{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"c2b84e7508f6215d7dad61ecfe1aa5a7e53948cab513132b3a0d2f0b192ef16e","created":"2026-10-03T07:17:54Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"c24bf5643cdf91078eaea2b17e3e79e6e8157283f202e7579dba78ef061ab0b3","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"identification","assisted_by":[],"external_id":"astro.cosmic-ray-antimatter.antihelium-candidates","kind":"well-posed","literature_status":"open","n":"1","parents":[],"plain":"The AMS-02 detector team has spoken of a handful of possible antihelium nuclei, which ordinary cosmic-ray collisions should almost never make. The events have not been published in a refereed paper.","posed_since":"","precise":"AMS-02 has reported in conference talks a few candidate antihelium-3 and antihelium-4 events, while predicted secondary production gives far less than one antihelium-4 event in the exposure. Decide whether any candidate is a genuine antinucleus rather than a misidentified background, and if so identify its source (dark matter, antimatter domains, or underestimated coalescence production).","problem_ref":null,"references":"","settled_by":"A refereed AMS-02 analysis with background estimates, or independent detection by a separate experiment such as the GAPS balloon instrument.","status_note":"As of 2026 the candidates remain unpublished in the refereed literature.","title":"Are the AMS-02 antihelium candidate events real?","topic_ref":"9361a52640d12aea0c06eba8ab45c71de10728afb1ce58839faac9301aaf079e"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"41b2a3f41e2f357c4bd5c88dbb6ea6ae207498962a3a11ed57f9d550556544ad","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"5939c7fae80f64ad0af7edca82547bc83b6b60bb8bca12eb2b0be077111d8d3a","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"_QPFlfVqxr40qyY8MYE7OaKmWosjuXXF6OzJ-O1qV5LxsIusBNLzkfWGJ5pJb_q_u6yX_IOAsSE2lpdn6ZWMAQ"},"schema":"pubphys.envelope/1"},"record_hash":"41b2a3f41e2f357c4bd5c88dbb6ea6ae207498962a3a11ed57f9d550556544ad","leaf_index":507}