{"work":{"id":"f4cab114-be94-47c0-ad7d-c869a0305160","openalex_id":"https://openalex.org/W7151256024","doi":"10.48550/arxiv.2604.03370","arxiv_id":"2604.03370","raw_key":null,"title":"Holes in the BH$^\\star$? AGN signatures in the FUV spectrum of a black-hole dominated Little Red Dot at $z=7.04$","authors":null,"authors_text":"Xihan Ji, Gabriele Pezzulli, Francesco D'Eugenio, Roberto Maiolino, Stefano Carniani, Sandro Tacchella, Gareth Jones, Aaron Smith, Joris Witstok, Andrew C. Fabian","year":2026,"venue":"astro-ph.GA","abstract":"It has been suggested that \"Little Red Dots\" (LRDs) might be accreting black holes enshrouded by dense gas in a nearly closed geometry, which completely covers the central black hole, leading to an atmosphere-like structure known as the \"black-hole star\" ($\\rm BH^\\star$). We test this scenario by analysing new JWST spectroscopy in the far ultraviolet (FUV, rest-frame) of the prototypical LRD Abell2744-QSO1, at $z=7.04$. We found the presence of broad Ly$\\alpha$ emission with an FWHM of $\\sim 1000$ km/s, and detections of OI, CIV, and/or FeII emission lines. The NIRCam imaging and NIRSpec slit images indicate that the low-velocity component ($v\\lesssim 200$ km/s) of Ly$\\alpha$ is likely spatially extended, but the high-velocity component ($v\\gtrsim 200$ km/s) of Ly$\\alpha$ remains unresolved. Based on the multi-component kinematics and flux of Ly$\\alpha$ relative to Balmer lines, we conclude that the observed line profile is unlikely to be broadened by subsequent resonant scattering through the interstellar medium. This suggests that the high-velocity component of Ly$\\alpha$ originates in the broad-line region, although resonant scattering in the dense gas likely makes Ly$\\alpha$ broader than H$\\alpha$ as observed. The nebular features of this LRD indicate that there is at least one relatively optically thin direction where Ly$\\alpha$ can escape from the broad-line region (BLR). We also found indications that photons from the BLR are powering fluorescence of FeII and OI on a larger physical scale. The FUV features thus challenge the fully-covered geometry interpretation and suggest that there are \"holes\" in the $\\rm BH^\\star$, or the absorbing medium is simply clumpy.","external_url":"https://arxiv.org/abs/2604.03370","cited_by_count":0,"metadata_source":"pith","metadata_fetched_at":"2026-08-05T02:28:24.338817+00:00","pith_arxiv_id":"2604.03370","created_at":"2026-05-10T11:10:09.255543+00:00","updated_at":"2026-08-05T02:49:54.815029+00:00","title_quality_ok":true,"display_title":"Holes in the BH$^\\star$? AGN signatures in the FUV spectrum of a black-hole dominated Little Red Dot at $z=7.04$","render_title":"Holes in the BH$^\\star$? AGN signatures in the FUV spectrum of a black-hole dominated Little Red Dot at $z=7.04$"},"hub":{"state":{"work_id":"f4cab114-be94-47c0-ad7d-c869a0305160","tier":"hub","tier_reason":"10+ Pith inbound or 1,000+ external citations","pith_inbound_count":16,"external_cited_by_count":0,"distinct_field_count":2,"first_pith_cited_at":"2026-04-16T02:04:33+00:00","last_pith_cited_at":"2026-06-29T18:00:00+00:00","author_build_status":"not_needed","summary_status":"needed","contexts_status":"needed","graph_status":"needed","ask_index_status":"not_needed","reader_status":"not_needed","recognition_status":"not_needed","updated_at":"2026-08-23T20:39:48.433999+00:00","tier_text":"hub"},"tier":"hub","role_counts":[{"context_role":"background","n":1}],"polarity_counts":[{"context_polarity":"background","n":1}],"runs":{},"summary":{},"graph":{},"authors":[]}}