Neutrino Mass Breakthrough at Karlsruhe Experiment

In a groundbreaking achievement, the Karlsruhe Tritium Neutrino (KATRIN) experiment in Germany has set a new world record by refining the upper limit of the neutrino mass. This milestone, achieved through collaborative efforts of over twenty research institutions from seven countries, marks a significant advancement in particle physics.

Unveiling the Mysteries of Neutrinos

Neutrinos, elusive particles that permeate the universe, play a crucial role in shaping large-scale galactic structures. Their minuscule yet non-zero mass serves as a key indicator of previously unknown physical processes. Precise measurement of neutrino mass is essential for understanding the fundamental laws of nature and determining the overall mass of the universe.

The experiment, utilizing the beta decay of tritium, an unstable hydrogen isotope, employs a spectrometer to measure neutrino mass. The new limit is 0.45 electronvolts, improving upon the 2022 result by 0.35 electronvolts. "The current upper limit keeps KATRIN at the top of the world rankings in the field of direct neutrino mass measurement," stated Kathrin Valerius from the Karlsruhe Institute of Technology (KIT).

Czech Scientists' Contribution

A team from the Institute of Nuclear Physics of the Czech Academy of Sciences significantly contributed to the experiment. Their key contribution was the development of a gaseous source of monoenergetic electrons based on the radioactive decay of a krypton isotope. According to Drahoslav Vénos, this source is the gold standard for energy calibration and allows for crucial corrections in determining neutrino mass.

The quest to determine neutrino mass has captivated physicists since the early 20th century. Early attempts in 1948 set the upper limit at 5000 electronvolts, a value 11,000 times higher than the current result. This new measurement represents a monumental leap in our understanding of these fundamental particles.