(1) Presentation(s)
Mer. 15/05/2024 09:45 Bâtiment 20, Amphi LELLOUCH Laurent (Centre de Physique Théorique, CNRS, Aix Marseille Univ, IPhU) The mysterious magnetism of the muon (Théorie des Interactions Fondamentales) Nearly twenty years ago in an experiment at Brookhaven National Laboratory, physicists measured the muon's anomalous magnetic moment, a_mu, with a remarkable precision of 0.54 parts per million. Since that time, the reference Standard Model prediction for a_mu has exhibited a discrepancy with experiment of over 3 standard deviations, raising the tantalizing possibility of elementary particles or fundamental forces as yet undiscovered. On April 7, 2021 the physicists of an ongoing experiment at Fermilab presented first results of a new measurement of a_mu, brilliantly confirming Brookhaven's measurement and bringing the discrepancy with the reference prediction to a near discovery level of 4.2 sigma. This discrepancy was further enhanced to 5.1 sigma this past with the publication of Fermilab’s new result that reduces the measurement uncertainty by a factor of 2. According to usual particle physics standards, such a discrepancy would mean that new fundamental physics has been uncovered. Pour plus d'informations, merci de contacter Finco A. |