavy neutrino. Subsequent positive results by Simpson and others led to further investigation. Several of these later experiments found evidence supporting that claim, whereas others found no evidence for such a particle. Some theorists attempted to explain away the result, and others tried to explain it and to incorporate it within existing theory without the need for a new particle, or to look for the further implications of such a particle, or to propose a new theory that would incorporate the new particle. The question of the existence of such a heavy neutrino remained for several years. Recently, doubt has been cast on the two most convincing positive experimental results, and errors have been found in those experiments. In addition, recent, extremely sensitive experiments have found no evidence for the 17-keV neutrino. The consensus is that it does not exist. The discord has been resolved by a combination of finding errors in one set of experiments and a preponderance of evidence.

On the physics of massive neutrinos

“…The different involved m i produce kinks in the Kurie-plot where the size of the kinks is a measure for the corresponding mixing angle. This was discussed in connection with the now ruled out 17 keV -neutrino [19,20]. The search for an eV-neutrino near the endpoint region is complicated due to several effects [21,22].…”

“…In SO(10) B-L is not necessarily conserved opening the chance for Majorana mass terms as well. The breaking of SO(10) allows different schemes like SO(10) → SU(5) → SU(3) ⊗ SU(2) ⊗ U(1) (19) or into a left-right symmetric version after the Pati-Salam model [16]…”

The Use of Low Temperature Detectors for Direct Measurements of the Mass of the Electron Neutrino

“…This has been confirmed experimentally in [106] (see § 6.5). It can also be shown that (44) can be approximated by the expression…”

Constraints on the Active and Sterile Neutrino Masses from Beta-Ray Spectra: Past, Present and Future1

“…Their detailed account can be found in refs. [200], [201]. "The rise and fall of the 17 keV neutrino" was also briefly described in ref.…”