Publications (108)
Mapping Protoplanetary Disk Vertical Structure with CO Isotopologue Line Emission
Charles J. Law, Richard Teague, Karin I. Ãberg +21
High spatial resolution observations of CO isotopologue line emission in protoplanetary disks at mid-inclinations (30-75°) allow us to characterize the gas structure in…
The Structure of Pre-transitional Protoplanetary Disks I: Radiative Transfer Modeling of the Disk+Cavity in the PDS 70 system
Ruobing Dong, Jun Hashimoto, Roman Rafikov +49
Through detailed radiative transfer modeling, we present a disk+cavity model to simultaneously explain both the SED and Subaru H-band polarized light imaging for the pre-transition…
Near-Infrared Imaging Polarimetry of S106 Cluster-Forming Region with SIRPOL
Hiro Saito, Motohide Tamura, Ryo Kandori +7
We present the results of wide-field JHKs polarimetry toward the HII region S106 using the IRSF (Infrared Survey Facility) telescope. Our polarimetry data revealed an extended (up…
SUBARU Near-Infrared Imaging Polarimetry of Misaligned Disks Around The SR24 Hierarchical Triple System
Satoshi Mayama, Sebastián Pérez, Nobuhiko Kusakabe +65
The SR24 multi-star system hosts both circumprimary and circumsecondary disks, which are strongly misaligned from each other. The circumsecondary disk is circumbinary in nature. In…
Characterizing the Time Variability of 2M1207 A+b with JWST NIRSpec/PRISM
Arthur D. Adams, Yifan Zhou, Gabriel Dominique-Marleau +13
We present JWST NIRSpec/PRISM IFU time-resolved observations of 2M1207 A and b (TWA 27), a Myr binary system consisting of a K sub-stellar primary hosting a $…
VLT/MUSE Detection of the AB Aurigae b Protoplanet with Spectroscopy
Thayne Currie, Jun Hashimoto, Yuhiko Aoyama +6
We analyze high-contrast, medium-spectral-resolution observations of the star AB Aurigae using the Very Large Telescope's Multi Unit Spectroscopic Explorer (MUSE). In…
The Sizes and Depletions of the Dust and Gas Cavities in the Transitional Disk J160421.7-213028
Ruobing Dong, Nienke van der Marel, Jun Hashimoto +18
We report ALMA Cycle 2 observations of 230 GHz (1.3 mm) dust continuum emission, and CO, CO, and CO J = 2-1 line emission, from the Upper Scorpius transitional…
Testing magnetospheric accretion as an H emission mechanism of embedded giant planets: The case study for the disk exhibiting meridional flow around HD 163296
Yasuhiro Hasegawa, Taichi Uyama, Jun Hashimoto +7
Recent high-sensitivity observations reveal that accreting giant planets embedded in their parental circumstellar disks can emit H at their final formation stages. While the or…
Polarimetric Imaging of Large Cavity Structures in the Pre-transitional Protoplanetary Disk around PDS 70: Observations of the disk
Jun Hashimoto, Ruobing Dong, Tomoyuki Kudo +52
We present high resolution H-band polarized intensity (PI; FWHM = 0."1: 14 AU) and L'-band imaging data (FWHM = 0."11: 15 AU) of the circumstellar disk around the weak-lined T Taur…
A Spatially Resolved AU-scale Inner Disk around DM Tau
Tomoyuki Kudo, Jun Hashimoto, Takayuki Muto +5
We present Atacama Large Millimeter/submillimeter Array (ALMA) observations of the dust continuum emission at 1.3 mm and 12CO J=2-1 line emission of the transitional disk around DM…
JVLA Measurement of Grain Size in the Compact Dust Ring around Class I Protostar WL 17
Jun Hashimoto, Hauyu Baobab Liu, Ruobing Dong +2
The maximum grain size in protoplanetary disks is a critical parameter for planet formation, as the efficiency of mechanisms like streaming instability and pebble accretion depend…
Discovery of an au-scale excess in millimeter emission from the protoplanetary disk around TW Hya
Takashi Tsukagoshi, Takayuki Muto, Hideko Nomura +10
We report the detection of an excess in dust continuum emission at 233~GHz (1.3~mm in wavelength) in the protoplanetary disk around TW~Hya revealed through high-sensitivity observa…
Time-variable Scattered Light in Herbig Disks Observed with Subaru/SCExAO
Camryn Mullin, Miles Lucas, Ruobing Dong +12
Using the Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) instrument, we present near-infrared K-band polarimetric imaging of nine Herbig stars selected from a volume-limited…
Direct Imaging Search for Extrasolar Planets in the Pleiades
Kodai Yamamoto, Taro Matsuo, Hiroshi Shibai +53
We carried out an imaging survey for extrasolar planets around stars in the Pleiades (125 Myr, 135 pc) in the and bands using HiCIAO combined with the adaptive optics,…
