{"paper":{"title":"Heavy quarkonia and new hadrons with two heavy quarks","license":"http://creativecommons.org/publicdomain/zero/1.0/","headline":"","cross_cats":["hep-ph"],"primary_cat":"hep-ex","authors_text":"Chang-Zheng Yuan, Yuping Guo","submitted_at":"2025-08-28T11:20:00Z","abstract_excerpt":"We give a pedagogical introduction to heavy quarkonia -- bound states of a heavy quark and its antiquark (e.g., charmonium $c\\bar{c}$, bottomonium $b\\bar{b}$) -- as well as to the exotic hadrons containing two heavy quarks that have been discovered since 2003. The review covers the foundational discoveries ($J/\\psi$ and $\\Upsilon$), basic properties, spectroscopy interpreted via potential models, production mechanisms at colliders, and decay modes. A significant focus is placed on the so-called ``$XYZ$\" states -- particles like the $X(3872)$, $Y(4260/4230)$, $Z_c(3900)$, and $P_c$ -- whose pro"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2508.20667","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2508.20667/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","internal_anchors":0},"formal_canon":{"evidence_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}