{"publication_status":"published","OA_type":"gold","tmp":{"name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)","image":"/images/cc_by.png","short":"CC BY (4.0)","legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode"},"oa_version":"Published Version","_id":"22960","title":"Little red dots host black hole stars: A unified family of gas-reddened AGN revealed by JWST/NIRSpec spectroscopy","fulldoi":"https://doi.org/10.1093/mnras/stag1567","article_number":"stag1567","file_date_updated":"2026-10-01T11:25:20Z","citation":{"ama":"de Graaff A, Hviding RE, Naidu RP, et al. Little red dots host black hole stars: A unified family of gas-reddened AGN revealed by JWST/NIRSpec spectroscopy. <i>Monthly Notices of the Royal Astronomical Society</i>. 2026;551(3). doi:<a href=\"https://doi.org/10.1093/mnras/stag1567\">10.1093/mnras/stag1567</a>","chicago":"de Graaff, Anna, Raphael E Hviding, Rohan P Naidu, Jenny E Greene, Tim B Miller, Joel Leja, Jorryt J Matthee, et al. “Little Red Dots Host Black Hole Stars: A Unified Family of Gas-Reddened AGN Revealed by JWST/NIRSpec Spectroscopy.” <i>Monthly Notices of the Royal Astronomical Society</i>. Oxford University Press, 2026. <a href=\"https://doi.org/10.1093/mnras/stag1567\">https://doi.org/10.1093/mnras/stag1567</a>.","ista":"de Graaff A, Hviding RE, Naidu RP, Greene JE, Miller TB, Leja J, Matthee JJ, Brammer G, Katz H, Bezanson R, Boogaard LA, Bose S, Chisholm J, Cleri NJ, Dayal P, Feldmann R, Fudamoto Y, Fujimoto S, Furtak LJ, Glazebrook K, Gottumukkala R, Heintz KE, Kokorev V, Labbe I, Maseda MV, McConachie I, Nanayakkara T, Nelson E, Nowaczyk P, Oesch PA, Rix H-W, Setton DJ, Torralba Torregrosa A, Walter F, Wang B, Weibel A, van der Wel A. 2026. Little red dots host black hole stars: A unified family of gas-reddened AGN revealed by JWST/NIRSpec spectroscopy. Monthly Notices of the Royal Astronomical Society. 551(3), stag1567.","short":"A. de Graaff, R.E. Hviding, R.P. Naidu, J.E. Greene, T.B. Miller, J. Leja, J.J. Matthee, G. Brammer, H. Katz, R. Bezanson, L.A. Boogaard, S. Bose, J. Chisholm, N.J. Cleri, P. Dayal, R. Feldmann, Y. Fudamoto, S. Fujimoto, L.J. Furtak, K. Glazebrook, R. Gottumukkala, K.E. Heintz, V. Kokorev, I. Labbe, M.V. Maseda, I. McConachie, T. Nanayakkara, E. Nelson, P. Nowaczyk, P.A. Oesch, H.-W. Rix, D.J. Setton, A. Torralba Torregrosa, F. Walter, B. Wang, A. Weibel, A. van der Wel, Monthly Notices of the Royal Astronomical Society 551 (2026).","mla":"de Graaff, Anna, et al. “Little Red Dots Host Black Hole Stars: A Unified Family of Gas-Reddened AGN Revealed by JWST/NIRSpec Spectroscopy.” <i>Monthly Notices of the Royal Astronomical Society</i>, vol. 551, no. 3, stag1567, Oxford University Press, 2026, doi:<a href=\"https://doi.org/10.1093/mnras/stag1567\">10.1093/mnras/stag1567</a>.","apa":"de Graaff, A., Hviding, R. E., Naidu, R. P., Greene, J. E., Miller, T. B., Leja, J., … van der Wel, A. (2026). Little red dots host black hole stars: A unified family of gas-reddened AGN revealed by JWST/NIRSpec spectroscopy. <i>Monthly Notices of the Royal Astronomical Society</i>. Oxford University Press. <a href=\"https://doi.org/10.1093/mnras/stag1567\">https://doi.org/10.1093/mnras/stag1567</a>","ieee":"A. de Graaff <i>et al.</i>, “Little red dots host black hole stars: A unified family of gas-reddened AGN revealed by JWST/NIRSpec spectroscopy,” <i>Monthly Notices of the Royal Astronomical Society</i>, vol. 551, no. 3. Oxford University Press, 2026."},"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","day":"01","issue":"3","month":"09","file":[{"file_id":"23026","creator":"dernst","success":1,"file_size":14983705,"checksum":"a82b93954671a12bb60d8d7a4a4d526b","content_type":"application/pdf","relation":"main_file","date_updated":"2026-10-01T11:25:20Z","access_level":"open_access","file_name":"2026_MonthNoticesRAS_deGraaff.pdf","date_created":"2026-10-01T11:25:20Z"}],"supplementarymaterial":"yes","das_tickbox":"1","status":"public","date_created":"2026-09-17T11:06:40Z","publication_identifier":{"issn":["0035-8711"],"eissn":["1365-2966"]},"language":[{"iso":"eng"}],"doi":"10.1093/mnras/stag1567","article_type":"original","researchdata_availability":"yes","oa":1,"external_id":{"arxiv":["2511.21820"]},"date_updated":"2026-10-01T11:31:16Z","dataavailabilitystatement":"All