121 citations · 1k across the 48 of their papers we have counts for
8 papers · 1 filter
R-matrix electron-impact excitation data for the H- and He-like ions with Z=6-30
Junjie Mao, G. Del Zanna, Liyi Gu +2
Plasma models built on extensive atomic data are essential to interpreting the observed cosmic spectra. H-like Lyman series and He-like triplets observable in the X-ray band are po…
Multi-wavelength observations of the obscuring wind in the radio-quiet quasar MR 2251-178
Junjie Mao, G. A. Kriss, H. Landt +11
Obscuring winds driven away from active supermassive black holes are rarely seen due to their transient nature. They have been observed with multi-wavelength observations in a few…
Searching for cataclysmic variable stars in unidentified X-ray sources
J. Takata, X. F. Wang, A. K. H. Kong +6
We carry out a photometric search for new cataclysmic variable stars (CVs), with the goal of identification for candidates of AR~Scorpii-type binary systems. We select GAIA sources…
10-Year Transformation of the Obscuring Wind in NGC 5548
Missagh Mehdipour, Gerard A. Kriss, Elisa Costantini +4
A decade ago the archetypal Seyfert-1 galaxy NGC 5548 was discovered to have undergone major spectral changes. The soft X-ray flux had dropped by a factor of 30 while new broad and…
Detection of an Unidentified Soft X-ray Emission Feature in NGC 5548
Liyi Gu, Junjie Mao, Jelle S. Kaastra +17
NGC~5548 is an X-ray bright Seyfert 1 active galaxy. It exhibits a variety of spectroscopic features in the soft X-ray band, including in particular the absorption by the AGN outfl…
X-ray spectra of the Fe-L complex III: systematic uncertainties in the atomic data
Liyi Gu, Chintan Shah, Junjie Mao +14
There has been a growing request from the X-ray astronomy community for a quantitative estimate of systematic uncertainties originating from the atomic data used in plasma codes. T…