41 citations · 75 across the 12 of their papers we have counts for
11 papers · 1 filter
Emission-line Variable Active Galactic Nuclei at Cosmic Noon from HETDEX
Chenxu Liu, Fanchuan Kong, Erin Mentuch Cooper +11
We present the first statistical census of emission-line variable active galactic nuclei (EVA) at cosmic noon by combining untargeted and deep HETDEX spectroscopy with multi-epoch…
Extreme line profile variations in the repeating changing-look active galactic nucleus IRAS23226-3843
Wolfram Kollatschny, Dirk Grupe, Hartmut Winkler +7
IRAS23226-3843 has been identified as a highly variable Seyfert galaxy and even as a changing-look active galactic nucleus based on optical spectra. Here we present follow-up obser…
First reverberation mapping of a Bowen fluorescence line
Martin W. Ochmann, Edward M. Cackett, Lukas Diehl +3
Reverberation mapping (RM) is a powerful tool to determine the extent, structure, and kinematics of the broad-line region (BLR) of active galactic nuclei (AGN). So far, RM of the B…
Emission-Line and Continuum Reverberation Mapping of the NLS1 Galaxy WPVS 48
M. A. Probst, W. Kollatschny, M. W. Ochmann +6
WPVS 48 is a nearby narrow-line Seyfert 1 galaxy without previous analysis of the broad-line region (BLR) by means of optical spectroscopic reverberation mapping. By studying the c…
Multiwavelength continuum, emission line and BAL variability with prominent PV absorption in the X-ray-weakest quasar PG0043+039
Wolfram Kollatschny, Norbert Schartel, Malte A. Probst +3
PG0043+039 has been identified as an extremely X-ray-weak quasar and as a peculiar broad-absorption-line quasar based on UV HST spectra. We took simultaneous deep X-ray observation…
Long Term Reverberation Mapping of Iron Coronal Lines in MKN 110
Charles Yin, Andy Lawrence, Martin Ward +2
We present flux measurements of the coronal lines [Fe VII] and [Fe X] spanning three decades, in the highly variable Active Galactic Nucleus (AGN) MKN 110. These coronal lines are…
Double-peaked Ca II traces a relativistic broad-line region disk in NGC 4593
M. W. Ochmann, P. M. Weilbacher, M. A. Probst +7
Double-peaked emission lines are observed in a small percentage of active galactic nuclei (AGN). These lines allow the determination of properties of the line-emitting region, know…
Evidence for gravitational self-lensing of the central supermassive black hole binary in the Seyfert galaxy NGC 1566
Wolfram Kollatschny, Doron Chelouche
It is generally accepted that all massive galaxies host supermassive black holes (BHs) in their center and that mergers of two galaxies lead to the formation of BH binaries. The mo…
Changing-look NLS1 galaxies, their detection with SVOM, and the case of NGC 1566
D. W. Xu, S. Komossa, D. Grupe +15
We discuss applications of the study of the new and barely explored class of changing-look (CL) narrow-line Seyfert 1 (NLS1) galaxies and comment on their detection with the space…
Proving strong magnetic fields near to the central black hole in the quasar PG0043+039 via cyclotron lines
W. Kollatschny, N. Schartel, M. Zetzl +3
The optical luminous quasar PG0043+039 has not been detected before in deep X-ray observations indicating the most extreme optical-to-X-ray slope index of all quasars. Thi…
Broad-line region structure and kinematics in the radio galaxy 3C 120
W. Kollatschny, K. Ulbrich, M. Zetzl +2
Broad emission lines originate in the surroundings of supermassive black holes in the centers of active galactic nuclei (AGN). One method to investigate the extent, structure, and…