Speaker
Dr
Glen Marshall
(TRIUMF)
Description
The anomalous magnetic moment of the muon, a_mu = (g_mu - 2)/2,
has been measured to 0.54 ppm at BNL (E821), and when compared to
the Standard Model (SM) calculation of similar precision, a
discrepancy of about 3 sigma remains unexplained. A similar
method will be used at FNAL (E989) with the goal of achieving a
factor of four increase in experimental precision.
An independent method is being exploited for the J-PARC muon
g-2/EDM experiment (E34). It uses a smaller high-precision
storage ring for 300 MeV/c muons with no requirement for electric
field focusing. Storage is achieved due to the extremely small
momentum spread of the beam, maintained through acceleration of
room-temperature thermal muons. The method offers many
advantages, and relies on a thermal muon source derived from
laser ionization of muonium atoms emitted from silica aerogel
structures. The yields and properties of the muonium in vacuum
are being studied at TRIUMF as well as at RIKEN/RAL and J-PARC.
The status of the muonium experiments will be presented, showing
the substantial increase in thermal muonium yield from
laser-ablated aerogel materials and the current understanding
based on model-independent analysis as well as comparison with
simulations based on muonium diffusion.
Primary author
Dr
Glen Marshall
(TRIUMF)
