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Development of Whispering Gallery Mode Polymeric Micro-optical Electric Field Sensors
Published on: January 29, 2013
Wake field in dielectric acceleration structures
1Department of Electrical Engineering, Technion-IIT, Haifa 32000, Israel.
Summary
This study introduces a method to analyze wake fields from point charges in dielectric-lined tunnels. The decelerating force depends on tunnel radius and dielectric properties, stabilizing with distance from the tunnel edge.
Area of Science:
- Electromagnetism
- Particle Accelerators
- Materials Science
Background:
- Charged particle beams interacting with dielectric structures generate wake fields.
- Understanding these wake fields is crucial for accelerator design and beam stability.
- Previous analyses often simplified the surrounding dielectric geometry.
Purpose of the Study:
- To develop a general analytical approach for wake field analysis of a point charge in a vacuum tunnel within a dielectric.
- To derive a quasianalytic expression for the decelerating force.
- To investigate the influence of dielectric reflection characteristics on the wake field.
Main Methods:
- Formulation of a general approach for wake field analysis.
- Development of a quasianalytic expression relating force to dielectric properties and geometry.
- Utilizing simulation results for a simple dielectric structure.
Main Results:
- A quasianalytic expression for the decelerating force was derived.
- Simulations show the decelerating field converges exponentially with distance from the tunnel edge.
- The asymptotic value of the decelerating field is determined by the first dielectric layer.
Conclusions:
- The wake field's dependence on the dielectric structure can be precisely modeled.
- The distance of reflection from the vacuum tunnel edge significantly impacts the wake field.
- The findings are applicable to the design of particle accelerators and beam manipulation systems.
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