Abstract
A direct determination of the beta-spectrum of has been made in a high resolution magnetic spectrometer. The experimental data are fitted by a straight line Fermi plot from 5.5 kev to the maximum energy at 17.95±0.10 kev. An upper limit of 250 volts or 0.05 percent of the mass of the electron is obtained for the rest mass of the neutrino. New estimates are obtained for the comparative half-life, the neutron half-life, and the value of the Fermi universal constant of beta-decay.
- Received 23 June 1952
DOI:https://doi.org/10.1103/PhysRev.88.689
©1952 American Physical Society