390 citations · 911 across the 14 of their papers we have counts for
7 papers · 1 filter
Binary parameters from astrometric and spectroscopic errors--candidate hierarchical triples and massive dark companions in Gaia DR3
Shion Andrew, Zephyr Penoyre, Vasily Belokurov +2
We show how astrometric and spectroscopic errors introduced by an unresolved binary system can be combined to give estimates of the binary period and mass ratio. This can be perfor…
Kinematic modelling of clusters with Gaia: the Death Throes of the Hyades
Semyeong Oh, N. Wyn Evans
The precision of the Gaia data offers a unique opportunity to study the internal velocity field of star clusters. We develop and validate a forward-modelling method for the interna…
Unresolved stellar companions with Gaia DR2 astrometry
Vasily Belokurov, Zephyr Penoyre, Semyeong Oh +9
For stars with unresolved companions, motions of the centre of light and that of mass decouple, causing a single-source astrometric model to perform poorly. We show that such stars…
LRP2020: The Opportunity of Young Nearby Associations with the Advent of the Gaia Mission
Jonathan Gagné, Joel Kastner, Semyeong Oh +12
This white paper proposes leveraging high-quality Gaia data available to the worldwide scientific community and complement it with support from Canadian-related facilities to place…
Kronos & Krios: Evidence for accretion of a massive, rocky planetary system in a comoving pair of solar-type stars
Semyeong Oh, Adrian M. Price-Whelan, John M. Brewer +3
We report and discuss the discovery of a comoving pair of bright solar-type stars, HD 240430 and HD 240429, with a significant difference in their chemical abundances. The two star…
Spectroscopic confirmation of very-wide stellar binaries and large-separation comoving pairs from Gaia DR1
Adrian M. Price-Whelan, Semyeong Oh, David N. Spergel
Members of widely-separated stellar binaries (> 0.1 pc) or loosely bound stellar associations and clusters are born with small spreads in kinematics and chemistry, but disrupt and…
Comoving stars in Gaia DR1: An abundance of very wide separation co-moving pairs
Semyeong Oh, Adrian M. Price-Whelan, David W. Hogg +2
The primary sample of the {\it Gaia} Data Release 1 is the Tycho-Gaia Astrometric Solution (TGAS): 2 million Tycho-2 sources with improved parallaxes and proper motions r…