Experts were already treating the discovery as such a sensation that even the word “deserves a Nobel Prize”: in 2018, scientists from the “MiniBooNE” experiment at the American research laboratory Fermilab near Chicago presented it A bewildering excess of electron neutrinos in their measurements, which does not fit the classical standard model of elementary particles. But new data from the follow-up experiment “MicroBooNE” now appears: None. “The results are either in agreement with or just below the predictions of the neutrino-enhanced beam rate, and no excess of electron neutrinos was observed,” The research group writes in the current issue of “Physical Review Letters”. Goodbye Nobel Prize.
The “MiniBooNE” experiment, begun in 2002, was intended to confirm the result of the LSND neutrino experiment at Los Alamos National Laboratory in the 1990s, in which a very large number of electron neutrinos were measured for the first time. The discovery caused outrage at the time, because there was no clear explanation. So experts speculated that these neutrinos could be “sterile” interacting with matter to a lesser degree than their relatives, the electron, muon and tau neutrinos, who are already shy. Physicists hope and still hope that if this materializes, some of the unanswered questions of the universe might come close, such as the search for dark matter or even the formula of the world. And indeed, the excitement in 2018 was great.
In such measurements, scientists examine what is known as neutrino oscillation – a quantum mechanical phenomenon in which neutrinos are constantly changing into one another. This behavior was first observed in the 1960s, when scientists measured far fewer neutrinos emitted from the Sun than expected. But it took decades and a lot of experimental work to prove conclusively that these “missing” neutrinos did not disappear during their journey back to Earth, but simply morphed into the other two types of neutrinos.