Measurement of electron clouds in large accelerators by microwave dispersion
S De Santis1, J M Byrd, F Caspers
1Ernest Orlando Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, CA 94720, USA.
Physical Review Letters
|March 21, 2008
Summary
A new method measures electron cloud density in accelerator pipes using wave phase shifts. This technique was successfully applied to a 50-meter section of the PEP-II collider
Area of Science:
- Particle Accelerator Physics
- Plasma Physics
Background:
- Electron clouds in accelerator beam pipes limit high-current operation.
- Probing electron cloud density over long distances is challenging.
Purpose of the Study:
- To develop a novel technique for directly measuring electron cloud density.
- To apply this technique to a significant section of an operational accelerator.
Main Methods:
- Developed a method utilizing the phase shift of a transmitted TE wave.
- Measured the phase shift over a 50-meter section of the accelerator beam pipe.
Main Results:
- Successfully measured the average electron cloud density.
- Demonstrated the technique's applicability in a real-world accelerator environment (PEP-II collider).
Conclusions:
- The novel phase shift technique provides a direct and effective means to measure electron cloud density.
- This method overcomes limitations in probing electron clouds over substantial accelerator lengths.
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