Ghost particle on the scales

What is the mass of a neutrino at rest? This is one of the big unanswered questions in physics. Neutrinos play a central role in nature. A team led by Klaus Blaum, Director at the Max Planck Institute for Nuclear Physics in Heidelberg, has now made an important contribution in "weighing" neutrinos as part of the international ECHo collaboration. Using a so-called Penning trap, it has measured the change in mass of a holmium-163 isotope with extreme precision when its nucleus captures an electron and turns into dysprosium-163. From this, it was able to determine the so-called Q value 50 times more accurately than before. Using a more precise Q-value, possible systematic errors in the determination of the neutrino mass can be revealed.

Please read more in the Nature Physics Article and our press release.

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