We present the final report from a series of precision measurements of the muon anomalous magnetic moment, a µ = (g − 2)/2. The details of the experimental method, apparatus, data taking, and analysis are summarized. Data obtained at Brookhaven National Laboratory, using nearly equal samples of positive and negative muons, were used to deduce a µ (Expt) = 11 659 208.0(5.4)(3.3) × 10 −10 , where the statistical and systematic uncertainties are given, respectively. The combined uncertainty of 0.54 ppm represents a 14-fold improvement compared to previous measurements at CERN. The standard model value for a µ includes contributions from virtual QED, weak, and hadronic processes. While the QED processes account for most of the anomaly, the largest theoretical uncertainty, ≈ 0.55 ppm, is associated with first-order hadronic vacuum polarization. Present standard model evaluations, based on e + e − hadronic cross sections, lie 2.2 -2.7 standard deviations below the experimental result.

The anomalous magnetic moment of the negative muon has been measured to a precision of 0.7 ppm (ppm) at the Brookhaven Alternating Gradient Synchrotron. This result is based on data collected in 2001, and is over an order of magnitude more precise than the previous measurement for the negative muon. The result a(mu(-))=11 659 214(8)(3) x 10(-10) (0.7 ppm), where the first uncertainty is statistical and the second is systematic, is consistent with previous measurements of the anomaly for the positive and the negative muon. The average of the measurements of the muon anomaly is a(mu)(exp)=11 659 208(6) x 10(-10) (0.5 ppm).

Three independent searches for an electric dipole moment (EDM) of the positive and negative muons have been performed, using spin precession data from the muon g À 2 storage ring at Brookhaven National Laboratory. Details on the experimental apparatus and the three analyses are presented. Since the individual results on the positive and negative muons, as well as the combined result, d ¼ ð0:0 AE 0:9Þ Â 10 À19 e cm, are all consistent with zero, we set a new muon EDM limit, jd j < 1:8 Â 10 À19 e cm (95% C.L.). This represents a factor of 5 improvement over the previous best limit on the muon EDM.

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A higher precision measurement of the anomalous g value, aµ = (g − 2)/2, for the positive muon has been made at the Brookhaven Alternating Gradient Synchrotron, based on data collected in the year 2000. The result a µ + = 11 659 204(7)(5) × 10 −10 (0.7 ppm) is in good agreement with previous measurements and has an error about one half that of the combined previous data. The present world average experimental value is aµ(exp) = 11 659 203(8) × 10 −10 (0.7 ppm). The study of magnetic moments has played an important role in our understanding of sub-atomic physics. Precision measurements of the electron anomalous magnetic moment, together with those of the hyperfine structure of hydrogen and the Lamb shift, stimulated the development of modern quantum electrodynamics and have since provided stringent tests of this theory. In this Letter we report a new measurement of the anomalous magnetic moment of the positive muon, a µ = (g − 2)/2, with a relative precision of 0.7 parts per million (ppm), nearly two times better than our previous work [1,2,3]. This measurement comes from data collected in the year 2000. At this level, a µ is sensitive to QED, weak, and hadronic virtual loops and provides an important constraint on extensions to the standard model.The principle of the experiment and previous results have been given in earlier publications [1,2,3]. Also, detailed descriptions of the (g − 2) superconducting inflector magnet, storage ring magnet, fast kicker, NMR system, and calorimeters have been published [4].The quantity a µ is determined fromThe magnetic field B weighted over the muon beam distribution is measured by proton NMR. The difference frequency ω a between the muon spin precession and orbital angular frequencies is determined by counting the number N (t) of decay positrons with energies larger than an energy threshold,The normalization N 0 , asymmetry A, and phase φ a vary with the chosen threshold. The time dilated lifetime is γτ ≈ 64.4 µs. For muons with γ = 29.3, the angular difference frequency ω a is not affected by electrostatic focusing fields in the ring. New aspects of the 2000 data taking period include: the operation of the AGS with 12 beam bunches, contributing to a 4-fold increase in data collected as compared to 1999; a new superconducting inflector magnet, which improved the field homogeneity in the muon storage region; the installation and operation of a sweeper magnet in the beamline, which reduced AGS background; and additional muon loss detectors, which enable an improved determination of the time dependence of muon losses. Most other experimental aspects of the data taking in 2000 were the same as in 1998 and 1999.The magnetic field value was obtained from NMR measurements of the free proton resonance frequency. A trolley with 17 NMR probes was used to measure the field

