{"paper":{"title":"Testing General Relativity with the Black Hole Shadow Size and Asymmetry of Sagittarius A*: Limitations from Interstellar Scattering","license":"http://arxiv.org/licenses/nonexclusive-distrib/1.0/","headline":"","cross_cats":["astro-ph.GA"],"primary_cat":"astro-ph.IM","authors_text":"Michael D. Johnson, Ramesh Narayan, Ziyan Zhu","submitted_at":"2018-11-05T23:07:33Z","abstract_excerpt":"The Event Horizon Telescope (EHT), a global 230 GHz VLBI array, achieves an angular resolution of ${\\approx} 20\\,\\mu{\\rm as}$, sufficient to resolve the supermassive black hole Sagittarius A* (Sgr A*). This resolution may soon enable measurement of the black hole \"shadow\" size and asymmetry, predicted to be ${\\approx}50\\,\\mu$as and ${\\lesssim} 3\\,\\mu$as, respectively. Measurements that depart from these values could indicate a violation of the \"no-hair theorem.\" However, refractive scattering by the turbulent ionized interstellar medium distorts the image of Sgr A*, affecting its apparent size"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"1811.02079","kind":"arxiv","version":1},"verdict":{"id":null,"model_set":{},"created_at":null,"strongest_claim":"","one_line_summary":"","pipeline_version":null,"weakest_assumption":"","pith_extraction_headline":""},"references":{"count":0,"sample":[],"resolved_work":0,"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57","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"}