Publications (72)
Search for Past Stellar Encounters and the Origin of 3I/ATLAS
Yiyang Guo, Luyao Zhang, Fabo Feng +3
3I/ATLAS, the third discovered interstellar object, has a heliocentric speed of 58 km/s and exhibits cometary activity. To constrain the origin of 3I/ATLAS and its past dynamical e…
A Population Synthesis Study on the Formation of Cold Jupiters from Truncated Planetesimal Disks
Kangrou Guo, Masahiro Ogihara, Shigeru Ida +3
The occurrence rate of giant planets increases with orbital period and turns over at a location that roughly corresponds to the snow line of solar-type stars. Further, the density…
Evidence for at least three planet candidates orbiting HD20794
Fabo Feng, Mikko Tuomi, Hugh R. A. Jones
We explore the feasibility of detecting Earth analogs around Sun-like stars using the radial velocity method by investigating one of the largest radial velocities datasets for the…
Finding the imprints of stellar encounters in long period comets
Fabo Feng, C. A. L. Bailer-Jones
The solar system's Oort cloud can be perturbed by the Galactic tide and by individual passing stars. These perturbations can inject Oort cloud objects into the inner parts of the s…
A collage of small planets from the Lick Carnegie Exoplanet Survey : Exploring the super-Earth and sub-Neptune mass regime
Jennifer A. Burt, Fabo Feng, Bradford Holden +12
Analysis of new precision radial velocity (RV) measurements from the Lick Automated Planet Finder (APF) and Keck HIRES have yielded the discovery of three new exoplanet candidates…
Detection of the nearest Jupiter analog in radial velocity and astrometry data
Fabo Feng, Guillem Anglada-Escudé, Mikko Tuomi +4
The presence of Jupiter is crucial to the architecture of the Solar System and models underline this to be a generic feature of planetary systems. We find the detection of the diff…
A Goldilocks principle for modeling radial velocity noise
Fabo Feng, M. Tuomi, H. R. A. Jones +2
The doppler measurements of stars are diluted and distorted by stellar activity noise. Different choices of noise models and statistical methods have led to much controversy in the…
Detection of the closest Jovian exoplanet in the Epsilon Indi triple system
Fabo Feng, Mikko Tuomi, Hugh R. A. Jones
We confirm the trend in the radial velocity data for Epsilon Indi A suggesting a long-period planetary companion and find significant curvature is present, sufficient to quantify E…
Detection of four cold Jupiters through combined analyses of radial velocity and astrometry data
Yiyun Wu, Guang-Yao Xiao, R. Paul Butler +19
Cold Jupiters play a crucial role in planet formation and dynamical evolution. Since their initial discovery around 47 UMa, they have attracted significant interest, yet their form…
Activity and telluric contamination in HARPS observations of Alpha Centauri B
Maksym Lisogorskyi, Hugh Jones, Fabo Feng
The Alpha Centauri system is the primary target for planet search as it is the closest star system composed of a solar twin Alpha Centauri A, a K-dwarf Alpha Centauri B and an M-dw…
Mitigating astrometric bias in barycentric correction with PEXO
Yicheng Rui, Fabo Feng
Extremely precise radial velocity is essential for the detection of sub-m/s radial velocity of stars induced by Earth-like planets. Although modeling of the barycentric correction…
Exploring the robustness of Keplerian signals to the removal of active and telluric features
Maksym Lisogorskyi, Hugh R. A. Jones, Fabo Feng +2
We examine the influence of activity- and telluric-induced radial velocity signals on high resolution spectra taken with an iodine absorption cell. We exclude 2 Angstrom spectral c…
Forming Giant Planets Around Late-M Dwarfs: Pebble Accretion and Planet-Planet Collision
Mengrui Pan, Beibei Liu, Anders Johansen +6
We propose a pebble-driven core accretion scenario to explain the formation of giant planets around the late-M dwarfs of . In order to explore th…
The Magellan-TESS Survey I: Survey Description and Mid-Survey Results
Johanna Teske, Sharon Xuesong Wang, Angie Wolfgang +66
revealed that roughly one-third of Sun-like stars host planets orbiting within 100 days and between the size of Earth and Neptune. How do these planets form, what are they…
Minimizing the bias in exoplanet detection - application to radial velocities of LHS 1140
Fabo Feng, Mikko Tuomi, Hugh R. A. Jones
