Red synchrotron jets in Parkes quasars

Abstract

We present model fits to spectral energy distributions in the optical and NIR of >100 flat-spectrum radio quasars from the Parkes Half-Jansky Flat-spectrum Sample. We find that approximately 40% of the sources have power-law SEDs, while a similar number show evidence for two primary components: a blue power law and optical synchrotron emission. The blue power law is similar to the dominant component observed in the spectra of optically-selected QSOs. There is strong evidence that the synchrotron component has a turnover in the UV-optical rest frame of the spectrum. In the remaining sources it is likely that the synchrotron peaks at longer wavelengths. This mixture of two components is supported by optical polarisation measurements in a subgroup of the sources. The sources with power law SEDs show evidence for an excess number of red power law slopes compared to optically-selected quasars. There are additional spectral components in some of the sources, such as dust and the underlying galaxy, which have not been considered here.

MNRAS, in press; 16 pages, 13 figures

Cited by in corpus (40)

• Red and Reddened Quasars in the Sloan Digital Sky Survey
• A Population of Radio-loud Narrow Line Seyfert 1 Galaxies with Blazar-like Properties?
• Fitting AGN/galaxy X-ray-to-radio SEDs with CIGALE and improvement of the code
• FIRST-2MASS Red Quasars: Transitional Objects Emerging from the Dust
• The FIRST-2MASS Red Quasar Survey
• Black hole mass estimation with a relation between the BLR size and emission line luminosity of AGN
• The Reddest Quasars
• Heavily reddened type 1 quasars at z > 2 I: Evidence for significant obscured black-hole growth at the highest quasar luminosities
• FIRST-2MASS Sources Below the APM Detection Threshold: A Population of Highly Reddened Quasars
• The Spitzer mid-infrared AGN survey. I - optical and near-infrared spectroscopy of candidate obscured and normal AGN selected in the mid-infrared
• Black Hole Mass Estimates of Radio Selected Quasars
• Fundamental differences in the radio properties of red and blue quasars: evolution strongly favoured over orientation
• The Optical - Infrared Colors of CORALS QSOs: Searching for Dust Reddening Associated With High Redshift Damped Lyman Alpha Systems
• Partially obscured quasars in the Sloan Digital Sky Survey Early Data Release
• An I-Band-Selected Sample of Radio-Emitting Quasars: Evidence for a Large Population of Red Quasars
• The multiwavelength properties of red QSOs -- Evidence for dusty winds as the origin of QSO reddening
• HI 21-cm absorption and unified schemes of active galactic nuclei
• Fundamental differences in the radio properties of red and blue quasars: enhanced compact AGN emission in red quasars
• The Disc-Jet Relation in Strong-Lined Blazars
• Are red 2MASS QSOs young?
• Accretion Rates of Red Quasars from the Hydrogen P$\beta$ line
• Chandra Observations of 12 Luminous Red Quasars
• What makes red quasars red? Observational evidence for dust extinction from line ratio analysis
• An Unbiassed Census of Active Galactic Nuclei in the Two Micron All Sky Survey
• Broad line region and black hole mass of PKS 1510-089 from spectroscopic reverberation mapping
• Fundamental differences in the properties of red and blue quasars: measuring the reddening and accretion properties with X-shooter
• The Reddest DR3 SDSS/XMM Quasars
• An ASKAP survey for HI absorption towards dust-obscured quasars
• Estimators of Bolometric Luminosity and Black Hole Mass with Mid-infrared Continuum Luminosities for Dust-obscured Quasars: Prevalence of Dust-obscured SDSS Quasars
• Medium-resolution Optical and Near-Infrared Spectral Atlas of 16 2MASS-selected NIR-red Active Galactic Nuclei at $z\sim 0.3$
• A young, dusty, compact radio source within a Ly|*alpha*| halo
• A multi-wavelength survey of AGN in the XMM-LSS field: I. Quasar selection via the KX technique
• uGMRT search for cold gas at z~1-1.4 towards red quasars
• Eddington Ratios of Dust-obscured Quasars at $z\lesssim 1$: Evidence Supporting Dust-obscured Quasars as Young Quasars
• The Optical Emission from Gamma-ray Quasars
• Rest-frame optical continua of L ~ L*, z>3 quasars: probing the faint end of the high z quasar luminosity function
• Near-infrared micro-variability of radio-loud quasars
• Properties of spectrally-defined red QSOs at z = 0.3-1.2
• Stochastic Absorption of the Light of Background Sources due to Intergalactic Neutral Hydrogen I. Testing different line-number evolution models via the cosmic flux decrement
• VLBI observations of a flared optical quasar CGRaBS J0809+5341