6 papers
Accretion-Mode Transition: The Driver Behind Spectral Changes in Changing-Look AGNs
Pengyuan Han, Huaiyuan Lu, Bing Lyu +2
The physical origin of optical changing-look AGNs (CLAGNs), characterized by the appearance or disappearance of broad emission lines, is thought to be mainly driven by the variatio…
Composite spectrum of Little Red Dot from a standard inner disk and an unstable outer disk
Chenxuan Zhang, Qingwen Wu, Xiao Fan +6
James Webb Space Telescope (JWST) has revealed a new class of high-redshift, very red, compact broad-line sources, termed as "little red dots" (LRDs). The physical mechanism drivin…
A new variability pattern in GRS 1915+105 with NICER and Insight-HXMT observations
Zhihong Shi, Qingwen Wu, Zhen Yan +2
We explore the timing and spectral properties of GRS 1915+105 based on X-ray observations of NICER and Insight-HXMT during the long outburst from 2017 to 2021. We find a new class…
A Composite Broad-Line Region in SDSS J1609+4902: a Double-Peaked Disk component and a Gaussian Component
Jiancheng Wu, Qingwen Wu, Chen Hu +6
The profiles of broad emission lines in active galactic nuclei (AGNs) provide critical insights into the geometry and kinematics of the broad-line region (BLR), which in turn influ…
The NuSTAR view of five changing-look active galactic nuclei
Bing Lyu, Zhen Yan, Xue-bing Wu +3
Changing-look active galactic nuclei (CLAGNs) are known to change their spectral type between 1 and 2 (changing-state) or change their absorption between Compton-thick and Compton-…
The changing-look AGN SDSS J101152.98+544206.4 is returning to a type I state
Bing Lyu, Xue-Bing Wu, Yuxuan Pang +11
Aims. We reported the discovery that a changing-look AGN SDSS J101152.98+544206.4 (J1011+5442 for short) gradually returns to the type 1 state after a short period between 2014 and…