26 citations · 141 across the 16 of their papers we have counts for
16 papers
OzSSy1: The Australian Southern Seyfert-1 Spectroscopic Atlas and Catalogue at z < 0.1
Neelesh Amrutha, Christian Wolf, Christopher A. Onken +3
We present a spectroscopic atlas of 887 broad-line active galactic nuclei (AGNs) in the Southern sky, spanning redshifts , declinations deg and Galactic latitudes $…
A catalogue of Type 2 active galactic nuclei in the 6dF Galaxy Survey
Sruthi Suresh, Wei Jeat Hon, Rachel L Webster +2
Active galactic nuclei (AGNs) are the compact, energetic central regions of galaxies, powered by supermassive black holes that accrete surrounding gas and dust. Their optical spect…
Discovering Changing-Look AGN in the 6dF Galaxy Survey using ATLAS Light curves
Neelesh Amrutha, Christian Wolf, Christopher A. Onken +4
Changing-Look Active Galactic Nuclei (CLAGN) are characterised by extreme variations in line emission over short timescales, mostly affecting broad H lines. While a few hundred…
Broad-line Active Galactic Nuclei in the 6dF Galaxy Survey
Wei Jeat Hon, Rachel Webster, Christian Wolf
The Six-degree Field Galaxy Survey (6dFGS) is a spectroscopic redshift survey of the Southern hemisphere completed in 2006. While it provides 136,304 spectra of mostly low-redshift…
The accretion of a solar mass per day by a 17-billion solar mass black hole
Christian Wolf, Samuel Lai, Christopher A. Onken +5
Around a million quasars have been catalogued in the Universe by probing deeper and using new methods for discovery. However, the hardest ones to find seem to be the rarest and bri…
A redshifted excess in the broad emission lines after the flare of the -ray narrow-line Seyfert 1 PKS 2004-447
W. Hon, M. Berton, E. Sani +6
PKS 2004-447 is a narrow-line Seyfert 1 (NLS1) harbouring a relativistic jet with gamma-ray emission. On 2019-10-25, the Fermi-Large Area Telescope captured a -ray flare from th…
AllBRICQS: the All-sky BRIght, Complete Quasar Survey
Christopher A. Onken, Christian Wolf, Wei Jeat Hon +3
We describe the first results from the All-sky BRIght, Complete Quasar Survey (AllBRICQS), which aims to discover the last remaining optically bright quasars. We present 156 spectr…
Discovery of the most luminous quasar of the last 9 Gyr
Christopher A. Onken, Samuel Lai, Christian Wolf +8
We report the discovery of a bright (g = 14.5 mag (AB), K = 11.9 mag (Vega)) quasar at redshift z = 0.83 -- the optically brightest (unbeamed) quasar at z > 0.4. SMSS J114447.77-43…
Finding Quasars behind the Galactic Plane. II. Spectroscopic Identifications of 204 Quasars at
Yuming Fu, Xue-Bing Wu, Linhua Jiang +21
Quasars behind the Galactic plane (GPQs) are important astrometric references and valuable probes of Galactic gas, yet the search for GPQs is difficult due to severe extinction and…
SkyMapper colours of Seyfert galaxies and Changing-look AGN-II. Newly discovered Changing-look AGN
Wei Jeat Hon, Christian Wolf, Christopher Onken +2
Changing-look Active Galactic Nuclei (CLAGN) are AGN that change type as their broad emission lines appear or disappear, which is usually accompanied by strong flux changes inn the…
Ultra-luminous high-redshift quasars from SkyMapper -- II. New quasars and the bright end of the luminosity function
Christopher A. Onken, Christian Wolf, Fuyan Bian +5
We search for ultra-luminous Quasi-Stellar Objects (QSOs) at high redshift using photometry from the SkyMapper Southern Survey Data Release 3 (DR3), in combination with 2MASS, VHS…
A Systematic Survey for z < 0.04 Changing-Look AGNs
Madhooshi R. Senarath, Michael J. I. Brown, Michelle E. Cluver +6
We have conducted a systematic survey for z 0.04 active Galactic nuclei (AGNs) that may have changed spectral class over the past decade. We use SkyMapper, Pan-STARRS and the V…
SkyMapper colours of Seyfert galaxies and Changing-Look AGN
Christian Wolf, Jacob Golding, Wei Jeat Hon +1
We study the utility of broad-band colours in the SkyMapper Southern Survey for selecting Seyfert galaxies at low luminosity. We find that the index, built from the ultraviol…
Ultra-luminous quasars at redshift from SkyMapper
Christian Wolf, Wei Jeat Hon, Fuyan Bian +6
The most luminous quasars at high redshift harbour the fastest-growing and most massive black holes in the early Universe. They are exceedingly rare and hard to find. Here, we pres…
Discovery of the most ultra-luminous QSO using Gaia, SkyMapper and WISE
Christian Wolf, Fuyan Bian, Christopher A. Onken +5
We report the discovery of the ultra-luminous QSO SMSS~J215728.21-360215.1 with magnitude and W4 at redshift 4.75. Given absolute magnitudes of $M_{145,\rm AB}=-29.…
Discovery of two bright quasars with SkyMapper, Pan-STARRS1 and WISE
Zefeng Li, Christian Wolf, Fuyan Bian +5
We present a search for bright quasars using imaging data from SkyMapper Southern Survey, Pan-STARRS1 and the Wide-field Infrared Survey Explorer (WISE). We select two set…