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arXiv · 2510.09070

Observation of a pseudoscalar excess at the $t\bar{t}$ threshold

Alexander Grohsjean
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Abstract

The CMS Collaboration recently observed a pseudoscalar excess of top quark-antiquark ($t\bar{t}$) events near the production threshold. One possible interpretation involves the formation of a short-lived quasi-bound state of $t\bar{t}$. This proceeding summarizes the first presentation of the results at the 59th Rencontres de Moriond and outlines its potential implications.

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Alexander Grohsjean. 2025-10-10. Observation of a pseudoscalar excess at the $t\bar{t}$ threshold. https://arxiv.org/abs/2510.09070

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