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Updated: Jul 13, 2026
14:11
Quantification of Hydrogen Concentrations in Surface and Interface Layers and Bulk Materials through Depth Profiling with Nuclear Reaction Analysis
Published on: March 29, 2016
One-dimensional beam ordering of protons in a storage ring.
T Shirai1, M Ikegami, S Fujimoto
1Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011, Japan. shirai@kyticr.kuicr.kyoto-u.ac.jp
Physical Review Letters
|August 7, 2007
Summary
Proton ordering was observed at the S-LSR storage ring. Electron cooling induced abrupt changes in proton momentum spread and noise, revealing a transition temperature crucial for this particle ordering.
Area of Science:
- Particle physics
- Beam dynamics
- Condensed matter physics
Background:
- Proton ordering is a phenomenon of interest in particle physics.
- Understanding particle beam behavior is crucial for accelerator science.
Purpose of the Study:
- To investigate proton ordering phenomena.
- To observe the effects of electron cooling on proton beams.
Main Methods:
- Experiments conducted at the S-LSR storage ring.
- Utilized electron cooling with varying electron currents (25, 50, 100 mA).
- Measured momentum spread and Schottky noise power.
Main Results:
- Observed abrupt jumps in proton momentum spread and Schottky noise power at ~2000 particles.
- Determined transition temperatures of 0.17 meV (longitudinal) and 1 meV (transverse).
- Proton beam transverse temperature was significantly lower than electron temperature during ordering.
Conclusions:
- Electron cooling is effective in inducing proton ordering.
- The observed transition temperature is a key parameter in proton beam ordering.
- The lower transverse temperature of the proton beam relative to electrons is essential for ordering.
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