News & Events
Shailaja Mohanty (Queen’s University)
Event Details
McDonald Institute Seminar Series
Location: Queen's: STI 501 / YouTube
Date: February 5, 2026
Time: 12:30pm - 1:30pm
Latest Results from KATRIN on Neutrino Mass and Light Sterile Neutrinos
Abstract:
Neutrinos are known to have non-zero masses, as implied by oscillation observations, but their absolute mass scale remains unknown. While cosmological data and neutrinoless double beta decay experiments suggest sub-eV upper limits, the Karlsruhe Tritium Neutrino (KATRIN) experiment provides the most stringent model-independent upper bound, with a target sensitivity better than 0.3 eV.
By combining a high-intensity gaseous tritium source with high-resolution spectroscopy of the molecular tritium beta-decay spectrum, KATRIN has set an upper limit on the neutrino mass of 0.45 eV/c² (90% CL).
KATRIN also investigates the possibility of eV-scale sterile neutrinos, complementing short-baseline neutrino oscillation experiments, by searching for distortions in the β-spectrum caused by active-sterile neutrino mixing. New constraints within a minimal 3+1 sterile neutrino framework exclude significant regions of parameter space, particularly those motivated by short-baseline neutrino oscillation anomalies.
These results complement reactor-based oscillation experiments such as STEREO and PROSPECT, disfavoring regions of parameter space previously supported by global oscillation fits and excluding the parameter space favored by the Neutrino-4 experiment. This talk presents the latest results from the KATRIN experiment based on a 259-day data set.
The McDonald Institute seminar will be held in Stirling 501 and streamed live to the McDonald Institute YouTube channel.
A Zoom link is also available and shared via email by the organizers. Please reach out to admin@mcdonaldinstitute.ca for access.