Search Publications
The Variability and Radial Velocity of Planetary Nebula Central Stars
Ali, A.; Mindil, A.
The extremely accurate estimates of stellar variability and radial velocity in the Gaia Data Release 3 (Gaia DR3) have enabled us to examine the close binarity and radial velocity (RV) of central stars (CSs) of planetary nebulae (PNe). This study is twofold: (1) searching for new close binary CS candidates to better understand how binarity affects…
Possible Detection of a Flare-associated Coronal Mass Ejection on an M-dwarf
Wang, J.
We here report a probable detection of a stellar coronal mass ejection (CME) in active M dwarf KIC 8093473 by performing an analysis on its time resolved X-ray spectra observed by the XMM-Newton satellite. Compared to the value at the quiescent state and the interstellar one, our spectral modeling returns a marginal (and probably evolving) excess …
A Morphological Study of Two Young Multipolar Planetary Nebulae
Hsia, Chih-Hao; Kang, Xiao-Xi; Wen, Shi-Bo +2 more
We carry out an optical morphological and infrared spectral study for two young planetary nebulae (PNs) Hen 2-158 and Pe 1-1 to understand their complex shapes and dust properties. Hubble Space Telescope optical images reveal that these nebulae have several bipolar-lobed structures and a faint arc with a clear boundary is located at the northweste…
Spatially Resolved Properties of the GW170817 Host Galaxy
Li, Yubin; Mao, Jirong; Zhao, Yinghe +4 more
GW170817 is the unique gravitational-wave (GW) event associated with the electromagnetic (EM) counterpart GRB 170 817A. NGC 4993 is identified as the host galaxy of GW170817/GRB 170 817A. In this paper, we focus on the spatially resolved properties of NGC 4993. We present the photometric results from the comprehensive data analysis of the high spa…
Reciprocating Magnetic Fields in the Pulsar Wind Observed from the Black Widow Pulsar J1720-0534
Wang, Shen; Li, Di; Kramer, M. +41 more
We report the radio observations of the eclipsing black widow pulsar J1720-0534, a 3.26 ms pulsar in orbit with a low mass companion of mass 0.029 to 0.034 M ⊙. We obtain the phase-connected timing ephemeris and polarization profile of this millisecond pulsar (MSP) using the Five-hundred-meter Aperture Spherical radio Telescope (FAST), …
NGC 4117: A New Compton-thick AGN Revealed by Broadband X-Ray Spectral Analysis
Mohanadas, Pavithra; Annuar, Adlyka
In this paper, we present the broadband (0.5-195 keV) X-ray spectral analysis for one of the newly detected AGNs in the Swift-BAT 105 month Hard X-ray Survey Catalog, NGC 4117. According to our ongoing research on low luminosity AGNs from the Swift-BAT 105 month catalog, we examine whether they are indeed low luminosity or heavily obscured AGNs. O…
A Catalog of Collected Debris Disks: Properties, Classifications and Correlations between Disks and Stars/Planets
Liu, Qiong; Liao, Neng-Hui; Cao, Peng-Cheng +2 more
We have collected a catalog of 1095 debris disks with properties and classification (resolved, planet, gas) information. From the catalog, we defined a less biased sample with 612 objects and presented the distributions of their stellar and disk properties to search for correlations between disks and stars. We found debris disks were widely distri…
Speckle-interferometric Study of Close Visual Binary System HIP 11253 (HD 14874) using Gaia (DR2 and EDR3)
Taani, Ali; Aljboor, Hussam
We present a comprehensive set of physical and geometrical parameters for each of the components of the close visual binary system HIP 11253 (HD 14874). We present an analysis for the binary and multiple stellar systems with the aim to obtain a match between the overall observational spectral energy distribution of the system and the spectral synt…
A Two-limb Explanation for the Optical-to-infrared Transmission Spectrum of the Hot Jupiter HAT-P-32Ab
Chen, Guo; Wang, Hong-Chi; Zhao, Hai-Bin +1 more
We present a new optical transmission spectrum of the hot Jupiter HAT-P-32Ab acquired with the Carnegie Observatories Spectrograph and Multiobject Imaging Camera (COSMIC) on the Palomar 200 inch Hale Telescope (P200). The P200/COSMIC transmission spectrum, covering a wavelength range of 3990-9390 Å, is composed of 25 spectrophotometric bins with w…
Sodium Abundances in Very Metal-poor Stars
Shi, Jianrong; Zhao, Gang; Li, Haining +9 more
Chemical composition of very metal-poor (VMP) stars can provide observational constraints on current models of nucleosynthesis and the chemical evolution of the Galaxy. It has been found that the scatter of [Na/Fe] versus [Fe/H] in VMP stars is very large in contrast with most other elements. Moreover, a negative slope in [Na/Fe] versus [Fe/H] was…