A rocky planet orbiting LHS 1140 with a period of 24.7d has been found based on the discovery of transits in its light and high precision radial velocity data (Dittmann et al. 2017…
Astrometric detection of exoplanets
Fabo Feng
As the most ancient branch of astronomy, astrometry has been developed for thousands of years. However, it has only recently become possible to utilize astrometry for the detection…
3-D selection of 167 sub-stellar companions to nearby stars
Fabo Feng, R. Paul Butler, Steven S. Vogt +20
We analyze 5108 AFGKM stars with at least five high precision radial velocity points as well as Gaia and Hipparcos astrometric data utilizing a novel pipeline developed in previous…
HD 222237 b: a long period super-Jupiter around a nearby star revealed by radial-velocity and Hipparcos-Gaia astrometry
Guang-Yao Xiao, Fabo Feng, Stephen A. Shectman +16
Giant planets on long period orbits around the nearest stars are among the easiest to directly image. Unfortunately these planets are difficult to fully constrain by indirect metho…
HiFLEx -- a highly flexible package to reduce cross-dispersed echelle spectra
Ronny Errmann, Neil Cook, Guillem Anglada-Escudé +8
We describe a flexible data reduction package for high resolution cross-dispersed echelle data. This open-source package is developed in Python and includes optional GUIs for most…
Updated Mutual Inclination Measurement for 14 Her b and c
Guang-Yao Xiao, Fabo Feng
The mutual inclination between orbits within multi-planetary systems is difficult to measure directly. Through a joint analysis of RVs, Hipparcos-Gaia absolute astrometry and…
HD 164604 c: a second giant planet on a 15-yr orbit and the constraint of the planet-planet mutual inclination
Guang-Yao Xiao, Fabo Feng, R. Paul Butler +4
We report the discovery of a new massive giant planet, HD 164604 c ( au, and or $7.6_{-1.0}…
Architecture of Tianyu Software: Relative Photometry as a Case Study
Yicheng Rui, Yifan Xuan, Shuyue Zheng +8
Tianyu telescope, an one-meter robotic optical survey instrument to be constructed in Lenghu, Qinghai, China, is designed for detecting transiting exoplanets, variable stars and tr…
The Jiao Tong University Spectroscopic Telescope Project
JUST Team, Chengze Liu, Ying Zu +28
The Jiao Tong University Spectroscopic Telescope (JUST) is a 4.4-meter f/6.0 segmentedmirror telescope dedicated to spectroscopic observations. The JUST primary mirror is composed…
A universal brown dwarf desert formed between planets and stars
Kaiming Cui, Guang-Yao Xiao, Fabo Feng +10
Giant planets and brown dwarfs play a crucial role in star and planet formation, as they are situated at the boundary between planets and stars with uncertain formation mechanisms.…
Detection of dark companions via the combination of eclipse timing variation, Hipparcos and/or Gaia astrometry: the cases of V Puppis and CY Ari
Guang-Yao Xiao, Fabo Feng, Song Wang +3
The third body is expected to shape the formation and evolution of close binary systems. In this work, we develop a method to detect and characterize the tertiary companion around…
LenghuSky-8: An 8-Year All-Sky Cloud Dataset with Star-Aware Masks and Alt-Az Calibration for Segmentation and Nowcasting
Yicheng Rui, Xiao-Wei Duan, Licai Deng +9
Ground-based time-domain observatories require minute-by-minute, site-scale awareness of cloud cover, yet existing all-sky datasets are short, daylight-biased, or lack astrometric…
Probabilistic galactic dynamics I - the Sun and GJ 710 with Monte Carlo, linearised and unscented treatments
Fabo Feng, Hugh R. A. Jones
Deterministic galactic dynamics is impossible due to the space-time randomness caused by gravitational waves. Instead of treating stellar orbits deterministically, we integrate not…
The test case of HD26965: difficulties disentangling weak Doppler signals from stellar activity
MatÃas R. DÃaz, James S. Jenkins, Mikko Tuomi +9
We report the discovery of a radial velocity signal that can be interpreted as a planetary-mass candidate orbiting the K dwarf HD26965, with an orbital period of 42.3640.015 d…
PEXO: a global modeling framework for nanosecond timing, microsecond astrometry, and m/s radial velocities
Fabo Feng, Maksym Lisogorskyi, Hugh R. A. Jones +4
The ability to make independent detections of the signatures of exoplanets with complementary telescopes and instruments brings a new potential for robust identification of exoplan…
