VizieR Online Data Catalog: Carbon-loud SDSS BOSS type II quasars at z>2 (Silva+, 2020)

The objects studied in this paper are a subsample of quasars from the spectroscopic quasar sample of the BOSS of the SDSS Data Release 9 (see Gunn et al. 2006AJ....131.2332G; Alexandroff et al. 2013MNRAS.435.3306A, Cat. J/MNRAS/435/3306 and references therein). Alexandroff et al. (2013MNRAS.435.3306A, Cat. J/MNRAS/435/3306) selected 452 candidate QSO2s in the redshift range 2.0<z<4.3, using selection criteria that included 5σ detections in both Lyα and CIV, with both lines also requiring to have full width at half-maximum (FWHM)<2000km/s. In this study, we consider only the 145 type II Class A quasar candidates of Alexandroff et al. (2013MNRAS.435.3306A, Cat. J/MNRAS/435/3306), in order to avoid unnecessary contamination from unobscured objects.

In addition, we make use of rest-frame optical line fluxes of QSO2 candidates published by Greene et al. (2014ApJ...788...91G), who used Triplespec on the Apache Point Observatory 3.5-m Telescope (APO), Folded-port Infrared Echellete (FIRE) on the 6.5-m Baade-Magellan Telescope, and the Gemini Near-Infrared Spectrograph (GNIRS) on the Gemini North 8.1-m Telescope. The sample of Greene et al. (2014ApJ...788...91G) consists of 19 candidate QSO2s at 2.0<z<3.4; here we use the line fluxes of 16 candidate QSO2s which are also present in the Class A subsample discussed above.

As a comparison sample, we used emission-line fluxes of HzRGs at 2.27=<z=<3.56 from the literature (see Table A1). The objects were observed using the Low Resolution Imaging Spectrometer (LRIS) in spectropolarimetry mode at the Keck II 10-m telescope, the Infrared Spectrometer and Array Camera (ISAAC) in long-slit mode, and Focal Reducer and Spectrograph (FORS1) at the Very Large Telescope (VLT), OH Airglow Suppressor (OHS) spectrograph mounted on the Subaru telescope, and ESO Multi-Mode Instrument (EMMI) at the New Technology Telescope (NTT).

We also include four 'core extremely red quasars' (core-ERQs; see Ross et al. 2015MNRAS.453.3932R, Zakamska et al. 2016MNRAS.459.3144Z, Hamann et al. 2017MNRAS.464.3431H, Cat. J/MNRAS/464/3431, Villar Martin et al. 2020A&A...634A.116V) in the redshift range 2.3<z<2.6.

(3 data files).