A5005856762- Stellar, planetary, and galactic studies
- Astro and Planetary Science
- Astrophysics and Star Formation Studies
- Astronomy and Astrophysical Research
- Gamma-ray bursts and supernovae
- Quantum chaos and dynamical systems
- Adaptive optics and wavefront sensing
- Planetary Science and Exploration
- Astronomical and nuclear sciences
- Nuclear physics research studies
- Astronomical Observations and Instrumentation
- Scientific Research and Discoveries
- Geomagnetism and Paleomagnetism Studies
- Nonlinear Dynamics and Pattern Formation
- Astrophysical Phenomena and Observations
- Hydrocarbon exploration and reservoir analysis
- Mathematical Dynamics and Fractals
- Theoretical and Computational Physics
- Pulsars and Gravitational Waves Research
- High-pressure geophysics and materials
- Quantum, superfluid, helium dynamics
- History and Developments in Astronomy
- Infrared Target Detection Methodologies
- Atomic and Molecular Physics
- Space Science and Extraterrestrial Life
Nanjing University
2016-2025
Astronomy and Space
2025
Ministry of Education of the People's Republic of China
2021-2024
Ocean University of China
2024
ORCID
2021
Purple Mountain Observatory
2007
Southeast University
2004
Nanjing Institute of Astronomical Optics & Technology
2002
Hong Kong Baptist University
1998-2000
We investigate the orbit-crossing time (T_c) of protoplanet systems both with and without a gas-disk background. The protoplanets are initially equal masses separation (EMS systems) scaled by their mutual Hill's radii. In gas-free environment, we find log (T_c/yr) = A+B \log (k_0/2.3). Through simple analytical approach, demonstrate that evolution velocity dispersion in an EMS system follows random walk. stochastic nature random-walk diffusion leads to (i) increasing average eccentricity ~...
Significance Hot Jupiters are Jupiter-size planets at £1/10 of the Sun–Earth distance, and even though they were first exoplanet population discovered around sun-like stars, their origins still remain elusive. Using data from NASA’s Kepler satellite China’s Large Sky Area Multi-Object Fiber Spectroscopic Telescope, we discover a close-in Neptune-size (called “Hoptunes”) that share key similarities with hot Jupiters. Like Jupiters, Hoptunes prefer to reside stars higher metal abundance than...
The solar and extrasolar gas giants appear to have diverse internal structure metallicities. We examine a potential cause for these dispersions in the context of conventional sequential accretion formation scenario. In principle, onto cores with masses below several times that Earth is suppressed by energy released from bombardment residual planetesimals. Due their aerodynamical tidal interaction nascent disk, planetesimals on eccentric orbits undergo slow orbital decay. show generally...
Stellar perturbations affect planet-formation in binary systems. Recent studies show that the stage of mutual accretion km-sized planetesimals is most sensitive to effects. In this paper, condition for planetesimal investigated around Alpha CenB, which believed be an ideal candidate detection Earth-like planet or near its habitable zone(0.5-0.9 AU). A simplified scaling method developed estimate timescale embedded a protoplanetary disk. Twenty-four cases with different inclinations(i_B=0,...
The radius valley, a dip in the distribution of exoplanets at ~1.9 Earth radii separates compact rocky Super-Earths and Sub-Neptunes with lower density. Various hypotheses have been put forward to explain valley. Characterizing valley morphology its correlation stellar properties will provide crucial observation constraints on origin mechanism deepen understanding planet formation evolution. In this paper, third part Planets Across Space Time (PAST) series, using LAMOST-Gaia-Kepler catalog,...
We present ten $R$-band photometric observations of eight different transits the hot Jupiter HAT-P-33b, which has been targeted by our Transiting Exoplanet Monitoring Project (TEMP). The data were obtained two telescopes at Xinglong Station National Astronomical Observatories China (NAOC) from 2013 December through 2016 January, and exhibit scatter $1.6-3.0\,\rm{mmag}$. After jointly analyzing previously published data, radial-velocity (RV) measurements, new light curves, we revisit system...
The unexpected discovery of hot Jupiters challenged the classical theory planet formation inspired by our solar system. Until now, origin and evolution are still uncertain. Determining their age distribution temporal can provide more clues into mechanism subsequent evolution. Using a sample 383 giant planets around Sun-like stars collected from kinematic catalogs Planets Across Space Time (PAST) project, we find that preferentially hosted relatively younger in Galactic thin disk. We...
We investigated the apsidal motion for multiplanet systems. In simulations, we found that two planets of HD 37124, 12661, 47 UMa, and 82943 separately undergo alignment or antialignment. However, companions GJ 876 υ And are in lock only about 0°. Moreover, obtained criteria with Laplace-Lagrange secular theory to discern whether a pair certain system libration circulation.
Currently, one of the major theoretical problems concerning planet formation in close binary systems is whether strong perturbation from companion star can increase relative velocities (ΔV) planetesimals around primary and thus hinder their growth. According to previous studies, while gas drag reduce ΔV between bodies same size by forcing orbital alignment on planetesimals, it increases among different sizes. In this paper, focusing γ Cephei system, we propose a mechanism that overcome...
The standard model of planet formation considers an initial phase in which planetesimals form from a dust disk, followed by mutual planetesimal–planetesimal collisions, leading eventually to the planetary embryos. However, there is potential transition (which we call "snowball phase"), between first and onset collisions amongst them, has often been either ignored or underestimated previous studies. In this snowball phase, isolated move Keplerian orbits grow solely via direct accretion...
