Measurement of the Negative Muon Anomalous Magnetic Moment to 0.7 ppm

The anomalous magnetic moment of the negative muon has been measured to a precision of 0.7 parts per million (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 of the negative muon. The result a_mu= 11 659 214(8)(3) \times 10^{-10} (0.7 ppm), where the first uncertainty is statistical and the second is sytematic, is consistend with previous measurements of the anomaly for the positive and negative muon. The average for the muon anomaly a_{mu}(exp) = 11 659 208(6) \times 10^{-10} (0.5ppm).Comment: 4 pages, 4 figures, submitted to Physical Review Letters, revised to reflect referee comments. Text further revised to reflect additional referee comments and a corrected Fig. 3 replaces the older versio

Quantum Gravity in Everyday Life: General Relativity as an Effective Field Theory

This article is meant as a summary and introduction to the ideas of effective field theory as applied to gravitational systems. Contents: 1. Introduction 2. Effective Field Theories 3. Low-Energy Quantum Gravity 4. Explicit Quantum Calculations 5. ConclusionsComment: 56 pages, 2 figures, JHEP style, Invited review to appear in Living Reviews of Relativit

Radial magnetic field measurements with a Hall probe device in the muon (g-2) storage ring magnet at BNL

A Hall probe device has been built to measure the radial component of the magnetic field in the muon (g-2) storage ring at Brookhaven National Laboratory. The ultraprecise (g-2) magnet provides a dominantly vertical magnetic field of about 1.45 T. In order to limit the vertical shift of the muon orbit, the average radial field component should be no more than 5 x 10(-5) of, the vertical field. Our measurements with the Hall probe device achieved an accuracy of 1 x 10(-5). which is one of the most precise measurements with Hall probes. This provides adequate accuracy for shimming and control of the radial field. (C) 2001 Elsevier Science B.V. All rights reserved

The Brookhaven muon storage ring magnet

The muon g-2 experiment at Brookhaven National Laboratory has the goal of determining the muon anomalous g-value a(mu) ( = (g - 2)/2) to the very high precision of 0.35 parts per million and thus requires a storage ring magnet with great stability and homogeniety. A superferric storage ring with a radius of 7.11 m and a magnetic field of 1.45 T has been constructed in which the field quality is largely determined by the iron, and the excitation is provided by superconducting coils operating at a current of 5200 A. The storage ring has been constructed with maximum attention to azimuthal symmetry and to tight mechanical tolerances and with many features to allow obtaining a homogenous magnetic field. The fabrication of the storage ring, its cryogenics and quench protection systems, and its initial testing and operation are described. (C) 2001 Elsevier Science B.V. All rights reserved