Final focusing of intense ion beams with radially nonuniform current density z discharges

Journal Article · Fri Dec 01 04:00:00 EST 1989 · Physics of Fluids B: Plasma Physics; (USA)

DOI:https://doi.org/10.1063/1.859198· OSTI ID:5174314

Watrous, J J; Ottinger, P F ^[1]

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1. Plasma Technology Branch, Naval Research Laboratory, Washington, DC 20375 (USA)

The spot size and focal length of a one-eighth betatron wavelength final focusing cell with a nonuniform current density distribution are predicted. The final focusing cell is modeled with an azimuthal magnetic field distribution that varies as {ital r}{sup {ital N}}. A Lie transform method is used to determine the behavior of the ion beam as it passes through the focusing cell. The analysis indicates that a final focusing cell with a current density distribution that is strongly concentrated at the channel edge focuses the beam much less efficiently than a channel with a uniform current density distribution, and provides a scaling relation for the focused beam radius: {ital r}{sub foc} {proportional to}{ital r}{sub {ital c}} ({ital I}{sub {ital c}}/ {ital I}{sub {ital f}}){sup 1/2{ital N}}, where {ital r}{sub {ital c}} is the unfocused beam radius, {ital I}{sub {ital f}} is the discharge current in the focusing cell, and {ital I}{sub {ital c}} is the discharge current in the transport channel.

• OSTI ID: 5174314
• Journal Information: Physics of Fluids B: Plasma Physics; (USA), Journal Name: Physics of Fluids B: Plasma Physics; (USA) Vol. 1:12; ISSN 0899-8221; ISSN PFBPE
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
700208* -- Fusion Power Plant Technology-- Inertial Confinement Technology
ACCELERATORS
AZIMUTH
BEAM-PLASMA SYSTEMS
BEAMS
BETATRONS
BRIGHTNESS
CONFINEMENT
CURRENT DENSITY
CYCLIC ACCELERATORS
FOCUSING
INERTIAL CONFINEMENT
ION BEAMS
LIE GROUPS
MAGNETIC FIELDS
OPTICAL PROPERTIES
PHYSICAL PROPERTIES
PLASMA CONFINEMENT
PULSES
SYMMETRY GROUPS
TRANSFORMATIONS