{"paper":{"title":"Ionization Structure and Metal Enrichment of the Galactic Center Minispiral Observed with JWST","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"JWST data show the Galactic Center Minispiral gas has 1-2.5 solar metallicity, ionized mainly by Wolf-Rayet stars with extra hard radiation in compact structures.","cross_cats":[],"primary_cat":"astro-ph.GA","authors_text":"Daryl Haggard, Giacomo Principe, Howard A. Smith, Joey Neilsen, Joseph L. Hora, Joseph M. Michail, Mayura Balakrishnan, Nadeen B Sabha, Nicole M Ford, Sebastiano D. von Fellenberg, S. P. Willner, Tamojeet Roychowdhury, Yuzhu Cui, Zach Sumners","submitted_at":"2026-05-13T18:06:25Z","abstract_excerpt":"Sgr A* is the nearest quiescent supermassive black hole, and its proximity offers a unique opportunity to study its surrounding fuel supply. We leverage extensive spatial and spectroscopic information provided by the \\jwst/MIRI MRS instrument to disentangle mid-infrared ionized gas structures in the central 0.1 parsec of the Galaxy. The Galactic Minispiral's Bar and Northern Arm are revealed by their distinct morphological and kinematic signatures. Several compact ($<1$\\arcsec) gas structures including X7 also appear within $\\sim 0.05$ parsec of Sgr A* in the plane of the sky, moving with blue"},"claims":{"count":4,"items":[{"kind":"strongest_claim","text":"The Minispiral gas metallicity is ∼1-2.5 Z⊙, with a Wolf-Rayet star-driven ionizing radiation field, and significant nickel and iron dust destruction. Increased flux at energies ≳41 eV suggests that the compact gas structures experience an additional harder ionizing radiation source, which is most likely driven by localized fast radiative shocks from stellar winds, a hypothetical Sgr A* outflow, and/or interactions with the ambient medium.","source":"verdict.strongest_claim","status":"machine_extracted","claim_id":"C1","attestation":"unclaimed"},{"kind":"weakest_assumption","text":"The analysis assumes that standard photoionization models and line ratio diagnostics accurately separate the contributions from Wolf-Rayet stars, shocks, and possible Sgr A* outflows without significant unaccounted-for effects from dust geometry or additional radiation sources.","source":"verdict.weakest_assumption","status":"machine_extracted","claim_id":"C2","attestation":"unclaimed"},{"kind":"one_line_summary","text":"JWST MIRI MRS observations show the Galactic Center Minispiral gas has 1-2.5 solar metallicity, Wolf-Rayet driven ionization, significant Ni and Fe dust destruction, and harder radiation in compact structures near Sgr A*.","source":"verdict.one_line_summary","status":"machine_extracted","claim_id":"C3","attestation":"unclaimed"},{"kind":"headline","text":"JWST data show the Galactic Center Minispiral gas has 1-2.5 solar metallicity, ionized mainly by Wolf-Rayet stars with extra hard radiation in compact structures.","source":"verdict.pith_extraction.headline","status":"machine_extracted","claim_id":"C4","attestation":"unclaimed"}],"snapshot_sha256":"49402cb3c128db08cb09f63d42e3cfe09c0e7c1864a99f1f1cb22168c2357f9b"},"source":{"id":"2605.13995","kind":"arxiv","version":1},"verdict":{"id":"c521878c-cde9-439d-9093-37f8d9bef6fc","model_set":{"reader":"grok-4.3"},"created_at":"2026-05-15T02:11:40.745924Z","strongest_claim":"The Minispiral gas metallicity is ∼1-2.5 Z⊙, with a Wolf-Rayet star-driven ionizing radiation field, and significant nickel and iron dust destruction. Increased flux at energies ≳41 eV suggests that the compact gas structures experience an additional harder ionizing radiation source, which is most likely driven by localized fast radiative shocks from stellar winds, a hypothetical Sgr A* outflow, and/or interactions with the ambient medium.","one_line_summary":"JWST MIRI MRS observations show the Galactic Center Minispiral gas has 1-2.5 solar metallicity, Wolf-Rayet driven ionization, significant Ni and Fe dust destruction, and harder radiation in compact structures near Sgr A*.","pipeline_version":"pith-pipeline@v0.9.0","weakest_assumption":"The analysis assumes that standard photoionization models and line ratio diagnostics accurately separate the contributions from Wolf-Rayet stars, shocks, and possible Sgr A* outflows without significant unaccounted-for effects from dust geometry or additional radiation sources.","pith_extraction_headline":"JWST data show the Galactic Center Minispiral gas has 1-2.5 solar metallicity, ionized mainly by Wolf-Rayet stars with extra hard radiation in compact structures."},"references":{"count":124,"sample":[{"doi":"10.1086/589652","year":2008,"title":"Allen, M. G., Groves, B. A., Dopita, M. A., Sutherland, R. S., & Kewley, L. J. 2008, ApJS, 178, 20, doi: 10.1086/589652","work_id":"3a857afa-64fd-4ef0-a528-452b98cafbbf","ref_index":1,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"10.1051/0004-6361/202245001","year":2023,"title":"Anastasopoulou, K., Ponti, G., Sormani, M. C., et al. 2023, A&A, 671, A55, doi: 10.1051/0004-6361/202245001","work_id":"b037d137-15bd-4068-8b1d-432f9e75f953","ref_index":2,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"10.1007/s00159-022-00146-x","year":2023,"title":"2023, A&A Rv, 31, 1, doi: 10.1007/s00159-022-00146-x","work_id":"0891a63a-a2c2-4f62-a72d-6a3e37762502","ref_index":3,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"10.1051/0004-6361/202346489","year":2023,"title":"Argyriou, I., Glasse, A., Law, D. R., et al. 2023, A&A, 675, A111, doi: 10.1051/0004-6361/202346489","work_id":"496b7b51-6a41-44eb-afae-83515cac3fb9","ref_index":4,"cited_arxiv_id":"","is_internal_anchor":false},{"doi":"10.1051/0004-6361/202140445","year":2021,"title":"The chemical make-up of the Sun: A 2020 vision","work_id":"25e49e0c-1639-4c85-a0a5-c450c0de63a8","ref_index":5,"cited_arxiv_id":"2105.01661","is_internal_anchor":true}],"resolved_work":124,"snapshot_sha256":"026d5bc425841f059bfac8e0c6228dacf1fdce596ce16897f896e9dedb6d8aac","internal_anchors":2},"formal_canon":{"evidence_count":2,"snapshot_sha256":"fe59114f7a83c14f1b4d4aed517ffb089ef0142aaa7a69b2213b5ab38e7b3f20"},"author_claims":{"count":0,"strong_count":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"builder_version":"pith-number-builder-2026-05-17-v1"}