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Abstract We present the optical–near-infrared spectral energy distributions (SED) and near-infrared variability properties of 30 low-redshift iron low-ionization Broad Absorption Line quasars (FeLoBALQs) and matched samples of LoBALQs and unabsorbed quasars. Significant correlations between the SED properties and accretion rate indicators found among the unabsorbed comparison sample objects suggest an intrinsic origin for SED differences. A range of reddening likely mutes these correlations among the FeLoBAL quasars. The rest-frame optical-band reddening is correlated with the location of the outflow, suggesting a link between the outflows and the presence of dust. We analyzed the WISE variability and provide a correction for photometry uncertainties in an appendix. We found an anticorrelation between the variability amplitude and inferred continuum emission region size, and we suggest that as the origin of the anticorrelation between variability amplitude and luminosity typically observed in quasars. We found that the LoBALQ Optical Emission-line and other parameters are more similar to those of the unabsorbed continuum sample objects than the FeLoBALQs. Thus, FeLoBAL quasars are a special population of objects. We interpret the results using an accretion-rate scenario for FeLoBAL quasars. The high-accretion-rate FeLoBAL quasars are radiating powerfully enough to drive a thick, high-velocity outflow. Quasars with intermediate accretion rates may have an outflow, but it is not sufficiently thick to include Feiiabsorption. Low-accretion-rate FeLoBAL outflows originate in absorption in a failing torus, no longer optically thick enough to reprocess radiation into the near-IR.
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Unveiling the infrared excess of SIPS J2045–6332: evidence for a young stellar object with potential low-mass companion
ABSTRACT The Disc Detective project, a citizen science initiative, aims to identify circumstellar discs around stars by detecting objects with infrared (IR) excess using data from the Wide-field Infrared Survey Explorer (WISE). In this study, we investigate SIPS J2045–6332, a potential brown dwarf with significant IR excess in WISE and Two Micron All Sky Survey (2MASS) bands, initially identified by project volunteers. Despite early indicators of a circumstellar disc, discrepancies between observed brightness and expected spectral energy distribution (SED) models suggested unusual properties. To explore potential explanations, we created SED templates for spectral types M9 to L4 and compared them with SIPS J2045–6332’s photometric data, revealing an excess brightness that points to either an unresolved low-mass companion or a young, inflated primary star. Further analysis of IR spectral features and surface gravity indicators supports a youthful classification, estimating the object’s age at 26–200 million years. Observations also suggest the presence of a mid L-type companion at a projected distance of 6.7 au. This study highlights SIPS J2045–6332 as an intriguing system with unique IR characteristics and recommends follow-up observations with high-resolution telescopes to confirm the companion hypothesis and further characterize the system.
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- Award ID(s):
- 2238468
- PAR ID:
- 10674135
- Publisher / Repository:
- Monthly Notices of the Royal Astronomical Society
- Date Published:
- Journal Name:
- Monthly Notices of the Royal Astronomical Society
- Volume:
- 538
- Issue:
- 2
- ISSN:
- 0035-8711
- Page Range / eLocation ID:
- 1019 to 1028
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript
- Journal Article:
- https://doi.org/10.1093/mnras/staf360
