7 papers
In the Eye of the Storm: The Third Giant X-ray Outburst of the Extreme Changing-look AGN IC 3599
D. Grupe, S. Komossa, W. Zheng +10
We report the discovery and multiwavelength follow-up observations of a giant (factor >100) X-ray outburst of the exceptional changing-look active galactic nucleus (AGN) IC 3599. T…
OQ~208: A New Fe~II Changing-look Active Galactic Nucleus and Implications for the Nature of the Changing-look Phenomenon
J. Wang, W. K. Zheng, D. W. Xu +5
In addition to the traditional hydrogen Balmer emission lines, here we extend the optical changing-look (CL) phenomenon occurring in some active galactic nuclei (AGNs) to the optic…
SDSSJ110546.07+145202.4: The first long-duration radio changing-look NLS1 galaxy
S. Komossa, D. Grupe, A. Kraus +12
SDSSJ110546.07+145202.4 stands out as a unique radio changing-look Narrow-line Seyfert 1 (NLS1) galaxy that has brightened dramatically and shows an exceptionally long duration of…
Are "Changing-Look" Active Galactic Nuclei Special in the Coevolution of Supermassive Black Holes and their Hosts? II. The Case of Changing-Look Narrow-Line Seyfert 1 Galaxies
J. Wang, S. Jin, D. W. Xu +5
The evolutionary role of the so-called ``changing-look'' (CL) active galactic nucleus (AGN), which is characterized by spectral-type transitions within yr, has been sugges…
Characterizing Candidate Blazar Counterparts of the Ultra-High-Energy Event KM3-230213A
KM3NeT Collaboration, MessMapp Group, LAT Collaboration +13
High-energy astrophysical neutrinos serve as crucial messengers for understanding hadronic acceleration processes and identifying the origins of cosmic rays, with blazars among the…
Picking-up Local GRB Candidates Based on Their Host Galaxies
J. Wang, Y. Xu, L. J. Chen +4
Rapid identification of candidates of high-value gamma-ray bursts (GRBs), including both high- and local events, is crucial for outlining subsequent observational strategy. In t…