High Spin-Flip Efficiency at 255 GeV for Polarized Protons in a Ring With Two Full Siberian Snakes

Area of Science:

• Particle Physics
• Accelerator Physics
• High-Energy Physics

Background:

• Spin-polarized proton beams are crucial for reducing systematic errors in particle collision experiments.
• Previous spin-flipping techniques were effective at low energies (< 2 GeV) but failed at high energies due to spin tune spread and resonance issues.

Purpose of the Study:

• To develop and test an effective spin-flipping method for high-energy polarized proton colliders.
• To overcome limitations of single-magnet flippers in the presence of Siberian snakes and large spin tune spreads.

Main Methods:

• Utilized a sophisticated nine-dipole magnet spin flipper.
• Implemented a specialized optics configuration to minimize spin tune spread.
• Conducted experiments at the Brookhaven National Laboratory Relativistic Heavy Ion Collider (RHIC).

Main Results:

• Achieved a measured spin-flip efficiency of 97% at both 24 GeV and 255 GeV.
• Demonstrated the successful operation of the nine-magnet spin flipper in a high-energy collider environment.
• Validated the effectiveness of the special optics choice in managing spin tune spread.

Conclusions:

• A nine-magnet spin flipper is a viable and efficient solution for spin flipping in high-energy polarized proton colliders.
• This technology significantly advances the capability to control proton spin, enabling more precise experiments.
• The results pave the way for improved systematic error reduction in future high-energy physics research.