Ion-Hose Instability in a High Current, Long-Pulse Accelerator

Astronomy and Astrophysics – Astrophysics

Scientific paper

Rate now

  [ 0.00 ] – not rated yet Voters 0   Comments 0

Details

Scientific paper

The ion-hose instability is a transverse electrostatic instability which occurs on electron beams in the presence of a low-density ion channel. In the DARHT-2 accelerator, the 2 kA, 2 μsec beam pulse produces an ion channel through impact ionization of the residual background gas (1.5× 10-7 torr average). A calculation of the linear growth by R. J. Briggs indicated that the instability could be strong enough to affect the radiographic application of DARHT, which requires that transverse oscillations be small compared to the beam radius. We present semi-analytical theory and 3-D particle-in-cell simulations (using the LSP code) of the linear and non-linear growth of the instability, including the effects of the temporal change in the ion density, spatially decreasing beam radius etc. We find that the number of e-foldings for a particular beam slice is given approximately by the analytic expression for a uniform channel using an average value for the channel density. Hence, in the linear regime, the number of e-foldings increases linearly from head to tail of the beam pulse. We also find that growth is suppressed by non-linear effects at relatively small amplitudes of the electron beam. This is because the ion oscillation amplitude is several times larger than that of the beam, allowing non-linear effects to come into play.

No associations

LandOfFree

Say what you really think

Search LandOfFree.com for scientists and scientific papers. Rate them and share your experience with other people.

Rating

Ion-Hose Instability in a High Current, Long-Pulse Accelerator does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.

If you have personal experience with Ion-Hose Instability in a High Current, Long-Pulse Accelerator, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Ion-Hose Instability in a High Current, Long-Pulse Accelerator will most certainly appreciate the feedback.

Rate now

     

Profile ID: LFWR-SCP-O-1536917

  Search
All data on this website is collected from public sources. Our data reflects the most accurate information available at the time of publication.