Aplanatic waxicons

Waxicon mirror components offer many advantages in designing optical systems for transporting high power laser beams. The widespread use of waxicons has been limited because of their high sensitivity to tilt errors. This paper gives the equations of the surfaces of a waxicon that is rigorously corrected for both spherical aberration and coma. Computer ray tracing has confirmed its low sensitivity to tilt errors: if the aplantic waxicon as a whole is tilted by a small angle delta, the RMS wavefront error in the output beam will be proportional to delta/sup 2/

Scheme to funnel ion beams with a radio-frequency quadrupole

We describe a proposed method to funnel ion beams using a new form of the radio-frequency quadrupole (RFQ) structure. This RFQ accepts two bunched ion beams and combines them into a single final beam with interlaced microstructure pulses. It also provides uninterrupted periodic transverse focusing to facilitate the funneling of beams with high current and low emittance

Proposed use of the radio-frequency quadrupole structure to funnel high-current ion beams

In this paper, we describe a new approach to funneling beams that are initially accelerated in two radio-frequency quadrupole (RFQ) accelerators. Instead of discrete optical elements, we propose to funnel within an RFQ structure, so that during the funneling process the beam is always confined by periodic transverse focusing. Beams with high space charge experience irreversible emittance growth when they emerge from a periodic focusing system. To alleviate this problem, in the proposed funneling system it should be possible to maintain the same focusing periodicity as that of the accelerators preceding the funnel. Also, instead of conventional deflection systems, we propose to use the properties of a modified RFQ structure to deflect two parallel beams toward each other and to merge them into a single final beam. 1 ref., 3 figs

Noninterceptive transverse-beam measurements

Totally noninterceptive techniques for accurate measurement of transverse beam distributions are required for high-current continuous wave (cw) linacs, such as the Fusion Materials Irradiation Test (FMIT) accelerator. Sensors responding to visible radiation from beam interactions with residual gas and computer algorithms reconstructing spatial and phase space distributions have been implemented. This paper reports on early measurements of the beam from the injector of the prototype FMIT facility at Los Alamos. The first section indicates hardware setup and performance whereas the second section describes the data-processing software. The third section outlines the resultant measurements and further developments are discussed in the fourth section

Noninterceptive transverse beam diagnostics

The transverse emittance properties of a high-current linear accelerator may be measured by using TV cameras sensitive to the visible radiation emitted following beam interactions with residual gas. This paper describes the TV system being used to measure emittances for the Fusion Materials Irradiation Test (FMIT) project

Zeus-2D Simulations of Laser-Driven Radiative Shock Experiments

A series of experiments is underway using the Omega laser to examine radiative shocks of astrophysical relevance. In these experiments, the laser accelerates a thin layer of low- Z material, which drives a strong shock into xenon gas. One-dimensional numerical simulations using the HYADES radiation hydrodynamics code predict that radiation cooling will cause the shocked xenon to collapse spatially, producing a thin layer of high density (i.e., a collapsed shock). Preliminary experimental results show a less opaque layer of shocked xenon than would be expected assuming that all the xenon accumulates in the layer and that the X-ray source is a pure Kα source. However, neither of these assumptions is strictly correct. Here we explore whether radial mass and/or energy transport may be significant to the dynamics of the system. We report the results of two-dimensional numerical simulations using the ZEUS-2D astrophysical fluid dynamics code. Particular attention is given to the simulation method.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/42062/1/10509_2005_Article_3946.pd