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arXiv · 2506.20975

You never have enough J/$\psi$ events: the case for a J/$\psi$ factory

Abstract

In a talk at an IHEP-Beijing symposium celebrating the 50th anniversary of the discovery of the J/$\psi$, I reminisced about some of the interesting phenomena that were observed in J/$\psi$ decays in the BES, BESII, and BESIII detectors during the 35 year long BES experimental program. The three order of magnitude increase in the J/$\psi$ event samples and the improved detector capabilities that occurred during this time led to a persistent series of interesting discoveries and new insights. As more J/$\psi$ events were collected, the scientific interest in them increased and the breadth of physics topics that are addressed by them expanded. In addition, I speculated on what might happen if, in the next few decades, the magnitude of J/$\psi$ data samples and the detector capabilities continued to increase at similar paces. In particular, I emphasize the possibilities of searches for CP violation in strange hyperon decays and testing the CPT~theorem with strangeness-tagged neutral kaon decays.

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Stephen Lars Olsen. 2025-06-26. You never have enough J/$\psi$ events: the case for a J/$\psi$ factory. https://arxiv.org/abs/2506.20975

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