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arXiv · 2002.01703

Twisted particle collisions: a new tool for spin physics

Igor P. Ivanov·Nikolai Korchagin·Alexandr Pimikov·Pengming Zhang
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Abstract

Collisions of twisted particles --- that is, non-plane-wave states of photons, electrons, or any other particle, equipped with a non-zero orbital angular momentum (OAM) with respect to its propagation direction --- offer novel ways to probe particle structure and interactions. In the recent paper \cite{Ivanov:2019vxe}, we argued that resonance production in twisted photon collisions or twisted $e^+e^-$ annihilation gives access to parity- and spin-sensitive observables in inclusive cross sections, even when the initial particles are unpolarized. Here, we explore these features in detail, providing a qualitative picture and illustrating it with numerical examples. We show how one can detect parity-violating effects in collisions of unpolarized twisted photons and how one can produce almost $100\%$ polarized vector mesons in unpolarized twisted $e^+e^-$ annihilation. These examples highlight the unprecedented level of control over polarization offered by twisted particles, impossible in the usual plane wave collisions.

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Igor P. Ivanov, Nikolai Korchagin, Alexandr Pimikov, Pengming Zhang. 2020-02-05. Twisted particle collisions: a new tool for spin physics. https://doi.org/10.1103/physrevd.101.096010

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