The Effect of an Under-Dense Plasma Density Gradient on the Backstreaming Ion Mechanism

George J. Caporaso

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The Effect of an Under-Dense Plasma Density Gradient on the Backstreaming Ion Mechanism

George J. Caporaso

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Abstract

The space charge limited emission of ions from a target in the focus of an intense relativistic electron beam is studied analytically for the case of a spatially varying target density profile. In particular, the emission in the presence of an under-dense plasma shelf in contact with the solid density target dramatically differs from the case of an abrupt solid-vacuum boundary. It is found that an under-dense gradient scale length several times that of the beam radius at the focus reduces the emission by at least an order of magnitude over that to be expected from a solid-vacuum boundary.

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George J. Caporaso. 2000-10-03. The Effect of an Under-Dense Plasma Density Gradient on the Backstreaming Ion Mechanism. https://arxiv.org/abs/physics/0010009

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