Lighthyphen;ion inertial confinement fusion requires beam transport over distances of a few meters for isolation of the diode hardware from the target explosion and for power compression by timehyphen;ofhyphen;flight bunching. This paper evaluates ballistic transport of lighthyphen;ion beams focused by a solenoidal lens. The ion beam is produced by an annular magnetically insulated diode and is extracted parallel to the axis by appropriate shaping of the anode surface. The beam propagates from the diode to the solenoidal lens in a fieldhyphen;free drift region. The lens alters the ion trajectories such that the beam ballistically focuses onto a target while propagating in a second fieldhyphen;free region between the lens and the target. Ion orbits are studied to determine the transport efficiency eegr;t(i.e., the fraction of the beam emitted from the diode which hits the target) under various conditions relevant to lighthyphen;ion inertial confinement fusion. Analytic results are given for a sharp boundary, finite thickness solenoidal lens configuration, and numerical results are presented for a more realistic lens configuration. From the analytic results, it is found that eegr;tcan be in the range of 75percnt;ndash;100percnt; for parameter values that appear to be achievable. Numerical results show that using a more realistic magnetichyphen;field profile for the lens yields similar values of eegr;tfor small radius diodes but significantly reduced values of eegr;tfor large radius diodes. This reduction results from the radial gradient in the focusing field at larger radius.
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