{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"cb0689a00cb391ea805e601ca96bfd9cb43f71338f3e547ee21f8d75f90c9118","created":"2026-10-03T07:17:56Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["5475cf5dc5b1a72283d26dc95dc6e00d7ea4e00096a7c6492e409a1816eeb011"],"salt":"d2b632a0587f22b7a1fcf223204f1ce2ceb7a2786fe94e5b02d232802a38de59","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"value","assisted_by":[],"external_id":"beams.space-charge-halo.max-tune-shift-ring","kind":"well-posed","literature_status":"open","n":"1","parents":[],"plain":"Rings tolerate only a limited spread of particle oscillation frequencies caused by space charge before losses grow; this limit is known only empirically.","posed_since":"","precise":"High-intensity synchrotrons operate with incoherent space-charge tune shift $\\left|\\Delta Q_{\\mathrm{sc}}\\right|$ up to approximately 0.2-0.5 over storage times of 1e3 to 1e5 turns. Derive, from the resonance structure of a given lattice and the periodic resonance crossing caused by synchrotron motion in a bunched beam, the maximal $\\left|\\Delta Q_{\\mathrm{sc}}\\right|$ compatible with emittance growth below 10 percent and loss below 1e-3 over $N$ turns, and compare with CERN PS and SPS, J-PARC and GSI SIS18 data.","problem_ref":null,"references":"","settled_by":"A scaling law or simulation that matches measured limits in at least three rings with differing lattices and storage times.","status_note":"","title":"Maximum tolerable space-charge tune shift in synchrotrons","topic_ref":"416111fd7e6fee07d8da591a9ff1426619f087a5ba70068946ba198ef0a5a6c3"},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"cff00ad4b461f256f528025a48cf605d41bcdf28b97a318063144f7456c27318","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"acc1c25aaafd450b44919018d42c2c31ae019df2ac6cc5aed33e7c193443f06c","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"XQwsSkotCDTBQn9jWxupbpzyr4pmFLIE1k59mSi3nbXm5Grqzv1_lhDxqnXhYXXFVpSjwInJcEJjjrmkblZlCw"},"schema":"pubphys.envelope/1"},"record_hash":"cff00ad4b461f256f528025a48cf605d41bcdf28b97a318063144f7456c27318","leaf_index":702}