The international KATRIN collaboration, which includes Marco Carminati, Carlo Fiorini and Urban Korbinian from the Department of Electronics, Information and Bioengineering – Politecnico di Milano, has achieved a new milestone, published in Nature.
After setting the record for the most precise direct measurement of the active neutrino mass, the experiment analysed data collected over 259 days, corresponding to 36 million electrons whose energy spectrum was measured. This extensive measurement campaign made it possible to exclude a wide range of values for the mass (up to 40 eV) and mixing angle of the sterile neutrino, a still-hypothetical particle that, if it exists, could represent a possible extension of the Standard Model.
An upgrade of the experimental apparatus is currently underway with the installation of the TRISTAN detector, which will enable KATRIN to investigate the full beta spectrum and search for sterile neutrinos in an even broader mass range, up to the keV scale.