Most detected planet-bearing binaries are in wide orbits, for which a high inclination, iB, between the binary orbital plane and of planetary disk around primary is likely to be common. In this paper, we investigate intermediate stages—from planetesimals embryos/cores—of planet formation such highly inclined cases. Our focus on effects gas drag planetesimals' evolution, particular evolution semimajor axis distribution their mutual relative velocities. We first demonstrate that non-evolving...
The Kepler-9 system harbors three known transiting planets. holds significant interest for several reasons. First, the outer two planets exhibit a period ratio that is close to 2:1 orbital commensurability, with attendant dynamical consequences. Second, both lie in planetary mass "desert" generally associated rapid gas agglomeration phase of core accretion process. Third, there exist attractive prospects accurately measuring sky-projected stellar spin-orbit angles as well mutual inclination...
We examine the effects that dynamical instability has on shaping orbital properties of exoplanetary systems. Using N-body simulations non-EMS (Equal Mutual Separation), multiplanet systems we find lower limit time-scale t is determined by minimal mutual separation Kmin in units Hill radius. Planetary showing generally include planet pairs with period ratio <1.33. Our final distribution all adjacent shows dip-peak structures near first-order mean motion resonances similar to those observed...
Abstract During the past five years, 6, 7, and 26 transit observations were carried out for HAT-P-9b, HAT-P-32b, HAT-P-36b systems, respectively, through Transiting Exoplanet Monitoring Project network. Combined with published photometric data radial-velocity measurements, our new photometry allows us to revisit system parameters search additional close-in planetary companions in these hot Jupiter systems. We measure an updated R P / * = 0.1260 ± 0.0011 HAT-P-36 band, which is 4.5 σ larger...
We present 127 new transit light curves for 39 hot Jupiter systems, obtained over the span of five years by two ground-based telescopes. A homogeneous analysis these newly collected together with archived spectroscopic, photometric, and Doppler velocimetric data using EXOFASTv2 leads to a significant improvement in physical orbital parameters each system. All our stellar radii are constrained accuracies better than 3\%. The planetary 37 targets determined $5\%$. Compared results, literature...
Abstract The habitability of planets is closely connected with stellar activity, mainly the frequency flares and distribution flare energy. Kepler TESS find many flaring stars via precise time-domain photometric data, energy on different types are studied statistically. However, completeness observational bias detected events from missions (e.g., TESS) vary a lot. We use unified data processing detection method for based light curves TESS. Then we perform injection recovery tests in original...
With the help of Laplace-Lagrange solution secular perturbation theory in a double-planet system, we study occurrence and stability apsidal resonance between two planets. The explicit criteria for predicting whether planets are is derived, which shows that depends only on mass ratio (m1/m2), semimajor axis (a1/a2), initial eccentricity (e10/e20), relative longitude (ϖ20 - ϖ10) probability falling given element space. We verify with numerical integrations HD 12661 system find they give good...
We carry out a series of high-resolution (1024 × 1024) hydrodynamic simulations to investigate the orbital evolution Saturn–Jupiter pair embedded in gaseous disk. This work extends results our previous by exploring different configuration—Jupiter lies outside Saturn (q < 1, where q ≡ Mi/Mo is mass ratio inner planet and outer one). focus on effects initial separations (d) between two planets various surface density profiles disk, σ ∝ r−α. also compare configurations pair. Our show that (1)...
We investigate the effects of gas–disk gravity on planetesimal dynamics in inclined binary systems, where circumprimary disk plane is tilted by a significant angle (iB) with respect to plane. Our focus Lidov–Kozai mechanism and evolution eccentricity inclination. Using both analytical numerical methods, we find that, one hand, generally narrows down Kozai-on region, i.e., effect can be suppressed certain parts (or even whole of) depending various parameters. In Kozai-off planetesimals would...
The recent Kepler discovery of KOI-152 reveals a system three hot super-Earth candidates that are in or near 4:2:1 mean motion resonance. It is unlikely they formed situ; the planets probably underwent orbital migration during formation and evolution process. small semimajor axes suggest stopped at inner edge primordial gas disk. In this paper, we focus on influence halting mechanisms, including "dead zones," truncation by stellar magnetic field. We show accretion rate, field, speed...
Compared to the giant planets in solar system, exoplanets have many remarkable properties such as prevalence of on eccentric orbits and presence hot Jupiters. Planet-planet scattering (PPS) between is a possible mechanism interpreting above other observed properties. If planet architectures are indeed outcomes PPS, drastic dynamical process must affect their primordial moon systems. In this Letter, we discuss effect PPS survival regular moons. From viewpoint observations, some preliminary...
Analysis of the transit timing variations (TTVs) candidate pairs near mean-motion resonances (MMRs) is an effective method to confirm planets. Hitherto, 68 planets in 34 multi-planet systems have been confirmed via TTVs. We analyze TTVs all candidates from most recent Kepler data with a time span as long about 1350 days (Q0-Q15). The anti-correlations TTV signals and mass upper limits same system are calculated, using improved suitable for long-period If false alarm probability (FAP) pair...
Accordling to the theory of Kozai resonance, initial mutual inclination between a small body and massive planet in an outer circular orbit is as high $\sim39.2^{\circ}$ for pumping eccentricity inner body. Here we show that, with presence residual gas disk outside two planetary orbits, can be reduced low few degrees. The changes nodal precession rates directions orbits. At place where planets achieve same processing rate, vertical secular resonance would occur so that will excited, which...
Abstract The Kepler telescope has discovered over 4000 planets (candidates) by searching ∼200,000 stars a wide range of distance (order kpc) in our Galaxy. Characterizing the kinematic properties (e.g., Galactic component membership and age) these targets (including planet candidate hosts) is first step toward studying context, which will reveal fresh insights into formation evolution. In this paper, second part Planets Across Space Time (PAST) series, combining data from Large Sky Area...