Search Publications
The Distribution of UV Radiation Field in the Molecular Clouds of Gould Belt
Li, Di; Xie, Jinjin; Fuller, Gary A. +5 more
The distribution of ultraviolet (UV) radiation field provides critical constraints on the physical environments of molecular clouds. Within 1 kpc of our solar system and fostering protostars of different masses, the giant molecular clouds in the Gould Belt present an excellent opportunity to resolve the UV field structure in star-forming regions. …
Revisiting the Evidence for an Intermediate-mass Black Hole in the Center of NGC 6624 with Simulations
Wang, Li-Chun; Xie, Yi
The acceleration of LMXB 4U 1820-30 derived from its orbital-period derivative ${\dot{P}}_{{\rm{b}}}$ was supposed to be the evidence for an Intermediate-mass black hole (IMBH) in the Galactic globular cluster (GC) NGC 6624. However, we find that the anomalous ${\dot{P}}_{{\rm{b}}}$ is mainly due to the gravitational wave emission, rather than the…
Precise Positions of Triton in 2010-2014 based on Gaia-DR2
Yu, Yong; Tang, Kai; Zhang, Huiyan +2 more
With unique orbital and physical characteristics, Triton is a very important target because it may contain information of the origin and evolution of the solar system. Besides space explorations, ground-based observations over long time also play a key role on research of Triton. High-precision positions of Triton obtained from ground telescopes a…
New Massive Contact Twin Binary in a Radio-quiet H II Region Associated with the M17 Complex
Chen, Zhiwei; Jiang, Zhibo; Yin, Jia +3 more
Early-B stars, much less energetic than O stars, may create an H II region that appears as radio-quiet. We report the identification of new early-B stars associated with the radio-quiet H II region G014.645-00.606 in the M17 complex. The radio-quiet H II region G014.645-00.606 is adjacent to three radio-quiet WISE H II region candidates. The ioniz…
A New Statistical Distance Scale for Planetary Nebulae, Based on Gaia EDR3
Ali, A.; Mindil, A.; Alghamdi, S. A. +1 more
The present work aims to build a new statistical distance scale for planetary nebulae (PNe) based on a rigorous calibration sample. The distances of the calibration sample are derived from the trigonometric parallax method using the recent measurements of Gaia Early Data Release 3 (Gaia EDR3). The new distance scale is created by applying the well…
A Study on White Dwarf Masses in Cataclysmic Variables Based on XMM-Newton and Suzaku Observations
Li, Xiang-Dong; Xu, Xiao-Jie; Yu, Zhuo-Li
The distribution of the mass of white dwarfs (WDs) is one of the fundamental questions in the field of cataclysmic variables (CVs). In this work, we make a systematical investigation on the WD masses in two subclass of CVs: intermediate polars (IPs) and non-magnetic CVs in the solar vicinity based on the flux ratios of Fe XXVI-Lyα to Fe XXV-Heα em…
Mapping of Compositional Diversity and Chronological Ages of Lunar Farside Multiring Mare Moscoviense Basin: Implications to the Middle Imbrian Mare Basalts
Sharma, Manish; Karthi, A.; Arivazhagan, S.
The Mare Moscoviense is an astonishing rare flatland multi-ring basin and one of the recognizable mare regions on the Moon's farside. The mineralogical, chronological, topographical and morphological studies of the maria surface of the Moon provide a primary understanding of the origin and evolution of the mare provinces. In this study, the Chandr…
Effects of Binaries on Open Cluster Age Determination in Bayesian Inference
Chen, Jing; Zhang, Su; Li, Zhong-Mu +2 more
We investigate the effects of binaries on the cluster age determination for 561 open clusters in the Galactic disk via the Bayesian statistical framework. Stellar properties of these star clusters, including age, metallicity, distance modulus, color excess, binary fraction, and rotating star fraction, are derived from color-magnitude-diagrams (CMD…
The Origin of The Soft X-Ray Excess in the Seyfert 1.5 Galaxy ESO 362-G18
Zhong, Xiao-Gu; Wang, Jian-Cheng
We review the Seyfert 1.5 Galaxy ESO 362-G18 for exploring the origin of the soft X-ray excess. The Warm Corona and Relativistic Reflection models are two main scenarios to interpret the soft X-ray excess in active galactic nuclei at present. We use the simultaneous X-ray observation data of XMM-Newton and NuSTAR on 2016 September 24 to perform sp…
Evaluating Helium Variations By Modeling Red Giant Branch Bump of Large Magellanic Cluster NGC 1978
Li, Cheng-Yuan; Ji, Xin; Deng, Li-Cai
Many evidences show that the Multiple Population (MP) features exist not only in old clusters but also in intermediate-age clusters in the Megallanic Clouds (MCs), which are characterized by star-to-star abundance scatter of several elements, including helium (He). The red giant branch bump (RGBB)'s photometric properties are proved to be related …