{"record":{"author":{"account_ref":null,"orcid":null},"builds_on":[],"content_schema":"pubphys.content.revision/1","content_sha256":"34e4a5a6efcf62376b1c7eb1ef8e9925adaa6b6ddc340b6705965640162d7116","created":"2026-10-15T23:43:22Z","files":[],"origin":{"assisted_by":[],"kind":"seed"},"parents":["ce59fb6cd812fc05906d0c60a71c75ea22bc686bcf38e7c3ef7010834d98ee7b","d96f4dd373bea031deac17c645f7c7f1fe02050e04d9bf09cf1847be1d3faf78"],"salt":"40371aae4b1ff286bfd540fb6e76cf04474406e2b584c1737f03bd82d39d65ac","schema":"pubphys.record/2","site":"pubphys.com","target":null,"type":"revision"},"content":{"answer_type":"yes-no","assisted_by":[],"external_id":"beams.space-charge-halo.integrable-optics-intensity","kind":"well-posed","literature_status":"open","n":"2","parents":[],"plain":"Special magnet arrangements keep particle orbits regular even when they are nonlinear; whether they still help when the beam's own repulsion is included is unknown.","posed_since":"","precise":"Nonlinear integrable lattices of the Danilov-Nagaitsev type preserve two invariants of single-particle transverse motion with large amplitude-dependent tune spread. Determine whether, for a beam with $\\left|\\Delta Q_{\\mathrm{sc}}\\right| \\sim 0.1\\text{-}0.5$, a ring with such an insert shows lower halo growth and loss than an equivalent linear lattice, either through a self-consistent equilibrium that keeps the invariants or through Landau damping of envelope and coherent resonances.","problem_ref":"d96f4dd373bea031deac17c645f7c7f1fe02050e04d9bf09cf1847be1d3faf78","references":"","settled_by":"Self-consistent space-charge simulations and a proton experiment comparing halo and loss for integrable and linear configurations of one ring.","status_note":"","title":"Does nonlinear integrable optics raise the space-charge limit?","topic_ref":null},"attested":{"attestation":{"batch":null,"client_id":null,"id_token_sha256":null,"kind":"platform"},"record_hash":"2836e16fa53352a16acdd1abdddf6ace6f8da721d9562c3d45419092f803ab9c","schema":"pubphys.attested/1"},"envelope":{"attested_hash":"75280e7f6f168fa55c0397e1dd9ba6bc00a0b3ac24b6610a2b6b193c012f714c","platform_signature":{"key_id":"c6afc19b31429869751f06879c75cd64ea92654423d15b44be775bf1310a60da","sig":"1O4eI2_vlGMRLLD0tYJCgyH8NHPGW6BmHKXcER7IlRfs8JxuG9DZKQd6hDEizJZgzWrq0X6gopBDMLimf_x6CQ"},"schema":"pubphys.envelope/1"},"record_hash":"2836e16fa53352a16acdd1abdddf6ace6f8da721d9562c3d45419092f803ab9c","leaf_index":2532}