Predicting the detection yields of giant planets and brown dwarfs with CSST astrometry
Yifan Xuan, Fabo Feng, Zhensen Fu +3
Chinese Space Station Telescope (CSST), which will begin its scientific operations around 2027, is going to survey the sky area of the median-to-high Galactic latitude and median-t…
The multi-planet system TOI-421 -- A warm Neptune and a super puffy mini-Neptune transiting a G9 V star in a visual binary
Ilaria Carleo, Davide Gandolfi, Oscar Barragán +110
We report the discovery of a warm Neptune and a hot sub-Neptune transiting TOI-421 (BD-14 1137, TIC 94986319), a bright (V=9.9) G9 dwarf star in a visual binary system observed by…
Search for Nearby Earth Analogs. III. Detection of ten new planets, three planet candidates, and confirmation of three planets around eleven nearby M dwarfs
Fabo Feng, Stephen A. Shectman, Matthew S. Clement +10
Earth-sized planets in the habitable zones of M dwarfs are good candidates for the study of habitability and detection of biosignatures. To search for these planets, we analyze all…
Two Earth-size Planets and an Earth-size Candidate Transiting the Nearby Star HD 101581
Michelle Kunimoto, Zifan Lin, Sarah Millholland +43
We report the validation of multiple planets transiting the nearby ( pc) K5V dwarf HD 101581 (GJ 435, TOI-6276, TIC 397362481). The system consists of at least two Earth-…
Tianyu: search for the second solar system and explore the dynamic universe
Fabo Feng, Yicheng Rui, Zhimao Du +32
Giant planets like Jupiter and Saturn, play important roles in the formation and habitability of Earth-like planets. The detection of solar system analogs that have multiple cold g…
Identify Light-Curve Signals with Deep Learning Based Object Detection Algorithm. I. Transit Detection
Kaiming Cui, Junjie Liu, Fabo Feng +1
Deep learning techniques have been well explored in the transiting exoplanet field; however, previous work mainly focuses on classification and inspection. In this work, we develop…
Search for nearby Earth analogs I. 15 planet candidates found in PFS data
Fabo Feng, Jeffrey D. Crane, Sharon Xuesong Wang +6
The radial velocity method plays a major role in the discovery of nearby exoplanets. To efficiently find planet candidates from the data obtained in high precision radial velocity…
Breaking the Mass Inclination Degeneracy of Radial Velocity Measurements via Monitoring von Zeipel-Lidov-Kozai Cycles: Implications in the HD 41004 System
Zhizhen Qin, Shang-Fei Liu, Bo Ma +1
We investigate the dynamical stability of the S-type planet in the compact binary HD 41004. Using -body simulations, we find that the planet could be dynamically stable at a mut…
A Cartesian catalog of 30 million Gaia sources based on second-order and Monte Carlo error propagation
Luyao Zhang, Fabo Feng, Yicheng Rui +2
Accurate measurements of stellar positions and velocities are crucial for studying galactic and stellar dynamics. We aim to create a Cartesian catalog from Gaia DR3 to serve as a h…
Search for Nearby Earth Analogs. II. detection of five new planets, eight planet candidates, and confirmation of three planets around nine nearby M dwarfs
Fabo Feng, R. Paul Butler, Stephen A. Shectman +9
Zechmeister et al. (2009) surveyed 38 nearby M dwarfs from March 2000 to March 2007 with VLT2 and the UVES spectrometer. This data has recently been reanalyzed (Butler et al. 2019)…
Binary Star Evolution in Different Environments: Filamentary, Fractal, Halo and Tidal-tail Clusters
Xiaoying Pang, Yifan Wang, Shih-Yun Tang +7
Using membership of 85 open clusters from previous studies (Pang et al. 2021a,b, 2022b; Li et al. 2021) based on Gaia DR3 data, we identify binary candidates in the color-magnitude…
A catalogue of close encounter pairs
Fabo Feng, Hugh R. A. Jones, Tabassum S. Tanvir
We provide a catalogue of pairs of stars whose periapses are less than 1pc within the past or future 100 Myr. We use astrometric data from TGAS, Hipparcos and radial velocity data…
Identifying Light-curve Signals with a Deep Learning Based Object Detection Algorithm. II. A General Light Curve Classification Framework
Kaiming Cui, D. J. Armstrong, Fabo Feng
Vast amounts of astronomical photometric data are generated from various projects, requiring significant effort to identify variable stars and other object classes. In light of thi…
Was Proxima captured by alpha Centauri A and B?
