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Evaluates the Isotope Separator Accelerator (ISAC) surface ionization source. Correction of beam aberrations through multiple electrostatic optic elements; Deduction of the root-mean-square-energy spread from emittance measurements; Demonstration of the ISAC facility feasibility for beam energies.

Examines the negative hydrogen/deuterium (H/D) multicusp source in Vancouver, British Columbia. Effect of the gas flow and neutralization on the operation of the source; Differences in the normalized emittance between negative D and H beams; Dependence of the negative D beam current on the pumping speed and arc power.

Studies emission lines in the VUV range in electron cyclotron resonance ion sources, CAPRICE and QUADRUMAFIOS. Observation of emission lines from nearly all ionization states; Comparison of ion densities between CAPRICE and QUADRUMAFIOS.

Reports on the detection and formation of halos developed by an intense proton beam in a long magnetic quadrupole FODO channel. Emittance measurement systems; Ratio of ion species; Percent observed increase emittance for a variation of the pressure by a factor of 2; Energy intensity of proton beams.

Measures the emittance of an ion beam generated on multicusp ion sources. Numerical calculation of the extraction system; Chance of distortion emittance due to the coupling of the radio frequency voltage to the direct current extraction voltage; Beam emittance with and without magnetic filters.

Discusses results of a study of the Los Alamos National Laboratory version of a toroidal-filter, volume negative hydrogen ion source. Set-up of the experimental apparatus; Parametric dependence of the negative hydrogen beam current; Dependence of beam emittance on extraction voltage.

Installs a fast neutral lithium beam on the Texas Experimental Tokamak Upgrade (TEXT-U) project for beam emission spectroscopy studies of the edge plasma electron-density profile. Upgrade of the diagnostic from ten to twenty spatial channels; Spatial and temporal resolution.

Designs a compact and portable eight-channel filter spectrometer for beam emission spectroscopy measurements of long-wavelength density fluctuations on Texas Experimental Tokamak Upgrade (TEXT-U) and Phaedrus-T tokamak projects. Use of radially elongated image volumes; Resolution of dominant fluctuations; Vertical injection geometry of the TEXT-U neutral beam.

Designs a two-dimensional analog to the beam emission spectroscopy (BES) diagnostic to acquire the vorticity and plasma flow-field information. Resolution of spatial and temporal intermittency of plasma turbulent structures; Beam emission imaging diagnostic measures.

The design of a simple all-optical spatial scanner, based on a propagating self-focused channel incident at an oblique angle to a nonlinear dielectric interface, is illustrated using the beam propagation method. The channel asymptotics are shown to be insensitive to the shape of the incident beam profile with the latter satisfying a simple area criterion. [ABSTRACT FROM AUTHOR]

A combined unit, which has the ability to measure the current and emittance of the high intensity direct current (DC) ion beam, is developed at Peking University (PKU). It is a multi-slit single-wire (MSSW)-type beam emittance meter combined with a water-cooled Faraday Cup, named high intensity beam emittance measurement unit-6 (HIBEMU-6). It takes about 15 seconds to complete one measurement of the beam current and its emittance. The emittance of a 50-mA@50-kV DC proton beam is measured. [ABSTRACT FROM AUTHOR]

Low emittance (sub-100 nm rad) measurement of electron beams in plasma accelerators has been a challenging issue for a while. Among various measurement schemes, measurements based on single-shot quad-scan using permanent magnetic quadrupoles (PMQs) has been recently reported with emittance as low as ∼200 nm Weingartner (2012 Phys. Rev. Spec. Top. Accel. Beams15 111302). However, the accuracy and reliability of this method have not been systematically analyzed. Such analysis is critical for evaluating the potential of sub-100 nm rad emittance measurement using any scheme. In this paper, we analyze the effects of various nonideal physical factors on the accuracy and reliability using the PMQ method. These factors include aberration induced by a high order field, PMQ misalignment and angular fluctuation of incoming beams. Our conclusions are as follows: (i) the aberrations caused by high order fields of PMQs are relatively weak for low emittance measurement as long as the PMQs are properly constructed. A series of PMQs were manufactured and measured at Tsinghua University, and using numerical simulations their high order field effects were found to be negligible . (ii) The largest measurement error of emittance is caused by the angular misalignment between PMQs. For low emittance measurement of ∼100 MeV beams, an angular alignment accuracy of 0.1° is necessary. This requirement can be eased for beams with higher energies. (iii) The transverse position misalignment of PMQs and angular fluctuation of incoming beams only cause a translational and rotational shift of measured signals, respectively, therefore, there is no effect on the measured value of emittance. (iv) The spatial resolution and efficiency of the detection system need to be properly designed to guarantee the accuracy of sub-100 nm rad emittance measurement. [ABSTRACT FROM AUTHOR]

A correction to the article "Simulation studies of plasma lens experiments at Daresbury Laboratory" that was published in the October 3, 2016 issue is presented.

A statistical method for the estimation of the spatial correlation lengths of Gaussian-shaped fluctuating signals with two measurement points is examined to quantitatively evaluate its reliability (variance) and accuracy (bias error). The standard deviation of the correlation value is analytically derived for randomly distributed Gaussian shaped fluctuations satisfying stationarity and homogeneity, allowing us to evaluate, as a function of fluctuation-to-noise ratios, the sizes of averaging time windows and the ratios of the distance between the two measurement points to the true correlation length, and the goodness of the two-point measurement for estimating the spatial correlation length. Analytic results are confirmed with numerically generated synthetic data and real experimental data obtained with the KSTAR beam emission spectroscopy diagnostic. Our results can be applied to Gaussian-shaped fluctuating signals where a correlation length must be measured with only two measurement points. [ABSTRACT FROM AUTHOR]

Abstract: The luminosity measurement of the new VEPP-2000 collider based on the Round Colliding Beam concept using SND detector calorimeter is described. [Copyright &y& Elsevier]

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.

Abstract: The azimuthal anisotropy coefficients , characterizing collective flow in Au + Au collisions, are presented for identified particle species as a function of transverse momentum , centrality (cent) and beam collision energy . The values for each particle species, show little, if any, change over the measured beam energy range, and vs. scales to a single curve (constituent quark number scaling) for each n, over a broad range of transverse kinetic energies . A comparison of for individual particle species obtained in Au + Au collisions at (RHIC) and Pb + Pb collisions at (LHC), indicate stronger collective flow at the LHC. These flow measurements and their scaling patterns, can provide important additional constraints for extraction of the specific viscosity . [Copyright &y& Elsevier]

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.