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Showing papers by "Carol J. Lonsdale published in 2013"


Journal ArticleDOI
TL;DR: In this article, the authors present near-infrared spectra of young radio quasars [P(1.4GHz) ~ 26-27 W/Hz] selected from the Wide-Field Infrared Survey Explorer.
Abstract: We present near-infrared spectra of young radio quasars [P(1.4GHz) ~ 26-27 W/Hz] selected from the Wide-Field Infrared Survey Explorer. The detected objects have typical redshifts of z ~ 1.6-2.5 and bolometric luminosities ~ 10^47 erg/s. Based on the intensity ratios of narrow emission lines, we find that these objects are mainly powered by active galactic nuclei (AGNs), although star formation contribution cannot be completely ruled out. The host galaxies experience moderate levels of extinction, A(V) ~ 0-1.3 mag. The observed [O III] luminosities and rest-frame J-band magnitudes constrain the black hole masses to lie in the range ~ 10^8.9-10^9.7 solar mass. From the empirical correlation between black hole mass and host galaxy mass, we infer stellar masses of ~ 10^11.3-10^12.2 solar mass. The [O III] line is exceptionally broad, with full width at half maximum ~1300 to 2100 km/s, significantly larger than that of ordinary distant quasars. We argue that these large line widths can be explained by jet-induced outflows, as predicted by theoretical models of AGN feedback.

30 citations


Journal ArticleDOI
TL;DR: In this paper, the authors presented radio continuum mapping, optical imaging and spectroscopy of the newly discovered double-peaked broad-lined AGN W2332-5056, which exhibits an FR-I and FR-II hybrid-morphology, characterized by bright core, jet and Doppler boosted lobe structures in ATCA continuum maps at 1.5, 5.6, and 9 GHz.
Abstract: We present radio continuum mapping, optical imaging and spectroscopy of the newly discovered double-peaked broad-lined AGN WISE J233237.05-505643.5 at redshift z = 0.3447. This source exhibits an FR-I and FR-II hybrid-morphology, characterized by bright core, jet, and Doppler-boosted lobe structures in ATCA continuum maps at 1.5, 5.6, and 9 GHz. Unlike most FR-II objects, W2332-5056 is hosted by a disk-like galaxy. The core has a projected 5" linear radio feature that is perpendicular to the curved primary jet, hinting at unusual and complex activity within the inner 25 kpc. The multi-epoch optical-near-IR photometric measurements indicate significant variability over a 3-20 year baseline from the AGN component. Gemini-South optical data shows an unusual double-peaked emission-line features: the centroids of the broad-lined components of H-alpha and H-beta are blueshifted with respect to the narrow lines and host galaxy by ~ 3800 km/s. We examine possible cases which involve single or double supermassive black holes in the system, and discuss required future investigations to disentangle the mystery nature of this system.

16 citations