Thursday, October 12, 2023, 16:00
WHGA Auditorium
René Reimann, Mainz University
Abstract:
The Standard Model of Particle Physics is the best tested theory today
describing all known elementary particles and interactions of the
electro-magnetic, strong and weak forces. However, it is known that
there is physics beyond the Standard Model, most prominent it lacks to
explain gravity. Extremely sensitive tests of the completeness of the
Standard Model compare highest precision measurements with theoretical
predictions of equivalent precision. The magnetic moment anomaly of the
muon is one of the most precisely measured and predicted quantities. A
60-year long history of improved measurements and improved theoretical
understanding lead the way from the first prediction of the muons
magnetic moment (g=2) to the previously best measured value of the
magnetic anomaly with a precision of 400 ppb. Recently the Fermilab
Muon g-2 experiment reported its most recent results from measurement
campaigns 2 and 3 and thus doubled the precision on the measured
magnetic anomaly of the muon, now at 200 ppb. The increase in precision
is both due to increased statistics and reduced systematics and puts the
Muon g-2 experiment well on its way towards its design precision of 140
ppb with final statistics. In this colloquium we review the measurement
principle of the Muon g-2, point out experimental improvements in the
recent measurement and put the measurement in the context of the current
theoretical effort.