65 research outputs found
Influence of absorbed energy distribution along beam radius on ignition threshold of condensed explosives
The criterion of the condensed explosive ignition by the electron beam, which takes into account Gaussian distribution of electron density along the beam radius, has been obtained. It has been shown that radial heat removal of the absorbed energy leads to the increase in critical ignition energy if the effective track length of electrons in a solid is commensurate with the beam radius. The critical energy of PETN initiation by the electron beam has been calculated
Influence of absorbed energy distribution along beam radius on ignition threshold of condensed explosives
The criterion of the condensed explosive ignition by the electron beam, which takes into account Gaussian distribution of electron density along the beam radius, has been obtained. It has been shown that radial heat removal of the absorbed energy leads to the increase in critical ignition energy if the effective track length of electrons in a solid is commensurate with the beam radius. The critical energy of PETN initiation by the electron beam has been calculated
Muon (g-2) Technical Design Report
The Muon (g-2) Experiment, E989 at Fermilab, will measure the muon anomalous magnetic moment a factor-of-four more precisely than was done in E821 at the Brookhaven National Laboratory AGS. The E821 result appears to be greater than the Standard-Model prediction by more than three standard deviations. When combined with expected improvement in the Standard-Model hadronic contributions, E989 should be able to determine definitively whether or not the E821 result is evidence for physics beyond the Standard Model. After a review of the physics motivation and the basic technique, which will use the muon storage ring built at BNL and now relocated to Fermilab, the design of the new
experiment is presented. This document was created in partial fulfillment of the requirements necessary to obtain DOE CD-2/3 approval
Measurement of the Positive Muon Anomalous Magnetic Moment to 0.20 ppm
We present a new measurement of the positive muon magnetic anomaly, a_{μ}≡(g_{μ}-2)/2, from the Fermilab Muon g-2 Experiment using data collected in 2019 and 2020. We have analyzed more than 4 times the number of positrons from muon decay than in our previous result from 2018 data. The systematic error is reduced by more than a factor of 2 due to better running conditions, a more stable beam, and improved knowledge of the magnetic field weighted by the muon distribution, ω[over ˜]_{p}^{'}, and of the anomalous precession frequency corrected for beam dynamics effects, ω_{a}. From the ratio ω_{a}/ω[over ˜]_{p}^{'}, together with precisely determined external parameters, we determine a_{μ}=116 592 057(25)×10^{-11} (0.21 ppm). Combining this result with our previous result from the 2018 data, we obtain a_{μ}(FNAL)=116 592 055(24)×10^{-11} (0.20 ppm). The new experimental world average is a_{μ}(exp)=116 592 059(22)×10^{-11} (0.19 ppm), which represents a factor of 2 improvement in precision
Measurement of the anomalous precession frequency of the muon in the Fermilab Muon g-2 Experiment
The Muon g-2 Experiment at Fermi National Accelerator Laboratory (FNAL) has
measured the muon anomalous precession frequency to an uncertainty
of 434 parts per billion (ppb), statistical, and 56 ppb, systematic, with data
collected in four storage ring configurations during its first physics run in
2018. When combined with a precision measurement of the magnetic field of the
experiment's muon storage ring, the precession frequency measurement determines
a muon magnetic anomaly of (0.46 ppm). This article describes the multiple techniques employed
in the reconstruction, analysis and fitting of the data to measure the
precession frequency. It also presents the averaging of the results from the
eleven separate determinations of \omega_a, and the systematic uncertainties on
the result.Comment: 29 pages, 19 figures. Published in Physical Review
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