{"paper":{"title":"Phase spirals induced by the gas warp","license":"http://creativecommons.org/licenses/by/4.0/","headline":"Irregular gas accretion along the galactic warp induces global, long-lived phase spirals in the stellar disc.","cross_cats":[],"primary_cat":"astro-ph.GA","authors_text":"Anthony G. A. Brown, Shuyu Wang, Tigran Khachaturyants, Victor P. Debattista","submitted_at":"2026-04-08T09:22:55Z","abstract_excerpt":"The discovery of the phase space spirals in the Solar neighborhood in Gaia Data Release 2 has prompted various attempts to understand their origin. A source of bending waves, which has been neglected as a cause of the phase spiral, is irregular gas inflow along the warp. We aim to study whether perturbations by the gas warp could induce phase spirals. Accounting for this additional formation scenario for phase spirals could improve our current understanding of the perturbation history of the Milky Way disc. We use two N-body + SPH (Smooth Particle Hydrodynamics) simulations of an isolated gala"},"claims":{"count":4,"items":[{"kind":"strongest_claim","text":"We conclude that phase spirals can be induced by the irregular gas accretion along the warp. These phase spirals occur globally and are long-lived.","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"The isolated-galaxy N-body+SPH model with imposed warp and gas inflow sufficiently captures the relevant physics and timescales of the real Milky Way disc so that the detected spirals are not simulation artifacts.","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"N-body and SPH simulations show that gas accretion along a galactic warp can generate global, long-lived phase spirals in the stellar disc with amplitudes comparable to those observed by Gaia.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"},{"kind":"headline","text":"Irregular gas accretion along the galactic warp induces global, long-lived phase spirals in the stellar disc.","source":"verdict.pith_extraction.headline","status":"machine_extracted","claim_id":"C4","attestation":"unclaimed"}],"snapshot_sha256":"9236ac3c2a3e35ae9dbf5712f0e8c18a1ac18b261a4775afc4ae6fd53bdd743b"},"source":{"id":"2604.06862","kind":"arxiv","version":1},"verdict":{"id":"41cd7a5c-9e2e-46bb-bc06-170dbcde6a94","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-10T18:26:18.111385Z","strongest_claim":"We conclude that phase spirals can be induced by the irregular gas accretion along the warp. These phase spirals occur globally and are long-lived.","one_line_summary":"N-body and SPH simulations show that gas accretion along a galactic warp can generate global, long-lived phase spirals in the stellar disc with amplitudes comparable to those observed by Gaia.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"The isolated-galaxy N-body+SPH model with imposed warp and gas inflow sufficiently captures the relevant physics and timescales of the real Milky Way disc so that the detected spirals are not simulation artifacts.","pith_extraction_headline":"Irregular gas accretion along the galactic warp induces global, long-lived phase spirals in the stellar disc."},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2604.06862/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"references":{"count":49,"sample":[{"doi":"","year":2023,"title":"J., & Bensby, T","work_id":"176b15b7-c7f9-416b-af9b-bea0f4cd9dc7","ref_index":1,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2024,"title":"J., & Bensby, T","work_id":"1b033028-03fe-4abd-a3a9-a0c16b45164b","ref_index":2,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2018,"title":"2018, Nature, 561, 360","work_id":"e674e7b3-574a-4ae7-a211-082b1e5ef6cc","ref_index":3,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2023,"title":"2023, A&A, 673, A115","work_id":"3889496e-3f7a-4908-9cfd-ab2f43e7420f","ref_index":4,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"","year":2025,"title":"Asano, T., Fujii, M. S., Baba, J., Portegies Zwart, S., & Bédorf, J. 2025, A&A, 700, A109 Astropy Collaboration, Price-Whelan, A. M., Sip˝ocz, B. M., et al. 2018, AJ, 156, 123 Astropy Collaboration, R","work_id":"30e06de8-886f-4119-b35c-3958b6b58162","ref_index":5,"cited_arxiv_id":"","is_internal_anchor":false}],"resolved_work":49,"snapshot_sha256":"192382627989a8b204f775fef0f66513e632cd0cc3de0c3750fa9fd76bd90be0","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"}