data used in this work are publicly available through the\r\nDAWN JWST Archive (https://dawn-cph.github.io/dja/index.h\r\ntml). The spectra used in this work are part of version 4.5 of the\r\nDJA (G. Brammer & F. Valentino 2025). We also release our complete LRD catalogue, together with all key measurements made All data used in this work are publicly available through the\r\nDAWN JWST Archive (https://dawn-cph.github.io/dja/index.h\r\ntml). The spectra used in this work are part of version 4.5 of the\r\nDJA (G. Brammer & F. Valentino 2025). We also release our complete LRD catalogue, together with all key measurements made in the modified blackbody fitting and emission-line fitting. The\r\ntable can be found at https://doi.org/10.5281/zenodo.21977747,\r\nand its contents are described in Appendix B.\r\n\r\n","author":[{"full_name":"de Graaff, Anna","first_name":"Anna","last_name":"de Graaff"},{"last_name":"Hviding","first_name":"Raphael E","full_name":"Hviding, Raphael E"},{"first_name":"Rohan P","full_name":"Naidu, Rohan P","last_name":"Naidu"},{"last_name":"Greene","first_name":"Jenny E","full_name":"Greene, Jenny E"},{"first_name":"Tim B","full_name":"Miller, Tim B","last_name":"Miller"},{"first_name":"Joel","full_name":"Leja, Joel","last_name":"Leja"},{"full_name":"Matthee, Jorryt J","first_name":"Jorryt J","orcid":"0000-0003-2871-127X","last_name":"Matthee","id":"7439a258-f3c0-11ec-9501-9df22fe06720"},{"last_name":"Brammer","full_name":"Brammer, Gabriel","first_name":"Gabriel"},{"first_name":"Harley","full_name":"Katz, Harley","last_name":"Katz"},{"first_name":"Rachel","full_name":"Bezanson, Rachel","last_name":"Bezanson"},{"first_name":"Leindert A","full_name":"Boogaard, Leindert A","last_name":"Boogaard"},{"full_name":"Bose, Sownak","first_name":"Sownak","last_name":"Bose"},{"last_name":"Chisholm","first_name":"John","full_name":"Chisholm, John"},{"first_name":"Nikko J","full_name":"Cleri, Nikko J","last_name":"Cleri"},{"first_name":"Pratika","full_name":"Dayal, Pratika","last_name":"Dayal"},{"first_name":"Robert","full_name":"Feldmann, Robert","last_name":"Feldmann"},{"full_name":"Fudamoto, Yoshinobu","first_name":"Yoshinobu","last_name":"Fudamoto"},{"last_name":"Fujimoto","full_name":"Fujimoto, Seiji","first_name":"Seiji"},{"full_name":"Furtak, Lukas J","first_name":"Lukas J","last_name":"Furtak"},{"last_name":"Glazebrook","first_name":"Karl","full_name":"Glazebrook, Karl"},{"first_name":"Rashmi","full_name":"Gottumukkala, Rashmi","last_name":"Gottumukkala"},{"first_name":"Kasper E","full_name":"Heintz, Kasper E","last_name":"Heintz"},{"last_name":"Kokorev","first_name":"Vasily","full_name":"Kokorev, Vasily"},{"full_name":"Labbe, Ivo","first_name":"Ivo","last_name":"Labbe"},{"full_name":"Maseda, Michael V","first_name":"Michael V","last_name":"Maseda"},{"last_name":"McConachie","first_name":"Ian","full_name":"McConachie, Ian"},{"full_name":"Nanayakkara, Themiya","first_name":"Themiya","last_name":"Nanayakkara"},{"last_name":"Nelson","first_name":"Erica","full_name":"Nelson, Erica"},{"first_name":"Przemysław","full_name":"Nowaczyk, Przemysław","last_name":"Nowaczyk"},{"last_name":"Oesch","full_name":"Oesch, Pascal A","first_name":"Pascal A"},{"first_name":"Hans-Walter","full_name":"Rix, Hans-Walter","last_name":"Rix"},{"last_name":"Setton","first_name":"David J","full_name":"Setton, David J"},{"id":"018f0249-0e87-11f0-b167-cbce08fbd541","last_name":"Torralba Torregrosa","orcid":"0000-0001-5586-6950","full_name":"Torralba Torregrosa, Alberto","first_name":"Alberto"},{"last_name":"Walter","first_name":"Fabian","full_name":"Walter, Fabian"},{"last_name":"Wang","first_name":"Bingjie","full_name":"Wang, Bingjie"},{"first_name":"Andrea","full_name":"Weibel, Andrea","last_name":"Weibel"},{"last_name":"van der Wel","first_name":"Arjen","full_name":"van der Wel, Arjen"}],"year":"2026","scopus_import":"1","type":"journal_article","volume":551,"department":[{"_id":"JoMa"}],"arxiv":1,"article_processing_charge":"Yes","acknowledgement":"AdG thanks Devesh Nandal for discussions on the properties\r\nof convective envelopes and Hayashi limit, and the students of\r\nthe I-HOW JWST Workshop (Barbora Adamcova, Biswaraj Palit,\r\nOlena Pastoven, and Weronika Puchalska) for their help in producing an early version of Figs 8 and 10. This work is based on\r\nobservations made with the NASA/ESA/CSA James Webb Space\r\nTelescope. The data were obtained from the Mikulski Archive for\r\nSpace Telescopes at the Space Telescope Science Institute, which\r\nis operated by the Association of Universities for Research in\r\nAstronomy, Inc., under NASA contract NAS 5-03127 for JWST.