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It is shown that the Lorentz transformation cannot in general be formally applied to potentials and fields of particles locked in a certain region. In particular, this property relates to nucleons in nuclei and to particles and nuclei in storage rings. Even if they move with high velocities, their electric fields are defined by the Coulomb law. The result obtained is rather important for the planned deuteron electric-dipole-moment experiment in storage rings. [ABSTRACT FROM AUTHOR]

The ion-optical properties of the single gap extraction system of the mVINIS ion source are investigated. The pepper-pot method was used to measure the effective emittances of the ion beams extracted from the plasma. The emittances have been analyzed as functions of the extraction electrode position for various charge states of the ion species. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

A diagnostic device is described for estimating the beam emittance per pulse (for pulse durations from 1 µs up to a continuous beam) for ion beams of circular cross section with currents from a few milliamperes to hundreds of milliamperes and energies of 10 keV and higher. [ABSTRACT FROM AUTHOR]

A correction to the article "The effects of nonlinear phase for the generation and propagation of finite energy Airy beams" that was published in the 2013 issue is presented.

The article discusses the approval by the U.S. Department of Energy (DOE) of a facility to generate rare isotopes in the fields of nuclear physics, astrophysics, and medical diagnostics. Michigan State University and Argonne National Laboratory in Illinois, competed to host the Facility of Rare Isotope Beams (FRIB). An brief overview of the facility's linear accelerator, which is the centerpiece of the FRIB, is presented.

A probabilistic data analysis method was applied to analyze the spatially resolved beam emission intensities from the lithium beam diagnostic at ASDEX Upgrade. The method allows us to recover density profiles from the Li I emission profile with a spatial resolution of 5 mm and a temporal resolution of 50 µs. It is based on a probabilistic description of the measured data including absolutely calibrated measurement errors, a forward model for the simulation of the data given a density profile, and prior information about weak constraints on monotonicity. The density profile is parametrized by cubic spline polynomials. The method replaces the conventional approach applying an iterative (shooting) method to invert the density profile. The new probabilistic method allows us to analyze low-density profiles since there is no need to fulfil an inner boundary condition or to pre-smooth measured data because no direct inversion occurs. Consistent profile uncertainty measures are provided for different purposes. Profiles in the edge region can be fully explored for any plasma regime and the profile pedestal is accessible up to 0.8 × 1020 m[?]3. The advanced technique is demonstrated with low, medium and high density profiles at ASDEX Upgrade. The benefit of the achieved temporal resolution is shown with ELM resolved measurements. The dependence of the density profiles on electron temperature or impurity content is shown to be negligible. [ABSTRACT FROM AUTHOR]

An eight-channel beam-emission-spectroscopy (BES)1 system has been installed on the Alcator C-Mod tokamak, intended for use with a diagnostic neutral hydrogen beam (DNB). Capable of localized measurements from the plasma edge to the plasma core, the BES diagnostic collects light from the first Balmer transition (H[sub α]) resultant from beam/plasma collisions. The H[sub α] line splits into several components whose central wavelengths depend on the viewing geometry, the magnetic field, and the beam energy. This is due to the Doppler shifts from viewing the beam off perpendicular, the different velocities of the three mass components of the beam (H, H[sub 2], H[sub 3]), and the large motional Stark effect. Optimal signal-to-noise requires collecting these components while attenuating all other emission: primarily bremsstrahlung and D[sub α] radiation (from plasma D[sup 0]/e[sup -] collisions). Tunable bandpass filters are thus required. A BES simulation code has been developed that calculates the brightnesses (bremsstrahlung, D[sub α], H[sub α]) versus wavelength using plasma profile data from the C-Mod MDSplus database,2 a computation of the beam penetration, the viewing and DNB geometries, and bandpass filter characteristics. The model was first used to estimate signal levels and choose the optimal BES bandpass filters; its ultimate purpose is to determine the shot-to-shot tuning requirements of the filters for different discharge conditions. Comparisons of measured and predicted background bremsstrahlung and D[sub α] brightnesses are presented, as are first measurements and calculations of the beam emission. The code is written in the IDL programming language3 utilizing the “widget” graphical user interface. Designed for geometrical and spectral flexibility, it can be modified to simulate other beam diagnostics such as motional-Stark-effect plasma current measurements and charge-exchange recombination spectrosco... [ABSTRACT FROM AUTHOR]

Discusses an abstract about sectional and projectional emittance measurements. Ion sources; Determining parameters for beam quality; Observation of clear aberrative distortions of the emittance during projection of the four-dimensional space onto a two-dimensional plane.