Fabo Feng, Hugh R. A. Jones
The nearest stellar system consists of the stars Proxima, alpha Centauri A and B and at least one planet Proxima b. The habitability of Proxima b and any other planets are likely t…
Unraveling the Complexity of Dwarf Galaxy Dynamics: A study of Binary Orbital Motions
Wenting Wang, Ling Zhu, Yipeng Jing +8
We investigate the impact of binary orbital motions on the dynamical modeling of dwarf galaxies with intrinsic line-of-sight velocity dispersions () of 1 to 9 km/s. Using…
Optimized modeling of Gaia-Hipparcos astrometry for the detection of the smallest cold Jupiter and confirmation of seven low mass companions
Fabo Feng, R. Paul Butler, Hugh R. A. Jones +6
To fully constrain the orbits of low mass circumstellar companions, we conduct combined analyses of the radial velocity data as well as the Gaia and Hipparcos astrometric data for…
Obliquity and precession as pacemakers of Pleistocene deglaciations
Fabo Feng, C. A. L. Bailer-Jones
The Milankovitch theory states that the orbital eccentricity, precession, and obliquity of the Earth influence our climate by modulating the summer insolation at high latitudes in…
The NCORES Program: Precise planetary masses, null results, and insight into the planet mass distribution near the radius gap
David J. Armstrong, Ares Osborn, Remo Burn +39
NCORES was a large observing program on the ESO HARPS spectrograph, dedicated to measuring the masses of Neptune-like and smaller transiting planets discovered by the TESS satellit…
Revisiting the HD 21749 Planetary System with Stellar Activity Modeling
Tianjun Gan, Sharon Xuesong Wang, Johanna K. Teske +26
HD 21749 is a bright ( mag) K dwarf at 16 pc known to host an inner terrestrial planet HD 21749c as well as an outer sub-Neptune HD 21749b, both delivered by TESS. Follow-up…
Observatory Science with eXTP
Ping Zhou, Jirong Mao, Liang Zhang +97
Scheduled for launch in 2030, the enhanced X-ray Timing and Polarization (eXTP) telescope is a Chinese space-based mission aimed at studying extreme conditions and phenomena in ast…
Revised orbits of the two nearest Jupiters
Fabo Feng, R. Paul Butler, Steven S. Vogt +2
With its near-to-mid-infrared high contrast imaging capabilities, JWST is ushering us into a golden age of directly imaging Jupiter-like planets. As the two closest cold Jupiters,…
A second visit to Eps Ind Ab with JWST: new photometry confirms ammonia and suggests thick clouds in the exoplanet atmosphere of the closest super-Jupiter
Elisabeth C. Matthews, James Mang, Aarynn L. Carter +9
With JWST, we are directly imaging cold (~200-300K), solar-age giant exoplanets for the first time. At these temperatures many molecular features appear and water-ice clouds may co…
Segmented-Polynomial-fitting Least Squares (SPLS): An optimized algorithm to find Earth twins
Shuyue Zheng, Fabo Feng, Yicheng Rui
Detecting Earth twins remains challenging because their shallow, long-period transits are difficult to distinguish from background noise. Motivated by the challenge, we developed S…
An improved quantification of HD 147379 b
Fabo Feng, Hugh R. A. Jones, Mikko Tuomi
We reanalyze the CARMENES and HIRES/KECK radial velocity data for HD 147379, and also analyze the SOPHIE data using the Agatha software in combination with MCMC posterior sampling.…
Doppler Constraints on Planetary Companions to Nearby Sun-like Stars: An Archival Radial Velocity Survey of Southern Targets for Proposed NASA Direct Imaging Missions
Katherine Laliotis, Jennifer A. Burt, Eric E. Mamajek +22
Directly imaging temperate rocky planets orbiting nearby, Sun-like stars with a 6-m-class IR/O/UV space telescope, recently dubbed the Habitable Worlds Observatory, is a high prior…
The Magellan/PFS Exoplanet Search: A 55-day period dense Neptune transiting the bright () star HD 95338
MatÃas R. DÃaz, James S. Jenkins, Fabo Feng +14
We report the detection of a transiting, dense Neptune planet candidate orbiting the bright () K0.5V star HD 95338. Detection of the 55-day periodic signal comes from the an…
The 3D Architecture of a pair of 6:1 Resonant Brown Dwarfs around the Naked-eye star Ophiuchi
Tianshenhong Sang, Guang-Yao Xiao, Ying-Yi Cao +8
We present a revisiting study of the brown dwarf pair orbiting the naked-eye () K-giant ~Ophiuchi, located only 44\,pc from our Solar system. By jointly analysing archiv…
Modeling and Calibration of Gaia, Hipparcos, and Tycho-2 astrometric data for the detection of dark companions
Fabo Feng, Yicheng Rui, Yifan Xuan +1
