UV-luminous, star-forming hosts of z ~ 2 reddened quasars in the Dark Energy Survey

Journal Article · Fri Jan 05 00:00:00 EST 2018 · Monthly Notices of the Royal Astronomical Society

DOI:https://doi.org/10.1093/mnras/stx3332· OSTI ID:1423223

Wethers, C. F.; Banerji, M.; Hewett, P. C.; Lemon, C. A.; McMahon, R. G.; Reed, S. L.; Shen, Y.; Abdalla, F. B.; Benoit-Lévy, A.; Brooks, D.; Buckley-Geer, E.; Capozzi, D.; Carnero Rosell, A.; CarrascoKind, M.; Carretero, J.; Cunha, C. E.; D'Andrea, C. B.; da Costa, L. N.; DePoy, D. L.; Desai, S. ; Doel, P.; Flaugher, B.; Fosalba, P.; Frieman, J.; García-Bellido, J.; Gerdes, D. W.; Gruen, D.; Gruendl, R. A.; Gschwend, J.; Gutierrez, G.; Honscheid, K.; James, D. J.; Jeltema, T.; Kuehn, K.; Kuhlmann, S.; Kuropatkin, N.; Lima, M.; Maia, M. A. G.; Marshall, J. L.; Martini, P.; Menanteau, F.; Miquel, R.; Nichol, R. C.; Nord, B.; Plazas, A. A.; Romer, A. K.; Sanchez, E.; Scarpine, V.; Schindler, R.; Schubnell, M.; Sevilla-Noarbe, I.; Smith, M.; Smith, R. C.; Soares-Santos, M.; Sobreira, F.; Suchyta, E.; Tarle, G.; Walker, A. R.

We present the first rest-frame UV population study of 17 heavily reddened, high-luminosity (E(B-V)$$_{\rm{QSO}}\gtrsim$$ 0.5; L$$_{\rm{bol}}>$$ 10$$^{46}$$ergs$$^{-1}$$) broad-line quasars at $1.5 < z < 2.7$. We combine the first year of deep, optical, ground-based observations from the Dark Energy Survey (DES) with the near infrared VISTA Hemisphere Survey (VHS) and UKIDSS Large Area Survey (ULAS) data, from which the reddened quasars were initially identified. We demonstrate that the significant dust reddening towards the quasar in our sample allows host galaxy emission to be detected at the rest-frame UV wavelengths probed by the DES photometry. By exploiting this reddening effect, we disentangle the quasar emission from that of the host galaxy via spectral energy distribution (SED) fitting. We find evidence for a relatively unobscured, star-forming host galaxy in at least ten quasars, with a further three quasars exhibiting emission consistent with either star formation or scattered light. From the rest-frame UV emission, we derive instantaneous, dust-corrected star formation rates (SFRs) in the range 25 < SFR$$_{\rm{UV}}$$ < 365 M$$_{\odot}$$yr$$^{-1}$$, with an average SFR$$_{\rm{UV}}$$ = 130 $$\pm$$ 95 M$$_{\odot}$$yr$$^{-1}$$. In conclusion, we find a broad correlation between SFR$$_{\rm{UV}}$$ and the bolometric quasar luminosity. Overall, our results show evidence for coeval star formation and black hole accretion occurring in luminous, reddened quasars at the peak epoch of galaxy formation.

• Research Organization: SLAC National Accelerator Laboratory (SLAC), Menlo Park, CA (United States); Fermi National Accelerator Laboratory (FNAL), Batavia, IL (United States); Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: USDOE Office of Science (SC), High Energy Physics (HEP); USDOE Office of Science (SC), Advanced Scientific Computing Research (ASCR)
• Contributing Organization: DES Collaboration
• Grant/Contract Number: AC02-07CH11359; AC05-00OR22725
• OSTI ID: 1423223
• Alternate ID(s): OSTI ID: 1426563
• Report Number(s): arXiv:1801.02635; FERMILAB-PUB-18-022-A-AD-AE-CD; 1647255; TRN: US1801721
• Journal Information: Monthly Notices of the Royal Astronomical Society, Vol. 475, Issue 3; ISSN 0035-8711
• Publisher: Royal Astronomical Society
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
galaxies: active
galaxies: evolution
galaxies: high-redshift
quasars: general
galaxies: star formation
ultraviolet: galaxies