The relative center-of-mass energy spread at e+e− colliders is about 10−3, which is much larger than the widths of narrow resonances J/ψ, ψ(2S), Υ(1S), Υ(2S), Υ(3S) mesons, tauonium and some others. It's reduction would significantly increase the resonance production rates and open up great opportunities in the search for new physics. In this paper, we propose a new monochromatization method for colliders with a large crossing angle (which can provide a high luminosity). The contribution of the beam energy spread to the spread of the center-of-mass energy is canceled by introducing an appropriate energy-angle correlation at the interaction point; σW/W∼(0.5−1)10−5 appears possible.
@article{arxiv.2008.13668,
title = {Monochromatization of $e^+e^-$ colliders with a large crossing angle},
author = {V. I. Telnov},
journal= {arXiv preprint arXiv:2008.13668},
year = {2025}
}