Type of dual superconductivity for the SU(2)SU(2) Yang--Mills theory

We investigate the type of dual superconductivity responsible for quark confinement. For this purpose, we solve the field equations of the $U(1)$ gauge-scalar model to obtain the static vortex solution in the whole range without restricting to the long-distance region. Then we use the resulting magnetic field of the vortex to fit the gauge-invariant chromoelectric field connecting a pair of quark and antiquark which was measured by numerical simulations for $SU(2)$ Yang--Mills theory on a lattice. This result improves the accuracy of the fitted value for the Ginzburg--Landau parameter to reconfirm the type I dual superconductivity for quark confinement which was claimed by preceding works based on a fitting using the Clem ansatz. Moreover, we calculate the Maxwell stress tensor to obtain the distribution of the force around the flux tube. This result suggests that the attractive force acts among chromoelectric flux tubes, in agreement with the type I dual superconductivity.Comment: 15 pages, v4-published versio

New Experimental Limit on the Electric Dipole Moment of the Electron in a Paramagnetic Insulator

We report results of an experimental search for the intrinsic Electric Dipole Moment (EDM) of the electron using a solid-state technique. The experiment employs a paramagnetic, insulating gadolinium gallium garnet (GGG) that has a large magnetic response at low temperatures. The presence of the eEDM would lead to a small but non-zero magnetization as the GGG sample is subject to a strong electric field. We search for the resulting Stark-induced magnetization with a sensitive magnetometer. Recent progress on the suppression of several sources of background allows the experiment to run free of spurious signals at the level of the statistical uncertainties. We report our first limit on the eEDM of $(-5.57 \pm 7.98 \pm 0.12)\times$10$^{-25}$e$\cdot$cm with 5 days of data averaging.Comment: 9 pages, 9 figures, Revtex 4.

A versatile electrostatic trap

A four electrode electrostatic trap geometry is demonstrated that can be used to combine a dipole, quadrupole and hexapole field. A cold packet of 15ND3 molecules is confined in both a purely quadrupolar and hexapolar trapping field and additionally, a dipole field is added to a hexapole field to create either a double-well or a donut-shaped trapping field. The profile of the 15ND3 packet in each of these four trapping potentials is measured, and the dependence of the well-separation and barrier height of the double-well and donut potential on the hexapole and dipole term are discussed.Comment: submitted to pra; 7 pages, 9 figure

The BNL Muon Anomalous Magnetic Moment Measurement

The E821 experiment at Brookhaven National Laboratory is designed to measure the muon magnetic anomaly, a_mu, to an ultimate precision of 0.4 parts per million (ppm). Because theory can predict a_mu to 0.6 ppm, and ongoing efforts aim to reduce this uncertainty, the comparison represents an important and sensitive test of new physics. At the time of this Workshop, the reported experimental result from the 1999 running period achieved a_mu = 11 659 202(14)(6)x 10^-10 (1.3 ppm) and differed from the most precise theory evaluation by 2.6 standard deviations. Considerable additional data has already been obtained in 2000 and 2001 and the analysis of this data is proceeding well. Intense theoretical activity has also taken place ranging from suggestions of the new physics which could account for the deviation to careful re-examination of the standard model contributions themselves. Recently, a re-evaluation of the pion pole contribution to the hadronic light-by-light process exposed a sign error in earlier studies used in the standard theory. With this correction incorporated, experiment and theory disagree by a modest 1.6 standard deviations.Comment: To be published in the Proceedings of the Workshop on Electromagnetic Probes of Fundamental Physics, Erice, 16 - 21 October 2001 (On behalf of the Brookhaven E821 Collaboration) Uses 13 ps/eps figures. 14 pages tota

Effects of Intermittent Emission: Noise Inventory for Scintillating Pulsar B0834+06

We compare signal and noise for observations of the scintillating pulsar B0834+06, using very-long baseline interferometry and a single-dish spectrometer. Comparisons between instruments and with models suggest that amplitude variations of the pulsar strongly affect the amount and distribution of self-noise. We show that noise follows a quadratic polynomial with flux density, in spectral observations. Constant coefficients, indicative of background noise, agree well with expectation; whereas second-order coefficients, indicative of self-noise, are about 3 times values expected for a pulsar with constant on-pulse flux density. We show that variations in flux density during the 10-sec integration account for the discrepancy. In the secondary spectrum, about 97% of spectral power lies within the pulsar's typical scintillation bandwidth and timescale; an extended scintillation arc contains about 3%. For a pulsar with constant on-pulse flux density, noise in the dynamic spectrum will appear as a uniformly-distributed background in the secondary spectrum. We find that this uniform noise background contains 95% of noise in the dynamic spectrum for interferometric observations; but only 35% of noise in the dynamic spectrum for single-dish observations. Receiver and sky dominate noise for our interferometric observations, whereas self-noise dominates for single-dish. We suggest that intermittent emission by the pulsar, on timescales < 300 microseconds, concentrates self-noise near the origin in the secondary spectrum, by correlating noise over the dynamic spectrum. We suggest that intermittency sets fundamental limits on pulsar astrometry or timing. Accounting of noise may provide means for detection of intermittent sources, when effects of propagation are unknown or impractical to invert.Comment: 38 pages, 10 figure

Electron mobility maximum in dense argon gas at low temperature

We report measurements of excess electron mobility in dense Argon gas at the two temperatures $T=152.15$ and 162.30 K, fairly close to the critical one ($T_c =150.7$ K), as a function of the gas density $N$ up to 14 atoms$\cdot$nm$^{-3}$ ($N_{c}=8.08$ atoms$\cdot$nm$^{-3}$). For the first time a maximum of the zero-field density-normalized mobility $\mu_{0}N$ has been observed at the same density where it was detected in liquid Argon under saturated vapor pressure conditions. The existence of the $\mu_{0}N$ maximum in the liquid is commonly attributed to electrons scattering off long-wavelength collective modes of the fluid, while for the low-density gas a density-modified kinetic model is valid. The presence of the $\mu_{0}N$ maximum also in the gas phase raises therefore the question whether the single scattering picture valid in the gas is valid even at liquid densities.Comment: 21 pages, 9 figures, accepted for publication in J. Electrostatic

Measurement of the Permanent Electric Dipole Moment of the 129^{129}Xe Atom

We report on a new measurement of the CP-violating permanent Electric Dipole Moment (EDM) of the neutral $^{129}$Xe atom. Our experimental approach is based on the detection of the free precession of co-located nuclear spin-polarized $^3$He and $^{129}$Xe samples. The EDM measurement sensitivity benefits strongly from long spin coherence times of several hours achieved in diluted gases and homogeneous weak magnetic fields of about 400~nT. A finite EDM is indicated by a change in the precession frequency, as an electric field is periodically reversed with respect to the magnetic guiding field. Our result, $\left(-4.7\pm6.4\right)\cdot 10^{-28}$ ecm, is consistent with zero and is used to place a new upper limit on the $^{129}$Xe EDM: $|d_\text{Xe}|<1.5 \cdot 10^{-27}$ ecm (95% C.L.). We also discuss the implications of this result for various CP-violating observables as they relate to theories of physics beyond the standard model