Kinematic surprises in twisted particle collisions

TL;DR

This paper explores the unique kinematic phenomena in collisions involving twisted particles, revealing new observables and capabilities such as interference patterns and automatic resonance separation, which are not possible in traditional plane-wave collisions.

Contribution

It provides a detailed analysis of the kinematic features of twisted particle annihilation, highlighting novel effects like interference fringes and built-in mass spectrometry.

Findings

New momentum space dimension in twisted annihilation

Interference fringes in cross section as a function of energy

Automatic separation of multiple resonances by mass

Abstract

"Twisted particles" refer to non-plane-wave states of photons, electrons, hadrons, or any other particle which carry non-zero, adjustable orbital angular momentum with respect to their average propagation direction. Twisted photons and electrons have already been experimentally demonstrated, and one can expect creation of twisted states of other particles in future. Such states can be brought in collisions, offering a completely new degree of freedom in collider experiments and, especially, a novel tool for hadronic physics. We recently showed that $2 \to 1$ processes with two twisted particles such as resonance production in twisted $e^+e^-$ annihilation give access to observables which are difficult or impossible to probe in the usual plane-wave collisions. In this paper, we discuss in detail surprising kinematic features of this process, focusing on spinless particle annihilation. They include (1) a new dimension in the final momentum space available in twisted annihilation, (2) interference fringes emerging in the cross section as a function of the total energy, and (3) the built-in mass spectrometric capability of this process, that is, simultaneous production and automatic angular separation of several resonances with different masses in monochromatic twisted particle annihilation experiment running at fixed energy. All these features cannot be obtained in the usual plane wave collision setting.