{"paper":{"title":"A New Source of Millicharged Particles: Secondary Showers in the LHC Forward Absorber","license":"http://creativecommons.org/licenses/by/4.0/","headline":"Secondary production in the LHC TAXN absorber generates a substantial millicharged particle flux that boosts forward detector signals by about 50 percent for light masses.","cross_cats":["hep-ex"],"primary_cat":"hep-ph","authors_text":"Azam Zabihi, Jyotismita Adhikary, Peiran Li, Sebastian Trojanowski, Zhen Liu","submitted_at":"2026-05-13T18:00:03Z","abstract_excerpt":"Millicharged particles (mCPs) are a well-motivated target for far-forward searches at the Large Hadron Collider. We identify and quantify a significant new source of these particles: secondary production in hadronic and electromagnetic showers initiated by energetic neutral particles striking the TAXN absorber. By combining Monte Carlo simulations with \\texttt{Geant4}-based modeling, we show that these secondary cascades yield a substantial mCP flux that complements the primary production from the interaction point. For the proposed FORMOSA detector, this contribution can enhance the expected "},"claims":{"count":4,"items":[{"kind":"strongest_claim","text":"By combining Monte Carlo simulations with Geant4-based modeling, we show that these secondary cascades yield a substantial mCP flux that complements the primary production from the interaction point. For the proposed FORMOSA detector, this contribution can enhance the expected signal yield by approximately 50% for m_χ ≲ 0.1 GeV.","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"The Monte Carlo and Geant4 modeling accurately captures the production rate of millicharged particles inside the hadronic and electromagnetic showers initiated by neutral particles striking the TAXN absorber.","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"Secondary cascades in the TAXN absorber produce a substantial millicharged particle flux that complements primary production and boosts FORMOSA signals by ~50% for m_χ below 0.1 GeV.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"},{"kind":"headline","text":"Secondary production in the LHC TAXN absorber generates a substantial millicharged particle flux that boosts forward detector signals by about 50 percent for light masses.","source":"verdict.pith_extraction.headline","status":"machine_extracted","claim_id":"C4","attestation":"unclaimed"}],"snapshot_sha256":"ea28ad6b0768aadccff1981be8bb7842f672c6fd19a9628e8da72f9cd4145fa5"},"source":{"id":"2605.13964","kind":"arxiv","version":1},"verdict":{"id":"5dffa37d-c197-4576-b508-0d2997c9a6fd","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-15T05:22:03.788904Z","strongest_claim":"By combining Monte Carlo simulations with Geant4-based modeling, we show that these secondary cascades yield a substantial mCP flux that complements the primary production from the interaction point. For the proposed FORMOSA detector, this contribution can enhance the expected signal yield by approximately 50% for m_χ ≲ 0.1 GeV.","one_line_summary":"Secondary cascades in the TAXN absorber produce a substantial millicharged particle flux that complements primary production and boosts FORMOSA signals by ~50% for m_χ below 0.1 GeV.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"The Monte Carlo and Geant4 modeling accurately captures the production rate of millicharged particles inside the hadronic and electromagnetic showers initiated by neutral particles striking the TAXN absorber.","pith_extraction_headline":"Secondary production in the LHC TAXN absorber generates a substantial millicharged particle flux that boosts forward detector signals by about 50 percent for light masses."},"references":{"count":90,"sample":[{"doi":"","year":2012,"title":"Observation of a new boson at a mass of 125 GeV with the CMS experiment at the LHC","work_id":"02ab5f35-5521-45e2-bb51-6c2b69b1c615","ref_index":1,"cited_arxiv_id":"1207.7235","is_internal_anchor":true},{"doi":"","year":2012,"title":"Observation of a new particle in the search for the standard model higgs boson with the atlas detector at the lhc.Physics Letters B2012;716(1):1–29","work_id":"ecf87d7b-ffee-4edd-a7cd-56371de672ff","ref_index":2,"cited_arxiv_id":"1207.7214","is_internal_anchor":true},{"doi":"","year":2020,"title":"Alimena et al.,Searching for long-lived particles beyond the Standard Model at the Large Hadron Collider,J","work_id":"cfd2b757-d725-4c8d-99bb-4a1080b15153","ref_index":3,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2021,"title":"Review of opportunities for new long-lived particle triggers in Run 3 of the Large Hadron Collider","work_id":"ff1b365e-e81d-4612-add7-af24bdf5b7e6","ref_index":4,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2025,"title":"Hayrapetyanet al.(CMS), Dark sector searches with the CMS experiment, Phys","work_id":"9d36c1fd-7dde-4be2-a954-eac2e8511577","ref_index":5,"cited_arxiv_id":"","is_internal_anchor":false}],"resolved_work":90,"snapshot_sha256":"1a62c51ecf99c97156871736cf53000642bdce182ca9e70935fa47940f5f5f93","internal_anchors":28},"formal_canon":{"evidence_count":1,"snapshot_sha256":"ad3b1d54782c182ffef5e15f093aec7979536e2c6e4d921a78050c35dfa6bda9"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}