Search Publications
Type Ia Supernova Explosions in Binary Systems: A Review
Han, Zhanwen; Liu, Zheng-Wei; Röpke, Friedrich K.
Type Ia supernovae (SNe Ia) play a key role in the fields of astrophysics and cosmology. It is widely accepted that SNe Ia arise from thermonuclear explosions of white dwarfs (WDs) in binary systems. However, there is no consensus on the fundamental aspects of the nature of SN Ia progenitors and their actual explosion mechanism. This fundamentally…
The Masses of a Sample of Radial-velocity Exoplanets with Astrometric Measurements
Zhao, Gang; Wang, Wei; Xiao, Guang-Yao +6 more
Being one of the most fundamental physical parameter of astronomical objects, mass plays a vital role in the study of exoplanets, including their temperature structure, chemical composition, formation, and evolution. However, nearly a quarter of the known confirmed exoplanets lack measurements of their masses. This is particularly severe for those…
Hubble WFC3 Spectroscopy of the Terrestrial Planets L 98-59 c and d: No Evidence for a Clear Hydrogen Dominated Primary Atmosphere
Zhu, Yi-Nan; Zhou, Li; Ma, Bo +1 more
The nearby bright M-dwarf star L 98-59 has three terrestrial-sized planets. One challenge remaining in characterizing atmospheres around such planets is that it is not known a priori whether they possess any atmospheres. Here we report on study of the atmospheres of L 98-59 c and L 98-59 d using near-infrared spectral data from the G141 grism of H…
Classifying Globular Clusters and Applying them to Estimate the mass of the Milky Way
Gao, Qi; Liu, Chao; Chen, Xuelei +3 more
We combine the kinematics of 159 globular clusters (GCs) provided by the Gaia Early Data Release 3 (EDR3) with other observational data to classify the GCs, and to estimate the mass of the Milky Way (MW). We use the age-metallicity relation, integrals of motion, action space and the GC orbits to identify the GCs as either formed in situ (Bulge and…
Detection of TiO and VO in the Atmosphere of WASP-121b and Evidence For its Temporal Variation
Zhao, Gang; Wang, Wei; Zhao, Fei +6 more
We report the transit observations of the ultra-hot Jupiter WASP-121b using the Goodman High Throughput Spectrograph at the 4 m ground-based Southern Astrophysical Research Telescope, covering the wavelength range 502-900 nm. By dividing the target and reference star into 19 spectroscopic passbands and applying differential spectrophotometry, we d…
Atmospheric Parameters and Kinematic Information for the M Giant Stars from LAMOST DR9
Qiu, Dan; Tian, Hao; Yang, Ming +5 more
A catalog of more than 43,000 M giant stars has been selected by Li et al. from the ninth data release of LAMOST. Using the data-driven method SLAM, we obtain the stellar parameters (T eff, $\mathrm{log}\,g$ , [M/H], [α/M]) for all the M giant stars with uncertainties of 57 K, 0.25 dex, 0.16 dex and 0.06 dex at SNR > 100, respectivel…
3D Kinematics of Classical Cepheids According to Gaia EDR3 Catalog
Bobylev, V. V.; Bajkova, A. T.
The kinematics of about 2000 classical Cepheids of the Milky Way with data from Gaia EDR3 catalog has been studied. For some of these stars, there are line-of-sight velocities. On the basis of the nonlinear rotation model, the parameters of the rotation curve of the Galaxy were determined. The circular linear rotation velocity of the near-solar ne…
The Unusual AGN Host NGC 1266: Evidence for Shocks in a Molecular Gas Rich S0 Galaxy with a Low Luminosity Nucleus
Wang, Junfeng; Zhao, Yinghe; Chen, Peibin
NGC 1266 is a lenticular galaxy (S0) hosting an active galactic nucleus (AGN), and known to contain a large amount of shocked gas. We compare the luminosity ratio of mid-J CO lines to IR continuum with star-forming galaxies (SFGs), and then model the CO spectral line energy distribution (SLED). We confirm that in the mid- and high-J regions (J
Global Energetics of Solar Powerful Events on 2017 September 6
Lu, Lei; Dresing, Nina; Wang, Jincheng +9 more
Solar flares and coronal mass ejections (CMEs) are thought to be the most powerful events on the Sun. They can release energy as high as ~1032 erg in tens of minutes, and also can release solar energetic particles (SEPs) into interplanetary space. We explore global energy budgets of solar major eruptions that occurred on 2017 September …
Photometric Properties and Stellar Parameters of the Rapidly Rotating Magnetic Early-B Star HD 345439
Zhang, Yu; Liu, Jin-Zhong; Li, Lei +8 more
We first present the multicolor photometry results of the rapidly rotating magnetic star HD 345439 using the Nanshan One-meter Wide-field Telescope. From the photometric observations, we derive a rotational period of 0.7699 ± 0.0014 day. The light curves of HD 345439 are dominated by the double asymmetric S-wave feature that arises from the magnet…