NOVOSIBIRSK, April 18Specialists of the Institute of Nuclear Physics. G.I. Budker of the Siberian Branch of the Russian Academy of Sciences at the VEPP-2000 collider received a world scientific result that complicates the path of searching for «new physics» that can change mankind's ideas about the structure of the Universe, Ivan Logashenko, Deputy Director for Research at the INP SB RAS, told reporters.
An unexpected result for the world community and extremely significant for particle physics was obtained on the CMD-3 cryogenic magnetic detector of the VEPP-2000 electron-positron collider at the Institute of Nuclear Physics. He makes a significant contribution to the international experiment Muon g-2.
«After our measurement, it is clear that the large difference that was observed earlier between the Standard Model and the measured value of the muon's anomalous magnetic moment is significantly reduced. This result is very interesting, because in a sense it solves the 20-year-old puzzle,» Logashenko said.
He noted that the INP SB RAS does not understand why the results of the obtained measurements differ significantly from the previous experiments on measuring the anomalous magnetic moment of the muon, but they are confident in the correctness of the result. The best recognition of the work, he said, would be its confirmation in other world centers of particle physics.
«Does our result close the possibility that there is a 'new physics'? Of course not, because this is a matter of accuracy. The heavier the particles that we have not yet discovered, the less they contribute to the muon's anomalous magnetic moment, so our resolution — up to what energies we will see the contribution of hypothetical particles depends on the accuracy of measurements. With the accuracy with which we measured — yes, it does. That is, we can say that there cannot be particles lighter than such and such a mass, but particles of large mass, which we cannot see with the accuracy of our measurements,» the scientist said.
Over the past 20 years, physicists have discovered a lot of evidence of the existence of «new physics» outside the Standard Model of behavior and interaction between a number of elementary particles. One of the possible explanations for this may be the existence of previously undiscovered particles or forces. One of the most famous anomalies of this kind was the unusual nature of the «magnetization» of the muon — an elementary particle that has the same properties as an electron, but 207 times more mass.
The large-scale experiment Muon g-2 is dedicated to measuring the anomalous magnetic moment of the muon. One of the main tasks of the experiment, which is being carried out by the specialists of the National Accelerator Laboratory named after V.I. Enrico Fermi (Fermilab, USA) is the search for «new physics» — unknown particles and their interactions, not described by the Standard Model. Research closely related to this experiment has been carried out at the INP SB RAS since 1989.