Nuclei, neutrinos, and microwaves: searching for the neutrino mass in tritium decay
When Enrico Fermi published his theory of beta decay in 1934—what we now call the weak interaction—he suggested how experiments could measure the neutrino mass: by looking at the shape of the energy distribution of beta decay electrons. We’re still doing exactly that! I will talk about the state of the art of tritium beta decay electron measurements: the KATRIN experiment, which starts science runs soon with a molecular tritium source towards sub-0.3 eV sensitivity; and the Project 8 experiment, which aims to develop a future atomic tritium experiment sensitive to neutrino masses below 0.05 eV. Project 8 uses radio-telescope-like instrumentation to monitor single electron radiation fields; I will show exciting new data from our early phases, and vague cartoony sketches of our future large atomic experiment.