What you see is what you get: Empirically measured bolometric luminosities of Little Red Dots

article What you see is what you get: Empirically measured bolometric luminosities of Little Red Dots published yes Jenny E. Greene author David J. Setton author Lukas J. Furtak author Rohan P. Naidu author Marta Volonteri author Pratika Dayal author Ivo Labbe author Pieter Van Dokkum author Rachel Bezanson author Gabriel Brammer author Sam E. Cutler author Karl Glazebrook author Anna De Graaff author Michaela Hirschmann author Raphael E. Hviding author Vasily Kokorev author Joel Leja author Hanpu Liu author Yilun Ma author Jorryt J Matthee author 7439a258-f3c0-11ec-9501-9df22fe067200000-0003-2871-127X Themiya Nanayakkara author Pascal A. Oesch author Richard Pan author Sedona H. Price author Justin S. Spilker author Bingjie Wang author John R. Weaver author Katherine E. Whitaker author Christina C. Williams author Adi Zitrin author JoMa department Young galaxies as tracers and agents of cosmic reionization project New populations of red active galactic nuclei (known as “little red dots”) discovered by JWST exhibit remarkable spectral energy distributions. Leveraging X-ray through far-infrared observations of two of the most luminous known little red dots, we directly measure their bolometric luminosities. We find evidence that more than half of the bolometric luminosity likely emerges in the rest-frame optical, with Lbol/L5100 = 5, roughly half the value for “standard” active galactic nuclei. Meanwhile, the X-ray emitting corona, UV-emitting blackbody, and reprocessed mid to far-infrared emission are all considerably subdominant, assuming that the far-infrared luminosity is well below current measured limits. We present new bolometric corrections that dramatically lower inferred bolometric luminosities by a factor of 10 compared to published values in the literature. These bolometric corrections are in accord with expectations from models in which gas absorption and reprocessing are responsible for the red rest-frame optical colors of little red dots. We discuss how this lowered luminosity scale suggests a lower mass scale for the population by at least an order of magnitude (e.g., ∼105–107 M⊙ black holes, and ∼108 M⊙ galaxies), alleviating tensions with clustering, overmassive black holes, and the integrated black hole mass density in the Universe. https://research-explorer.ista.ac.at/download/21715/21792/2026_AstrophysicalJour_Greene.pdf application/pdfno IOP Publishing2026 eng The Astrophysical Journal 0004-637X 1538-4357 2509.0543410.3847/1538-4357/ae1836 9962 J. E. Greene et al., “What you see is what you get: Empirically measured bolometric luminosities of Little Red Dots,” The Astrophysical Journal, vol. 996, no. 2. IOP Publishing, 2026. Greene, J. E., Setton, D. J., Furtak, L. J., Naidu, R. P., Volonteri, M., Dayal, P., … Zitrin, A. (2026). What you see is what you get: Empirically measured bolometric luminosities of Little Red Dots. The Astrophysical Journal. IOP Publishing. <a href="https://doi.org/10.3847/1538-4357/ae1836">https://doi.org/10.3847/1538-4357/ae1836</a> Greene JE, Setton DJ, Furtak LJ, et al. What you see is what you get: Empirically measured bolometric luminosities of Little Red Dots. The Astrophysical Journal. 2026;996(2). doi:<a href="https://doi.org/10.3847/1538-4357/ae1836">10.3847/1538-4357/ae1836</a> Greene, Jenny E., David J. Setton, Lukas J. Furtak, Rohan P. Naidu, Marta Volonteri, Pratika Dayal, Ivo Labbe, et al. “What You See Is What You Get: Empirically Measured Bolometric Luminosities of Little Red Dots.” The Astrophysical Journal. IOP Publishing, 2026. <a href="https://doi.org/10.3847/1538-4357/ae1836">https://doi.org/10.3847/1538-4357/ae1836</a>. Greene JE, Setton DJ, Furtak LJ, Naidu RP, Volonteri M, Dayal P, Labbe I, Van Dokkum P, Bezanson R, Brammer G, Cutler SE, Glazebrook K, De Graaff A, Hirschmann M, Hviding RE, Kokorev V, Leja J, Liu H, Ma Y, Matthee JJ, Nanayakkara T, Oesch PA, Pan R, Price SH, Spilker JS, Wang B, Weaver JR, Whitaker KE, Williams CC, Zitrin A. 2026. What you see is what you get: Empirically measured bolometric luminosities of Little Red Dots. The Astrophysical Journal. 996(2), 129. J.E. Greene, D.J. Setton, L.J. Furtak, R.P. Naidu, M. Volonteri, P. Dayal, I. Labbe, P. Van Dokkum, R. Bezanson, G. Brammer, S.E. Cutler, K. Glazebrook, A. De Graaff, M. Hirschmann, R.E. Hviding, V. Kokorev, J. Leja, H. Liu, Y. Ma, J.J. Matthee, T. Nanayakkara, P.A. Oesch, R. Pan, S.H. Price, J.S. Spilker, B. Wang, J.R. Weaver, K.E. Whitaker, C.C. Williams, A. Zitrin, The Astrophysical Journal 996 (2026). Greene, Jenny E., et al. “What You See Is What You Get: Empirically Measured Bolometric Luminosities of Little Red Dots.” The Astrophysical Journal, vol. 996, no. 2, 129, IOP Publishing, 2026, doi:<a href="https://doi.org/10.3847/1538-4357/ae1836">10.3847/1538-4357/ae1836</a>. 217152026-04-12T22:01:50Z2026-05-04T11:20:42Z