A5070721975- Astrophysics and Star Formation Studies
- Stellar, planetary, and galactic studies
- Astro and Planetary Science
- Molecular Spectroscopy and Structure
- Atmospheric Ozone and Climate
- Astronomy and Astrophysical Research
- Spacecraft and Cryogenic Technologies
- Astrophysical Phenomena and Observations
- Adaptive optics and wavefront sensing
- Spectroscopy and Laser Applications
- Thermodynamic properties of mixtures
- Phase Equilibria and Thermodynamics
- Planetary Science and Exploration
- Advanced Chemical Physics Studies
- Radio Astronomy Observations and Technology
- Astrophysics and Cosmic Phenomena
- Gamma-ray bursts and supernovae
- Astronomical Observations and Instrumentation
- Space Exploration and Technology
- Superconducting and THz Device Technology
- Advanced Thermodynamic Systems and Engines
- Electromagnetic Launch and Propulsion Technology
- Advanced Materials and Mechanics
- Galaxies: Formation, Evolution, Phenomena
- Venous Thromboembolism Diagnosis and Management
Boditech Med (South Korea)
2025
Carnegie Institution for Science
2017-2024
University of Florida
2021-2024
University of Ulsan
2022-2023
Asan Medical Center
2022-2023
Ulsan College
2022-2023
University of Michigan
2013-2020
Yonsei University
2011-2018
Carnegie Observatories
2018
Korea Astronomy and Space Science Institute
2009-2014
Planets form and obtain their compositions in dust gas-rich disks around young stars, the outcome of this process is intimately linked to disk chemical properties. The distributions molecules across regulate elemental planets, including C/N/O/S ratios metallicity (O/H C/H), as well access water prebiotically relevant organics. Emission from also encodes information on ionization levels, temperature structures, kinematics, gas surface densities, which are all key ingredients evolution planet...
Here we present high resolution (15-24 au) observations of CO isotopologue lines from the Molecules with ALMA on Planet-forming Scales (MAPS) Large Program. Our analysis employs $^{13}$CO and C$^{18}$O ($J$=2-1), (1-0), C$^{17}$O (1-0) line five protoplanetary disks. We retrieve gas density distributions, using three independent methods: (1) a thermo-chemical modeling framework based data, broadband spectral energy distribution, mm-continuum emission; (2) an empirical temperature...
Abstract Vertical shear instability (VSI), driven by a vertical gradient of rotational angular velocity, is promising source turbulence in protoplanetary disks. We examine the semiglobal stability thermally stratified disks and find that VSI consists surface body modes: modes are confined to regions strong shear, while extend perturbations across disk, consistent with previous findings. In disks, bifurcate into two branches. The branch associated strongest at mid-height exhibits higher...
As spiral waves driven by a planet in gaseous disk steepen into shock, they deposit angular momentum, opening gap the disk. This has been well studied using both linear theory and numerical simulations, but so far, only for primary arm -- one directly attached to planet. Using two-dimensional hydrodynamic we show that secondary tertiary arms can also open gaps as shocks. The depths of secondary/tertiary surface density grow with time low viscosity ($\alpha = 5\times10^{-5}$), even low-mass...
We present the first kinematical detection of embedded protoplanets within a protoplanetary disk. Using archival ALMA observations HD 163296, we demonstrate new technique to measure rotation curves CO isotopologue emission sub-percent precision relative Keplerian rotation. These betray substantial deviations caused by local perturbations in radial pressure gradient, likely driven gaps carved gas surface density Jupiter-mass planets. Comparison with hydrodynamic simulations shows excellent...
We improve on our previous treatments of the long-term evolution protostellar disks by explicitly solving disk self-gravity in two dimensions. The current model is an extension one-dimensional layered accretion Bae et al. find that gravitational instability (GI)-induced spiral density waves heat via compressional heating (i.e., PdV work), and can trigger outbursts activating magnetorotational (MRI) magnetically inert dead zone. GI-induced propagate well inside gravitationally unstable region...
