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Updated: Jul 7, 2026
08:36
An Atmospheric Pressure Plasma Setup to Investigate the Reactive Species Formation
Published on: November 3, 2016
Ultrarelativistic-positron-beam transport through meter-scale plasmas
M J Hogan1, C E Clayton, C Huang
1Stanford Linear Accelerator Center, Stanford, California 94309, USA.
Physical Review Letters
|June 6, 2003
Summary
This study is the first to examine dynamic transverse forces on ultrarelativistic positron beams in long plasmas. Researchers observed beam focusing and force variations along the bunch, with simulations revealing aberration and emittance degradation.
Area of Science:
- Plasma physics
- Beam physics
Background:
- Understanding beam-plasma interactions is crucial for particle accelerators.
- Previous studies have not fully explored dynamic transverse forces in underdense plasmas.
Purpose of the Study:
- To investigate the dynamic transverse forces acting on an ultrarelativistic positron beam within a long plasma.
- To analyze the focusing effects and force variations along the positron bunch.
Main Methods:
- Experimental study using a 28.5 GeV positron beam and a 1.4 m plasma.
- Time-resolved beam profile measurements.
- Computer simulations to model beam-plasma interactions.
Main Results:
- Observed focusing of the positron beam after traversing the plasma.
- Demonstrated that transverse forces vary along the positron bunch length (approx. 12 ps).
- Force strength was found to be dependent on plasma density.
Conclusions:
- The study provides the first experimental evidence of dynamic transverse forces in this regime.
- Simulations confirmed longitudinal aberrations and identified emittance degradation mechanisms.
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