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Updated: Dec 20, 2025
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Experimental Methods for Spin- and Angle-Resolved Photoemission Spectroscopy Combined with Polarization-Variable Laser
Published on: June 28, 2018
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Doing Spin Physics with Unpolarized Particles
Igor P Ivanov1, Nikolai Korchagin2, Alexandr Pimikov3
1CFTP, Instituto Superior Tecnico, Universidade de Lisboa, Lisbon 1049-001, Portugal.
Physical Review Letters
|May 30, 2020
Summary
Twisted particles, with helical wavefronts and orbital angular momentum, offer new insights in particle physics. Collisions of twisted photons and electrons can reveal novel spin and parity information from inclusive cross sections.
Area of Science:
- Particle Physics
- Quantum Optics
- High-Energy Physics
Background:
- Twisted particles possess helicoidal wavefronts and nonzero orbital angular momentum.
- Experimental demonstrations exist for twisted photons and electrons.
- These states offer a new degree of freedom for particle interactions.
Purpose of the Study:
- To theoretically investigate resonance production in twisted photon collisions and twisted electron-positron annihilation.
- To explore the potential of these processes as novel probes of spin and parity.
- To analyze the impact of nonzero orbital angular momentum on symmetry breaking.
Main Methods:
- Theoretical analysis of resonance production in twisted particle collisions.
- Investigation of fully inclusive cross sections with unpolarized initial particles.
- Examination of symmetry breaking due to initial state angular momentum.
Main Results:
- Resonance production in twisted particle collisions provides novel spin and parity-sensitive observables.
- Nonzero angular momentum breaks left-right symmetry, even with unpolarized particles.
- Achieved nearly 100% polarization of vector mesons in twisted electron-positron annihilation.
Conclusions:
- Twisted particle collisions offer a new, powerful tool for probing fundamental particle properties.
- The control over vector meson polarization in twisted e+e- annihilation is demonstrated.
- This research opens new avenues for exploring particle physics with twisted states.
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