Extremely Red Quasars in BOSS

Autor: Rachael M. Alexandroff, Nicholas P. Ross, Nadia L. Zakamska, Kelly D. Denney, Ben Cook, Jenny E. Greene, Donald P. Schneider, Fred Hamann, H. Herbst, W. Niel Brandt, Isabelle Paris, Gordon T. Richards, Carolin Villforth, Michael A. Strauss
Přispěvatelé: Laboratoire d'Astrophysique de Marseille (LAM), Centre National de la Recherche Scientifique (CNRS)-Institut national des sciences de l'Univers (INSU - CNRS)-Aix Marseille Université (AMU)-Centre National d'Études Spatiales [Toulouse] (CNES), Aix Marseille Université (AMU)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales [Toulouse] (CNES)-Centre National de la Recherche Scientifique (CNRS)
Rok vydání: 2016
Předmět:
Zdroj: Monthly Notices of the Royal Astronomical Society
Monthly Notices of the Royal Astronomical Society, Oxford University Press (OUP): Policy P-Oxford Open Option A, 2017, 000 (3), pp.1-32. ⟨10.1093/mnras/stw2387⟩
Hamann, F, Zakamska, N L, Ross, N, Paris, I, Alexandroff, R M, Villforth, C, Richards, G T, Herbst, H, Brandt, W N, Cook, B, Denney, K D, Greene, J E, Schneider, D P & Strauss, M A 2016, ' Extremely red quasars in BOSS ', Monthly Notices of the Royal Astronomical Society, vol. 464, no. 3, pp. 3431-3463 . https://doi.org/10.1093/mnras/stw2387
Monthly Notices of the Royal Astronomical Society, 2017, 000 (3), pp.1-32. ⟨10.1093/mnras/stw2387⟩
ISSN: 0035-8711
1365-2966
DOI: 10.48550/arxiv.1609.07241
Popis: Red quasars are candidate young objects in an early transition stage of massive galaxy evolution. Our team recently discovered a population of extremely red quasars (ERQs) in the Baryon Oscillation Spectroscopic Survey (BOSS) that has a suite of peculiar emission-line properties including large rest equivalent widths (REWs), unusual "wingless" line profiles, large NV/Lya, NV/CIV, SiIV/CIV and other flux ratios, and very broad and blueshifted [OIII] 5007. Here we present a new catalog of CIV and NV emission-line data for 216,188 BOSS quasars to characterize the ERQ line properties further. We show that they depend sharply on UV-to-mid-IR color, secondarily on REW(CIV), and not at all on luminosity or the Baldwin Effect. We identify a "core" sample of 97 ERQs with nearly uniform peculiar properties selected via i-W3 > 4.6 (AB) and REW(CIV) > 100 A at redshifts 2.0-3.4. A broader search finds 235 more red quasars with similar unusual characteristics. The core ERQs have median luminosity log L (ergs/s) ~ 47.1, sky density 0.010 deg^-2, surprisingly flat/blue UV spectra given their red UV-to-mid-IR colors, and common outflow signatures including BALs or BAL-like features and large CIV emission-line blueshifts. Their SEDs and line properties are inconsistent with normal quasars behind a dust reddening screen. We argue that the core ERQs are a unique obscured quasar population with extreme physical conditions related to powerful outflows across the line-forming regions. Patchy obscuration by small dusty clouds could produce the observed UV extinctions without substantial UV reddening.
36 pages, 18 figures, accepted for publication in the MNRAS. The emission-line catalog described in this paper, along with supplemental tables and figures, can be downloaded from the University of California Digital Libraries at the URL https://dx.doi.org/10.6086/D1H59V (digital object identifier DOI:10.6086/D1H59V)
Databáze: OpenAIRE
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