Abstract The Molecules with ALMA at Planet-forming Scales Large Program (MAPS LP) surveyed the chemical structures of five protoplanetary disks across more than 40 different spectral lines high angular resolution (0.″15 and 0.″30 beams for Bands 6 3, respectively) sensitivity (spanning 0.3–1.3 mJy beam −1 0.4–1.9 respectively). In this article, we describe multistage workflow—built around CASA tclean image deconvolution procedure—that used to generate core data product MAPS LP:...
The Molecules with ALMA at Planet-forming Scales (MAPS) Large Program provides a unique opportunity to study the vertical distribution of gas, chemistry, and temperature in protoplanetary disks around IM Lup, GM Aur, AS 209, HD 163296, MWC 480. By using asymmetry molecular line emission relative disk major axis, we infer height ($z$) above midplane as function radius ($r$). Using this method, measure emitting surfaces for suite CO isotopologues, HCN, C$_2$H. We find that $^{12}$CO traces...
Young stars are surrounded by a circumstellar disk of gas and dust, within which planet formation can occur. Gravitational forces in multiple star systems disrupt the disk. Theoretical models predict that if is misaligned with orbital plane stars, should warp break into precessing rings, phenomenon known as tearing. We present observations triple system GWOrionis, finding evidence for Our images show an eccentric ring planes outer The casts shadows on strongly warped intermediate region If...
The Molecules with ALMA at Planet-forming Scales (MAPS) Large Program provides a detailed, high resolution (${\sim}$10-20 au) view of molecular line emission in five protoplanetary disks spatial scales relevant for planet formation. Here, we present systematic analysis chemical substructures 18 lines toward the MAPS sources: IM Lup, GM Aur, AS 209, HD 163296, and MWC 480. We identify more than 200 substructures, which are found nearly all radii where is detected. A wide diversity radial...
Constraining dust properties of planet-forming disks via high angular resolution observations is fundamental to understanding how solids are trapped in substructures and growth may be favored or accelerated therein. We use ALMA continuum the Molecules with at Planet-forming Scales (MAPS) explore a large parameter space constrain radial distribution solid mass maximum grain size each disk, including excluding scattering. In nonscattering model, surface density profiles decrease from inner...
Abstract While numerical simulations have been playing a key role in the studies of planet–disk interaction, testing results against observations has limited so far. With two directly imaged protoplanets embedded its circumstellar disk, PDS 70 offers an ideal testbed for interaction studies. Using two-dimensional hydrodynamic we show that observed features can be well explained with planets formation, providing strong evidence previously proposed theories are action, including resonant...
Abstract We explore the dynamical structure of protoplanetary disks surrounding HD 163296 and MWC 480 as part Molecules with ALMA at Planet-forming Scales (MAPS) large program. Using J = 2–1 transitions 12 CO, 13 C 18 O imaged spatial resolutions ∼0.″15 a channel spacing 200 m s −1 , we find perturbations from Keplerian rotation in projected velocity fields both (≲5% local velocity), suggestive large-scale (tens astronomical units size), coherent flows. By accounting for azimuthal dependence...
Abstract Gas-rich circumstellar disks are the cradles of planet formation. As such, their evolution will strongly influence resulting population. In ESO DESTINYS large program, we study these within first 10 Myr development with near-infrared scattered-light imaging. Here present VLT/SPHERE polarimetric observations nearby class II system SU Aur in which resolve disk down to scales ∼7 au. addition new SPHERE observations, utilize VLT/NACO, HST/STIS, and ALMA archival data. The data show...
The filamentary nature of accretion streams found around embedded sources suggest that protostellar disks experience heterogenous infall from the star-forming environment, consistent with behavior onto cores in top-down star-cluster formation simulations. This may produce disk substructures form rings, gaps, and spirals continuing to be identified by high-resolution imaging surveys both Class 0/I later II sources. We present a parameter study anisotropic infall, informed properties flows...
