Physicists have been attempting to measure the mass of the neutrino since the first theoretical proposals by Enrico Fermi, with particular interest emerging since neutrino oscillations confirm that the masses are not zero. Current attempts to measure the neutrino mass require high-precision, high-throughput electron spectrometers to measure tritium beta decay, but known electrostatic techniques are reaching the end of their scalability. Here we show the first single-electron detection in a novel spectrometer. We detect single-electron cyclotron radiation emitted from mildly-relativistic electrons in a gaseous radioactive source. A relativistic shift in the cyclotron frequency provides a precise electron energy measurement, providing proof-of-concept for this technique's utility in future tritium neutrino mass searches. We will place the recent results in the context of various approaches aimed at measuring the mass of the neutrino.

Argonne Physics Division Seminar Schedule