Overview

• The KATRIN experiment has established the most precise upper limit on neutrino mass to date, capping it at 0.45 electron volts (eV).
• This new limit, achieved through tritium decay analysis, is nearly half of the previous upper mass limit reported in 2022.
• Researchers analyzed data from 36 million electrons over 259 days, making this the most robust laboratory-based measurement of neutrino mass.
• The findings are independent of cosmological assumptions, providing a direct, lab-based constraint on neutrino mass.
• The experiment will continue collecting data through the end of 2025, with hopes of further refining the mass limit to 0.3 eV.