An international team of researchers has used a new spectrometer to find and set an upper limit for the mass of a neutrino. In their paper published in the journal Physical Review Letters, the group describes how they came up with the new limit...
[...] The researchers carried out their work as part of the Karlsruhe Tritium Neutrino Experiment (KATRIN) on the campus of the Karlsruhe Institute of Technology in Germany. The core piece of equipment used at the site is a 200-ton electron spectrometer. The researchers used it to study the decay of tritium—a radioactive type of hydrogen. When it decays, it emits a single electron and a neutrino at the same time. By measuring the energy of the released electron using the spectrometer, they were able to calculate an estimate of the mass of the neutrino to a greater precision than was possible before. They found its upper limited to be 1.1 electronvolts, approximately half of the previously determined upper limit. It is also extremely tiny—approximately 500,000 times smaller than an electron.
More information: M. Aker et al. Improved Upper Limit on the Neutrino Mass from a Direct Kinematic Method by KATRIN, Physical Review Letters (2019). DOI: 10.1103/PhysRevLett.123.221802 . On Arxiv: https://arxiv.org/abs/1909.06048
(Score: 1, Insightful) by Anonymous Coward on Wednesday November 27 2019, @10:54AM
Also, the faster than light neutrinos were not a statistical fluke. The statistics correctly told them at least one of the assumptions behind the null hypothesis was wrong... Just like it promised to do.