We conducted a search for technosignatures in 2018 and 2019 April with the L-band receiver (1.15–1.73 GHz) of the 100 m diameter Green Bank Telescope. These observations focused on regions surrounding 31 Sun-like stars near the plane of the Galaxy. We present the results of our search for narrowband signals in this data set, as well as improvements to our data processing pipeline. Specifically, we applied an improved candidate signal detection procedure that relies on the topographic prominence of the signal power, which nearly doubles the signal detection count of some previously analyzed data sets. We also improved the direction-of-origin filters that remove most radio frequency interference (RFI) to ensure that they uniquely link signals observed in separate scans. We performed a preliminary signal injection and recovery analysis to test the performance of our pipeline. We found that our pipeline recovers 93% of the injected signals over the usable frequency range of the receiver and 98% if we exclude regions with dense RFI. In this analysis, 99.73% of the recovered signals were correctly classified as technosignature candidates. Our improved data processing pipeline classified over 99.84% of the ∼26 million signals detected in our data as RFI. Of the remaining candidates, 4539 were detected outside of known RFI frequency regions. The remaining candidates were visually inspected and verified to be of anthropogenic nature. Our search compares favorably to other recent searches in terms of end-to-end sensitivity, frequency drift rate coverage, and signal detection count per unit bandwidth per unit integration time.

The spin precession frequency of muons stored in the (g − 2) storage ring has been analyzed for evidence of Lorentz and CPT violation. Two Lorentz and CPT violation signatures were searched for: a nonzero ∆ωa (=ω PACS numbers: 11.30.Cp, 11.30.Er, 13.40.Em, 12.20.Fv, 14.60.Ef The minimal standard model of particle physics is Lorentz and CPT invariant. Since the standard model is expected to be the low-energy limit of a more fundamental theory such as string theory that incorporates gravity, Lorentz and CPT invariance might be broken spontaneously in the underlying theory [1]. At low energies, the Lorentz and CPT violation signals are expected to be small but perhaps observable in precision experiments.To describe the effects of spontaneous breaking of Lorentz and CPT invariance, Colladay and Kostelecký [2] proposed a general standard model extension that can be viewed as the low-energy limit of a Lorentz covariant theory. Lorentz and CPT violating terms are introduced into the Lagrangian as a way of modeling the effect of spontaneous symmetry breaking in the underlying fundamental theory. Other conventional properties of quantum field theory such as gauge invariance, renormalizability and energy conservation are maintained, and the effective theory can be quantized by the conventional approach. In a subsequent paper, Bluhm, Kostelecký and Lane discussed specific precision experiments with muons that could be sensitive to the CPT and Lorentz violating interactions [3].In this letter we present our analysis for CPT and Lorentz violating interactions in the anomalous spin precession frequency, ω a , of the muon moving in a magnetic field. In experiment E821 [4] at the Brookhaven National Laboratory Alternating Gradient Synchrotron, muons are stored in a magnetic storage ring that uses electrostatic quadupoles for vertical focusing. The storage ring has a highly uniform magnetic field with a central value of B 0 = 1.45 T, and a central radius of ρ = 7.112 m. Polarized muons are injected into the storage ring, and the positrons (electrons) from the parityviolating decay µ +(−) → e +(−)ν µ (ν µ ) ν e (ν e ) carry average information on the muon spin direction at the time of the decay. Twenty-four electromagnetic calorimeters

BackgroundAlthough considered a public health issue in Senegal, the actual incidence and mortality from snakebite are not known. In the present study, an epidemiological survey was carried out in Kédougou region, southeastern Senegal, where envenomations, particularly by Echisocellatus, are frequent and severe.MethodsThree sources of data were used: records from health centers and reports by health professionals; traditional healers; and household surveys.ResultsThe annual incidence and mortality provided by health centers were 24.4 envenomations and 0.24 deaths per 100,000 population, respectively. The annual incidence recorded by traditional healers was 250 bites per 100,000 inhabitants, but the number of deaths was unknown. Finally, the household surveys reported an annual incidence of 92.8 bites per 100,000 inhabitants and an annual mortality rate of 2.2 deaths per 100,000 inhabitants. The differences in incidence and mortality between the different methods were explained by significant bias, resulting in particular from the complex patient’s healthcare-seeking behavior. The incidence provided by health records should be used to specify the immediate quantitative requirements of antivenoms and places where they should be available first.ConclusionMandatory reporting of cases would improve the management of envenomation by simplifying epidemiological surveys. Patients’ preference for traditional medicine should prompt health authorities to urge traditional healers to refer patients to health centers according to defined clinical criteria (mainly edema and bleeding or neurotoxic symptoms). Finally, household surveys were likely to reflect the actual epidemiological situation. Poison Control Center of Senegal should continue its work to sensitize stakeholders and train health staff.