Direct neutrino-mass measurement based on 259 days of KATRIN data.
basic_science · Level V
Where this comes from
- Record sourced from PubMed, PMID 40208982.
- Also identified by DOI 10.1126/science.adq9592.
- No licence information is recorded for this record.
- Because redistribution is not established, this page shows the abstract only. Follow the links below for the full text.
Abstract
That neutrinos carry a nonvanishing rest mass is evidence of physics beyond the Standard Model of elementary particles. Their absolute mass holds relevance in fields from particle physics to cosmology. We report on the search for the effective electron antineutrino mass with the KATRIN experiment. KATRIN performs precision spectroscopy of the tritium β-decay close to the kinematic endpoint. On the basis of the first five measurement campaigns, we derived a best-fit value of [Formula: see text] eV<sup>2</sup>, resulting in an upper limit of <i>m</i><sub>ν</sub> < 0.45 eV at 90% confidence level. Stemming from 36 million electrons collected in 259 measurement days, a substantial reduction of the background level, and improved systematic uncertainties, this result tightens KATRIN's previous bound by a factor of almost two.