Liquid-film stripper for high-intensity heavy-ion beams

Electron strippers are widely used in heavy ion accelerators such as tandem Van de Graaff generators and heavy ion linacs. The SuperHILAC at Lawrence Berkeley Laboratory, employs a fluorocarbon oil vapor stripper at 113 keV/A for its high intensity injector ABEL, while after acceleration to 1.199 MeV/A a 35 ..mu..g/cm/sup 2/ carbon foil stripper is used. At present, the lifetime of these foils is about 1 hour for an /sup 40/Ar beam of approx. 1 ..mu..A average particle current. With higher intensity high mass (100 less than or equal to A less than or equal to 238) beams available from ABEL injector the lifetime is expected to drop drastically and might be as low as one minute. A different approach to solve the stripper foil lifetime problem uses a thin free standing oil film spun from the edge of a sharp-edged rotating disc touching the surface of an oil reservoir. Areas of about 10 cm/sup 2/ with areal densities down to 20 ..mu..g/cm/sup 2/ have been reported. The work described here is based on the same concept, and produces a constantly regenerated, stable, free standing oil film of appropriate thickness for use at the SuperHILAC

Superconducting Super Collider reference design magnets Style ``D`` cost design. Contents

This note describes a ``Design D`` style superconducting dipole magnet being studied for the SSC. This particular version of the design is being developed for initial manufacturing studies and reference cost estimate comparison. The main bending magnets are being considered in detail because they are the most costly elements of the machine and, therefore, require considerable R&D to verify performance and to develop the most economical design. Also to be described (but not in this note) are the quadrupole magnets, field correction magnets, and certain special magnets

MECHANICAL DESIGN OF A HEAVY ION RFQ

The mechanical design and construction of a 199.3 MHz heavy ion RFQ for charge states q/A as low as 0.14 is described. The vane supports and positioning adjustments are significant features of this design. They provide the capability of achieving the precision vane alignment required. The maximum difference between calculated and measured apertures between the vanes is 0.0035 inches, and the average difference is 0.0010 inches. Various important aspects of the design and construction including material selection and plating, RF joints, thermal loading and vacuum system are described. Assembly techniques, methods of mechanical measurement, alignment and structure stability are discussed in detail