{"paper":{"title":"ATLAS. III. Dust Around Little Red Dots: Hydrogen Line Ratios beyond Dust-free Non-Case B Models","license":"http://creativecommons.org/licenses/by/4.0/","headline":"","cross_cats":[],"primary_cat":"astro-ph.GA","authors_text":"Hiroto Yanagisawa, Makoto Ando, Masami Ouchi, Minami Nakane, Tomokazu Kiyota, Yoshiaki Ono, Yuichi Harikane, Yui Takeda, Yurina Nakazato, Yuta Kageura","submitted_at":"2026-08-11T11:59:38Z","abstract_excerpt":"We investigate broad hydrogen line ratios in little red dots (LRDs) using five high-redshift ($z>2$) sources from JWST/NIRSpec medium/high-resolution spectra in the DAWN JWST Archive and fifteen low-redshift sources ($z=0.1$--$0.9$) from the literature, all with broad H$\\beta$ detected at $>5\\sigma$. After carefully measuring the broad-line fluxes while accounting for absorption features and neighboring emission lines, we find that the broad H$\\alpha$/H$\\beta$ ratios are very high, ranging from 6 to 30, well above the Case B recombination value. Using plane-parallel \\textsc{Cloudy} photoioniza"},"claims":{"count":0,"items":[],"snapshot_sha256":"258153158e38e3291e3d48162225fcdb2d5a3ed65a07baac614ab91432fd4f57"},"source":{"id":"2608.10832","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":""},"integrity":{"clean":true,"summary":{"advisory":0,"critical":0,"by_detector":{},"informational":0},"endpoint":"/pith/2608.10832/integrity.json","findings":[],"available":true,"detectors_run":[],"snapshot_sha256":"c28c3603d3b5d939e8dc4c7e95fa8dfce3d595e45f758748cecf8e644a296938"},"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"}