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.

A precise measurement of the anomalous g value, aµ = (g − 2)/2, for the positive muon has been made at the Brookhaven Alternating Gradient Synchrotron. The result a µ + = 11 659 202(14)(6) × 10 −10 (1.3 ppm) is in good agreement with previous measurements and has an error one third that of the combined previous data. The current theoretical value from the standard model is aµ(SM)= 11 659 159.6(6.7) × 10 −10 (0.57 ppm) and aµ(exp)−aµ(SM) = 43(16) × 10 −10 in which aµ(exp) is the world average experimental value.PACS number: 14.60.Ef 13.40.EmPrecise measurement of the anomalous g value, a µ = (g−2)/2, of the muon provides a sensitive test of the standard model of particle physics and new information on speculative theories beyond it. Compared to the electron, the muon g value is more sensitive to standard model extensions, typically by a factor of (m µ /m e ) 2 . In this Letter we report a measurement of a µ for the positive muon from Brookhaven AGS experiment 821, based on data collected in 1999.The principle of the experiment, previous results, and many experimental details have been given in earlier publications [1,2]. Briefly, highly polarized µ + of 3.09 GeV/c from a secondary beamline are injected through a superconducting inflector [3] into a storage ring 14.2 m in diameter with an effective circular aperture 9 cm in diameter. The superferric storage ring [4] has a homogeneous magnetic field of 1.45 T, which is measured by an NMR system relative to the free proton NMR frequency [5,6]. Electrostatic quadrupoles provide vertical focusing. A pulsed magnetic kicker gives a 10 mrad deflection which places the muons onto stored orbits. The muons start in 50 ns bunches and debunch with a decay time of about 20 µs due to their 0.6% momentum spread. Positrons are detected using 24 lead/scintillating fiber electromagnetic calorimeters [7] read out by waveform digitizers. The waveform digitizer and NMR clocks were phase-locked to the Loran C frequency signal.The muon spin precesses faster than its momentum rotates by an angular frequency ω a in the magnetic field B weighted over the muon distribution in space and time. The quantity a µ iswhere ω a is unaffected by the electrostatic field for muons with γ = 29.3. Parity violation in the decay µ + → e +ν µ ν e causes positrons to be emitted with an angular and energy asymmetry. Because of the Lorentz boost, the positron emission angle with respect to the muon spin direction in the muon rest frame is strongly coupled to its energy in the laboratory frame. The number of decay positrons with energy greater than E is described byin which the time dilated lifetime γτ ≈ 64.4 µs. Some 140 g − 2 periods of 4.37 µs were observed. Most experimental aspects of the data taking in 1999 were the same as in 1998 [1]. However, some improvements were made. Care was taken in tuning the AGS ejection system to minimize background from any extraneous proton beam extracted during the muon storage time. Scintillating fiber detectors which could be moved in and out of the storage region were u...

Hybridization of HI-labeled ribosomal RNA to human chromosomes on slides resulted in specific labeling of the satellite regions of chromosomes 13, 14, 15, 21, and 22, with an over-all efficiency of about 5%. Differences between D and G chromosomes, and between associated and unassociated satellites, were not significant. Labeling of all other parts of the preparations was nonspecific, and increased in the order: extrachromosomal regions < chromosome arms < centric regions.Three lines of evidence bear on the localization of rDNA in the human genome. First, the satellited chromosomes tend to be associated with the nucleolus (1, 2). Second, when isolated chromosomes are fractionated, enrichment for small chromosomes enriches for rDNA (3). Third, with DNA from cell lines having different ratios of acrocentric to total chromosomes, rRNA-DNA hybridization increases with the relative number of acrocentrics (4). Such results are consistent with the presence of rDNA in some combination of chromosomes 13, 14, 15, 21, and 22, but do not resolve whether all of these chromosomes, are uniquely involved.We have used the technique of in situ hybridization (5)

The proportions of chromosomal genotypes associated with the Turner syndrome genotype (excluding those with a Y chromosome) in embryonic and fetal deaths, in fetuses diagnosed prenatally, and in living individuals were reviewed. The ratio of apparent non-mosaic 45,X to 45,X/46,XX mosaics was notably higher in a New York City series of embryonic and fetal deaths, 13.5 to 1, than in living individuals reported to the New York State Chromosome Registry, 3.6 to 1. The ratios of 45,X cases to those with 46,Xi(Xq) was 5.7 to 1 in living individuals, but was 112 to 0 in embryonic and fetal deaths, an even greater disparity, indicating the marked fetoprotective effect of more than one dose of some locus or loci on the long arm of the X chromosome. The results of review of data pertinent to the livebirth prevalence of the (apparent non-mosaic) 45,X genotype suggest a rate of about 5.7 per 100,000 livebirths (11.8 per 100,000 females) with 95% confidence limits of 2.6 per 100,000 to 10.8 per 100,000. The rate in fetuses diagnosed prenatally is 8/27,202, about 30 per 100,000. As a large proportion of these, perhaps 75%, would undergo spontaneous fetal death if not terminated electively, these figures are consistent with the direct estimate of livebirth rates. The rate of all those with X chromosome abnormalities (with a Y chromosome) associated with signs or symptoms that eventually lead to referral for cytogenetic study was estimated at a minimum of 10.7 per 100,000 livebirths, (22.2 per 100,000 females).

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.