Gallium neutrino absorption cross section and its uncertainty

Abstract

The ${}^{71}$Ga radiochemical experiments provided the first constraint on the flux of low-energy electron neutrinos coming from the Sun. Crucial neutrino calibration experiments, however, using intense $\ensuremath{\beta}$-decay sources, yielded rates below that predicted by theory. A recent effort to check the ``gallium anomaly'' using a more intense source exacerbated the discrepancy. This paper carefully reexamines the nuclear physics of neutrino absorption on ${}^{71}$Ga, slightly reducing but not eliminating the puzzling anomaly.

Topics & Concepts