Preparation and first result of BNL experiment E821: 'A new precision measurement of the Muon (g-2) value'
Abstract
The new muon (g-2) experiment had prepared at the Brookhaven National Laboratory (BNL) to push experimental uncertainty in au = 1/2(gu-2) down by a factor of 20. That would allow to measure the weak interaction contribution to au at the level of four standard deviations and probe the physics beyond the Standard Model. The first (``engineering'') run with pion injection was successfully made in 1997. The result obtained from this run is: au+=116592 500(1520)×10∧ -11(13.0ppm), which is comparable in precision and in agreement with previous most precise measurements at CERN: au+=116591 000(1100)×10∧ -11(9.4ppm),
au+=116592 300(380)×10∧ -11(7.2ppm). Both CERN and BNL results are in agreement with current theoretical value: Au=116591628( 77)×10∧-11( 0.66ppm). </display- math> Further improvements in accuracy of au (experiment ) is expected from 1908 and 1999 runs with direct muon injection, which would provide higher number of stored muons, and less systematic error. Further improvements in accuracy of au (theory) is also expected in one or two years, mostly from more precise measurement of hadron vacuum polarization contribution at CMD-2 experiment, Novosibirsk, Russia.- Publication:
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Ph.D. Thesis
- Pub Date:
- November 1999
- Bibcode:
- 1999PhDT........90R
- Keywords:
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- Physics: Elementary Particles and High Energy