How does the radio enhancement of broad absorption line quasars relate to colour and accretion rate?

Petley, James W; Morabito, Leah K; Rankine, Amy L; Richards, Gordon T; Thomas, Nicole L; Alexander, David M; Fawcett, Victoria A; Calistro Rivera, Gabriela; Prandoni, Isabella; Best, Philip N; Kolwa, Sthabile

Abstract

The origin of radio emission in different populations of radio-quiet quasars is relatively unknown, but recent work has uncovered various drivers of increased radio-detection fraction. In this work, we pull together three known factors: optical colour (g - i), C IV distance (a proxy for L/LEdd), and whether or not the quasar contains broad absorption lines (BALQSOs) which signify an outflow. We use SDSS (Sloan Digital Sky Survey) DR14 spectra along with the LOFAR Two Metre Sky Survey Data Release 2 and find that each of these properties have an independent effect. BALQSOs are marginally more likely to be radio-detected than non-BALQSOs at similar colours and L/LEdd, moderate reddening significantly increases the radio-detection fraction and the radio detection increases with L/LEdd above a threshold for all populations. We test a widely used simple model for radio wind shock emission and calculate energetic efficiencies that would be required to reproduce the observed radio properties. We discuss interpretations of these results concerning radio-quiet quasars more generally. We suggest that radio emission in BALQSOs is connected to a different physical origin than the general quasar population since they show different radio properties independent of colour and C IV distance.

Citation

Petley, J. W., Morabito, L. K., Rankine, A. L., Richards, G. T., Thomas, N. L., Alexander, D. M., …Kolwa, S. (2024). How does the radio enhancement of broad absorption line quasars relate to colour and accretion rate?. Monthly Notices of the Royal Astronomical Society, 529(3), 1995-2007. https://doi.org/10.1093/mnras/stae626

• Journal Article Type: Article
• Acceptance Date: Feb 28, 2024
• Online Publication Date: Feb 29, 2024
• Publication Date: 2024-04
• Deposit Date: Mar 27, 2024
• Publicly Available Date: Mar 27, 2024
• Journal: Monthly Notices of the Royal Astronomical Society
• Print ISSN: 0035-8711
• Electronic ISSN: 1365-2966
• Publisher: Royal Astronomical Society
• Peer Reviewed: Peer Reviewed
• Volume: 529
• Issue: 3
• Pages: 1995-2007
• DOI: https://doi.org/10.1093/mnras/stae626
• Keywords: Space and Planetary Science; Astronomy and Astrophysics
• Public URL: https://durham-repository.worktribe.com/output/2348688