Measuring neutrino mass with radioactive ions in a storage ring

Abstract

We propose a method to measure the neutrino mass kinematically using beams of ions which undergo beta decay. The idea is to tune the ion beam momentum so that in most decays, the electron is forward moving with respect to the beam, and only in decays near the endpoint is the electron moving backwards. Then, by counting the backward moving electrons one can observe the effect of neutrino mass on the beta spectrum close to the endpoint. In order to reach sensitivities for m ν < 0.2 eV, it is necessary to control the ion momentum with a precision better than δp/p < 10 −5 , identify suitable nuclei with low Q-values (in the few to ten keV range), and one must be able to observe at least O(10 18 ) decays.

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

“…(22). Sensitivity to the neutrino mass at the 90 % CL predicted for the measurement of radioactive ions in a storage ring [166]. ( in the figure is identical with defined in Eq.…”

“…A possibility of measuring the neutrino mass with radioactive ions in a storage ring was explored by Lindroos et al [166]. This novel kinematic (and thus model-independent) approach requires a tuning of an ion beam that causes most of β-particles to move forward with respect to the beam while those from the endpoint region of the β-spectrum move backwards.…”