Hidden within the Gaia satellite's multiple data releases lies a valuable cache of dark companions. To facilitate the efficient and reliable detection of these companions via combi…
Cold giant discoveries from a joint radial-velocity and astrometry framework
Pablo A. Peña, James S. Jenkins, Fabo Feng +11
The population of long-period giant planets shapes planetary system architectures and formation pathways, but these cold Jupiters remain relatively unexplored. Radial velocity (RV)…
TOI-824 b: A New Planet on the Lower Edge of the Hot Neptune Desert
Jennifer A. Burt, Louise D. Nielsen, Samuel N. Quinn +54
We report the detection of a transiting hot Neptune exoplanet orbiting TOI-824 (SCR J1448-5735), a nearby (d = 64 pc) K4V star, using data from the \textit{Transiting Exoplanet Sur…
Color difference makes a difference: four planet candidates around tau Ceti
Fabo Feng, Mikko Tuomi, Hugh R. A. Jones +4
The removal of noise typically correlated in time and wavelength is one of the main challenges for using the radial velocity method to detect Earth analogues. We analyze radial vel…
Constraints on the nearby exoplanet Ind Ab from deep near/mid-infrared imaging limits
Gayathri Viswanath, Markus Janson, Carl-Henrik Dahlqvist +16
The past decade has seen increasing efforts in detecting and characterising exoplanets by high contrast imaging in the near/mid-infrared, which is the optimal wavelength domain for…
Exploring the role of the Sun's motion in terrestrial comet impacts
Fabo Feng, C. A. L. Bailer-Jones
The cratering record on the Earth and Moon shows that our planet has been exposed to high velocity impacts for much or all of its existence. Some of these craters were produced by…
Investigations into the impact of astronomical phenomena on the terrestrial biosphere and climate
Fabo Feng
This thesis assesses the influence of astronomical phenomena on the Earth's biosphere and climate. I examine in particular the relevance of both the path of the Sun through the Gal…
ET White Paper: To Find the First Earth 2.0
Jian Ge, Hui Zhang, Weicheng Zang +163
We propose to develop a wide-field and ultra-high-precision photometric survey mission, temporarily named "Earth 2.0 (ET)". This mission is designed to measure, for the first time,…
AstroSkyFlow: an astronomical sky image flow simulator for time domain survey validation and machine learning
Kexin Li, Yicheng Rui, Fabo Feng +5
Modern time-domain optical surveys produce massive data volumes that require robust, high-fidelity simulated datasets for developing and validating automated pipelines and machine-…
RVTESS I: Modeling Asteroseismic Signals with Simultaneous Photometry and RVs
Jiaxin Tang, Sharon X. Wang, Yaguang Li +22
Detecting small planets via the radial velocity method remains challenged by signals induced by stellar variability, versus the effects of the planet(s). Here, we explore using Gau…
Lessons learned from the detection of wide companions by radial velocity and astrometry
Fabo Feng, Guang-Yao Xiao, Hugh R. A. Jones +3
The detection and constraint of the orbits of long-period giant planets is essential for enabling their further study through direct imaging. Recently, it has been highlighted that…
TOI-1231 b: A Temperate, Neptune-Sized Planet Transiting the Nearby M3 Dwarf NLTT 24399
Jennifer A. Burt, Diana Dragomir, Paul Mollière +59
We report the discovery of a transiting, temperate, Neptune-sized exoplanet orbiting the nearby ( = 27.5 pc), M3V star TOI-1231 (NLTT 24399, L 248-27, 2MASS J10265947-5228099).…
Agatha: disentangling periodic signals from correlated noise in a periodogram framework
Fabo Feng, Mikko Tuomi, Hugh R. A. Jones
Periodograms are used as a key significance assessment and visualisation tool to display the significant periodicities in unevenly sampled time series. We introduce a framework of…
TESS Reveals a Short-period Sub-Neptune Sibling (HD 86226c) to a Known Long-period Giant Planet
Johanna Teske, MatÃas R. DÃaz, Rafael Luque +44
The Transiting Exoplanet Survey Satellite mission was designed to find transiting planets around bright, nearby stars. Here we present the detection and mass measurement of a small…
`Oumuamua as a messenger from the Local Association
Fabo Feng, Hugh R. A. Jones
With a hyperbolic trajectory around the Sun, `Oumuamua is the first confirmed interstellar object. However, its origin is poorly known. By simulating the orbits of 0.23 million loc…
Understanding Fomalhaut as a Cooper pair
Fabo Feng, Hugh R. A. Jones
Fomalhaut is a nearby stellar system and has been found to be a triple based on astrometric observations. With new radial velocity and astrometric data, we study the association be…