Abstract We report the discovery of a circumplanetary disk (CPD) candidate embedded in circumstellar T Tauri star AS 209 at radial distance about 200 au (on-sky separation 1.″4 from position angle 161°), isolated via 13 CO J = 2−1 emission. This is first instance CPD detection gaseous emission capable tracing overall mass. The spatially unresolved with 117 × 82 mas beam and manifests as point source CO, indicating that its diameter ≲14 au. within an annular gap previously identified using 12...
The sample of planet-forming disks observed by high-contrast imaging campaigns over the last decade is mature enough to enable demographical analysis individual star-forming regions. We present full census Taurus sources with VLT/SPHERE polarimetric images available. whole sums up 43 targets (of which 31 have not been previously published) corresponding one-fifth Class II population in and about half such objects that are observable. A large fraction apparently made isolated faint (equally...
Abstract We present MIRI Medium-resolution Spectrograph observations of the large, multi-gapped protoplanetary disk around T Tauri star AS 209. The reveal hundreds water vapor lines from 4.9–25.5 μ m toward inner ∼1 au in disk, including first detection rovibrational emission this disk. spectrum is dominated by hot (∼800 K) and OH gas, with only marginal detections CO 2 , HCN, a possible colder component. Using slab models detailed treatment opacities line overlap, we retrieve column...
Abstract PDS 70 hosts two massive, still-accreting planets and the inclined orientation of its protoplanetary disk presents a unique opportunity to directly probe vertical gas structure planet-hosting disk. Here, we use high-spatial-resolution (≈0.″1; 10 au) observations in set CO isotopologue lines HCO + J = 4−3 map full 2D ( r , z ) from atmosphere, as traced by 12 CO, closer midplane, probed less abundant isotopologues . In disk, traces height / ≈ 0.3, 13 is found at 0.1, C 18 O...
Abstract We conduct 3D hydrodynamic simulations to investigate the nonlinear outcomes and observability of vertical shear instability (VSI) in protoplanetary disks. Our models include both vertically isothermal thermally stratified disks, with latter representing realistic conditions featuring a hotter atmosphere above midplane. find that VSI grows more rapidly becomes stronger disks due enhanced shear, resulting higher levels turbulence. At saturation, turbulence stress reaches α Rϕ ≳ 10 −3...
Abstract Protoplanetary disk simulations show that a single planet can excite more than one spiral arm, possibly explaining the recent observations of multiple arms in some systems. In this paper, we explain mechanism by which excites protoplanetary disk. Contrary to previous speculations, formation both primary and additional be understood as linear process when mass is sufficiently small. A resonantly interacts with epicyclic oscillations disk, launching wave modes around Lindblad...
Context. PDS 70 is a young (5.4 Myr), nearby (~113 pc) star hosting known transition disk with large gap. Recent observations SPHERE and NACO in the near-infrared (NIR) allowed us to detect planetary mass companion, PDS70b, within cavity. Moreover, H_alpha MagAO MUSE revealed emission associated PDS70b another new companion candidate, PDS70c, at larger separation from star. Aims. Our aim confirm discovery of second planet PDS70c using VLT, further characterize its physical properties, search...
We present the discovery of a spatially unresolved source sub-millimeter continuum emission ($\lambda=855$ $\mu$m) associated with young planet, PDS 70 c, recently detected in H$\alpha$ around 5 Myr old T Tauri star 70. interpret as originating from dusty circumplanetary disk dust mass between $2\times10^{-3}$ and $4.2 \times 10^{-3}$ Earth masses. Assuming standard gas-to-dust ratio 100, total central planet would be $10^{-4}-10^{-5}$. Furthermore, we report another compact located...
Combining hydrodynamic planet-disk interaction simulations with dust evolution models, we show that protoplanetary disks having a giant planet can reveal diverse morphology in (sub-)millimeter continuum, including full disk without significant radial structure, transition an inner cavity, single gap and central continuum peak, multiple rings gaps. Such diversity originates from (1) the level of viscous transport which determines number gaps open; (2) size spatial distributions grains...