Search Publications
Kepler main-sequence solar-like stars: surface rotation and magnetic-activity evolution
García, Rafael A.; Breton, Sylvain N.; Mathur, Savita +4 more
While the mission's primary goal was focused on exoplanet detection and characterization, Kepler made and continues to make extraordinary advances in stellar physics. Stellar rotation and magnetic activity are no exceptions. Kepler allowed for these properties to be determined for tens of thousands of stars from the main sequence up to the red gia…
A study on the metallicity gradients in the galactic disk using open clusters
Deepak; Malhotra, Sagar; Joshi, Yogesh Chandra
We study the metallicity distribution and evolution in the galactic disk based on the largest sample of open star clusters in the galaxy. From the catalog of 1,879 open clusters in the range of galactocentric distance (RGC) from 4 to 20 kpc, we investigate the variation in metallicity in the galactic disk as functions of RGC, vertical distance (Z)…
Evaluation of the astrometric capability of Multi-Channel Imager and simulated calculation of proper motion of M31
Peng, Xiyan; Liao, Shilong; Qi, Zhaoxiang +8 more
Introduction: The Multi-Channel Imager (MCI), one of the back-end modules of the future China Space Station Telescope (CSST), is designed for high-precision spacebased astronomical observations. This paper evaluates the astrometric capability of the MCI based on simulated observational images and Gaia data: the M31 galaxy is selected as a represen…
Investigation of a W UMa-type contact binary GZ And in a physical triple system
Zheng, Jie; Jiang, Lin-Qiao
GZ And is a variable star within the visually observed multiple-star system ADS 1693. Recent observations have yielded new light curves for GZ And, obtained using the Xinglong 85-cm telescope and the Transiting Exoplanet Survey Satellite (TESS) satellite. These light curves, along with radial velocity curves, were analyzed simultaneously to ascert…
Simulation of CSST's astrometric capability
Liao, Shi-Long; Qi, Zhao-Xiang; Shao, Li +5 more
Introduction: The China Space Station Telescope (CSST) will enter a low Earth orbit around 2024 and operate for 10 years, with seven of those years devoted to surveying the area of the median-to-high Galactic latitude and median-to-high Ecliptic latitude of the sky. To maximize the scientific output of CSST, it is important to optimize the survey …
MORPHOFIT: An automated galaxy structural parameters fitting package
Tortorelli, Luca; Mercurio, Amata
In today's modern wide-field galaxy surveys, there is the necessity for parametric surface brightness decomposition codes characterised by accuracy, small degree of user intervention, and high degree of parallelisation. We try to address this necessity by introducing \textsc{morphofit}, a highly parallelisable \textsc{python} package for the estim…
On the nature of Tycho Brahe's supernova
Ruiz-Lapuente, Pilar
At the 450 years anniversary of its observation, the supernova named after Tycho Brahe, SN 1572, can be explained in the terms used nowadays to characterize Type Ia supernovae (SNe Ia). By assembling the records of the observations made in 1572–74 and evaluating their uncertainties, it is possible to recover the light curve and the color evolution…
Miras as a distance indicator in the CSST, JWST, and Gaia era
Sun, Yan; Zhang, Bo; Chen, Wen +5 more
Mira variables are important distance indicators owing to the clear period–luminosity relation at infrared wavelengths. We have compiled a sample of 343 Galactic Miras selected from the American Association of Variable Star Observers database and Gaia Data Release 3. We used V-band observations from the American Association of Variable Star Observ…
The ability of CSST to determine the orbital solutions of SB1s
Wang, Xiaoli; Fu, Yanning; Chen, Yue +1 more
The single-lined spectroscopic binaries (SB1s) are composed of two components with large difference in masses and in physical properties. The orbital and physical parameters of a large number of such binary systems are unknown due to lack of necessary observations. Compared with SB2s, SB1s can provide much more stringent constraint to stellar evol…
Asteroid Photometric Phase Functions From Bayesian Lightcurve Inversion
Muinonen, Karri; Cellino, Alberto; Wang, Xiaobin +3 more
Photometry is an important tool for characterizing the physical properties of asteroids. An asteroid's photometric lightcurve and phase curve refer to the variation of the asteroid's disk-integrated brightness in time and in phase angle (the Sun-asteroid-observer angle), respectively. They depend on the asteroid's shape, rotation, and surface scat…