Exploring the Spectral Energy Distributions of Luminous Broad Absorption Line Quasars at High Redshift

Abstract We present the multiwavelength spectral energy distributions (SEDs) for 65 luminous broad absorption line (BAL) quasars with redshifts 1.55 ≲ z ≲ 3.50 from the Gemini Near Infrared Spectrograph–Distant Quasar Survey (GNIRS-DQS). We integrate data from a variety of ground- and space-based observatories to construct a comprehensive spectral profile of these objects from radio through X-rays. In addition, we present a mid-infrared to X-ray composite SED of these sources. Our data set represents the most uniform sample of BAL quasars, providing a statistically robust set of SEDs. Our findings indicate that the BAL quasars in the GNIRS-DQS sample exhibit significant reddening in the ultraviolet-optical continuum relative to their non-BAL counterparts, consistent with previous studies. Notably, our analysis reveals no significant differences in the mid- or near-infrared spectral regime between BAL and non-BAL quasars. In line with previous work, we find no strong evidence that BAL and non-BAL quasars possess fundamentally different SEDs, also consistent with recent findings that both groups display similar rest-frame optical emission-line properties.