\r\nThese observations are associated with programs 1180, 1181,\r\n1208, 1212, 1213, 1215, 1286, 1345, 1433, 2198, 2561, 2750, 2767,\r\n4106, 4233, 5105, 5224, 6368, and 6585. Support for program no.\r\n4233 was provided by NASA through a grant from the Space\r\nTelescope Science Institute, which is operated by the Association\r\nof Universities for Research in Astronomy, Inc., under NASA\r\ncontract NAS 5-03127.\r\nAdG acknowledges support from a Clay Fellowship awarded by\r\nthe Smithsonian Astrophysical Observatory. REH acknowledges\r\nsupport by the German Aerospace Center (DLR) and the Federal\r\nMinistry for Economic Affairs and Energy (BMWi) through program 50OR2403 ‘RUBIES’. The Cosmic Dawn Centerisfunded by\r\nthe Danish National Research Foundation (DNRF) under grant\r\nno. 140. This work has received funding from the Swiss State\r\nSecretariat for Education, Research and Innovation (SERI) under\r\ncontract no. MB22.00072, as well as from the Swiss National Science Foundation (SNSF) through project grant 200020_207349.\r\nTBM was supported by a CIERA fellowship. PD warmly acknowledges support from an NSERC discovery grant (RGPIN-2025-\r\n06182). KG acknowledges support from Australian Research\r\nCouncil Laureate Fellowship FL180100060. LAB acknowledges\r\nsupport from the Dutch Research Council (NWO) under grant\r\nVI.Veni.242.055 (https://doi.org/10.61686/LAJVP77714) and the\r\nERC Consolidator grant 101088676 (‘VOYAJ’). YF is supported by\r\nJSPS KAKENHI grant nos JP22K21349 and JP23K13149.","PlanS_conform":"1","quality_controlled":"1","ddc":["520"],"has_accepted_license":"1","publication":"Monthly Notices of the Royal Astronomical Society","OA_place":"publisher","date_published":"2026-09-01T00:00:00Z","intvolume":"       551","publisher":"Oxford University Press","abstract":[{"lang":"eng","text":"We construct and characterize a sample of 146 little red dots (LRDs) across 2.0<z<9.3, selecting all sources with v-shaped\r\nultraviolet (UV)–optical continua from James Webb Space Telescope (JWST) NIRSpec/PRISM spectra and compact morphologies in NIRCam/F444W imaging. We show that LRD continuum spectra are well described by modified blackbodies\r\nacross ∼ 0.4 − 1.0 µm, with typical T ∼ 5000 K (λpeak ∼ 0.65 µm) across 2 dex in luminosity, and a tail toward T ∼ 2000 K.\r\nLRDs therefore trace a locus in the Hertzsprung–Russell diagram that is analogous to stars on the Hayashi track, strongly\r\nsupporting the picture that LRDs are active galactic nucleus (AGN) embedded in optically thick dense gas envelopes.\r\nHotter LRDs with λpeak < 0.65 µm typically have strong Balmer breaks, redder UV slopes, and high optical luminosities;\r\nother LRDs show weak or no Balmer breaks, and wide variety in βUV and L5100. Crucially, we demonstrate that the UV–\r\noptical continua are strongly linked to the Hα, Hβ, [O iii], and O i line properties. There is a tight linear relation between\r\nthe Hα and optical continuum luminosities, as well as Hα and O i λ8446, indicating that Balmer, O i, and optical emission\r\nmust primarily be powered by the same source. The Balmer decrement increases strongly toward higher LHα, L5100, and\r\nBalmer break strength, providing key evidence for luminosity-dependent effects of collisional (de-)excitation and resonant\r\nscattering in the gaseous envelopes. In contrast, we show that [O iii] emission likely originates from star-forming host\r\ngalaxies, with strong variation in the AGN-to-host ratio among the LRD population. Our work presents an empirical\r\ndescription of the nature and structure of LRDs, defining a new benchmark for ongoing LRD model developments."}],"DOAJ_listed":"1"}