Search Publications
Spatially-resolved stellar population properties of the M51-NGC 5195 system from multi-wavelength photometric data
Kong, Xu; Zou, Hu; Lin, Lin +5 more
Using multi-band photometric images of M51 and its companion NGC 5195 from ultraviolet to optical and infrared, we investigate spatially resolved stellar population properties of this interacting system with stellar population synthesis models. The observed infrared excess (IRX) is used to constrain dust extinction. Stellar mass is also inferred f…
The composite X-ray spectra of radio-loud and radio-quiet SDSS quasars
Gu, Min-Feng; Zhou, Min-Hua
We present a study of the X-ray emission for a sample of radio-detected quasars constructed from the cross-matches between SDSS, FIRST catalogs and XMM-Newton archives. A sample of radio-quiet SDSS quasars without FIRST radio detection is also assembled for comparison. We construct the optical and X-ray composite spectra normalized at rest frame 4…
X-ray spectral evolution in an X-ray changing-look AGN NGC 1365 with variable column density
Liu, Hao; Yang, Jun; Wang, Ting-Gui +4 more
X-ray changing-look active galactic nuclei (CL AGNs) are a subpopulation of AGNs, whose line-of-sight column densities increase/decrease within several years. The physical mechanism for the variation of column density is unclear. We reduce the X-ray data from XMM-Newton and NuSTAR observations for a CL AGN NGC 1365 with strong variation of column …
What causes the absence of pulsations in Central Compact Objects in supernova remnants?
Xiao, Guang-Cheng; Schwope, Axel; Ji, Li +3 more
Most young neutron stars belonging to the class of Central Compact Objects (CCOs) in supernova remnants do not have known periodicities. We investigated seven such CCOs to understand the common reasons for the absence of detected pulsations. Making use of XMM-Newton, Chandra, and NICER observations, we perform a systematic timing and spectral anal…