{"paper":{"title":"$\\Xi_{cc}^{++}-\\Xi_{cc}^{+}$ Transitions as a Two-Charm-Selective Portal to Ultra-Low-$Q$ Charged Currents","license":"http://creativecommons.org/licenses/by-sa/4.0/","headline":"","cross_cats":["hep-ex"],"primary_cat":"hep-ph","authors_text":"Yong Du","submitted_at":"2026-06-18T09:29:47Z","abstract_excerpt":"The recent LHCb observation of $\\Xi_{cc}^{+}$ opens the ultra-low-$Q$ transition $\\Xi_{cc}^{++}\\to\\Xi_{cc}^{+}$ as an experimentally motivated null test of charged-current new physics. Our two- and three-body analyses show sensitivity to effective baryon-level couplings of $\\mathcal{O}(10^{-6}-10^{-7})$ for MeV-scale recoil momenta. We establish a practical no-go result for a universal light charged scalar $\\phi^+$: with a first-generation $\\phi^+\\bar u d$ coupling, existing electroweak-precision and beta-decay constraints are parametrically stronger than the projected LHCb sensitivity. We the"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2606.19991","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/2606.19991/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"}