Multiple Rings and Asymmetric Structures in the Disk of SR 21
Yi Yang, Hauyu Baobab Liu, Takayuki Muto +9
Crescent-like asymmetric dust structures discovered in protoplanetary disks indicate dust aggregations. Thus, the research on them helps us understand the planet formation process.…
An asymmetric dust ring around a very low mass star ZZ Tau IRS
Jun Hashimoto, Ruobing Dong, Takayuki Muto
We present Atacama Large Millimeter/submillimeter Array (ALMA) gas and dust observations at band 7 (339~GHz: 0.89~mm) of the protoplanetary disk around a very low mass star ZZ~Tau~…
GW Ori: Interactions Between a Triple-star System and its Circumtriple Disk in Action
Jiaqing Bi, Nienke van der Marel, Ruobing Dong +17
GW Ori is a hierarchical triple system which has a rare circumtriple disk. We present Atacama Large Millimeter/submillimeter Array (ALMA) observations of 1.3 mm dust continuum and…
Multi-epoch Direct Imaging and Time-Variable Scattered Light Morphology of the HD 163296 Protoplanetary Disk
Evan A. Rich, John P. Wisniewski, Thayne Currie +58
We present H-band polarized scattered light imagery and JHK high-contrast spectroscopy of the protoplanetary disk around HD 163296 observed with the HiCIAO and SCExAO/CHARIS instru…
A Discovery of a Candidate Companion to a Transiting System KOI-94: A Direct Imaging Study for a Possibility of a False Positive
Yasuhiro H. Takahashi, Norio Narita, Teruyuki Hirano +49
We report a discovery of a companion candidate around one of {\it Kepler} Objects of Interest (KOIs), KOI-94, and results of our quantitative investigation of the possibility that…
Circumstellar Disks of the Most Vigorously Accreting Young Stars
Hauyu Baobab Liu, Michihiro Takami, Tomoyuki Kudo +11
Young stellar objects (YSOs) may not accumulate their mass steadily, as was previously thought, but in a series of violent events manifesting themselves as sharp stellar brightenin…
Radial decoupling of small and large dust grains in the transitional disk RX J1615.3-3255
Robin Kooistra, Inga Kamp, Misato Fukagawa +56
We present H-band (1.6 μm) scattered light observations of the transitional disk RX J1615.3-3255, located in the ~1 Myr old Lupus association. From a polarized intensity image, ta…
Probing Signatures of a Distant Planet around the Young T-Tauri Star CI Tau Hosting a Possible Hot Jupiter
Mihoko Konishi, Jun Hashimoto, Yasunori Hori
We search for signatures of a distant planet around the two-million-year-old classical T-Tauri star CI Tau hosting a hot Jupiter candidate (M_{p} sin{i} ~ 8.1 M_{Jupiter}) in an ec…
A likely flyby of binary protostar Z CMa caught in action
Ruobing Dong, Hauyu Baobab Liu, Nicolas Cuello +16
Close encounters between young stellar objects in star forming clusters are expected to dramatically perturb circumstellar disks. Such events are witnessed in numerical simulations…
Mapping H-band Scattered Light Emission in the Mysterious SR21 Transitional Disk
Katherine B. Follette, Motohide Tamura, Jun Hashimoto +50
We present the first near infrared (NIR) spatially resolved images of the circumstellar transitional disk around SR21. These images were obtained with the Subaru HiCIAO camera, ada…
Search for Outer Massive Bodies around Transiting Planetary Systems: Candidates of Faint Stellar Companions around HAT-P-7
Norio Narita, Tomoyuki Kudo, Carolina Bergfors +46
We present results of direct imaging observations for HAT-P-7 taken with the Subaru HiCIAO and the Calar Alto AstraLux. Since the close-in transiting planet HAT-P-7b was reported t…
High-contrast H imaging with Subaru/SCExAO+VAMPIRES
Taichi Uyama, Barnaby Norris, Nemanja Jovanovic +7
We present current status of H high-contrast imaging observations with Subaru/SCExAO+VAMPIRES. Our adaptive optics correction at optical wavelengths in combination with (double…
Thermal Infrared Imaging and Atmospheric Modeling of VHS J125601.92-125723.9 b: Evidence for Moderately Thick Clouds and Equilibrium Carbon Chemistry in a Hierarchical Triple System
Evan A. Rich, Thayne Currie, John P. Wisniewski +5
We present and analyze Subaru/IRCS L' and M' images of the nearby M dwarf VHS J125601.92-125723.9 (VHS 1256), which was recently claimed to have a ~11 M_Jup companion (VHS 1256 b)…
SEEDS Adaptive Optics Imaging of the Asymmetric Transition Disk Oph IRS 48 in Scattered Light
Katherine B. Follette, Carol A. Grady, Jeremy R. Swearingen +60
We present the first resolved near infrared imagery of the transition disk Oph IRS 48 (WLY 2-48), which was recently observed with ALMA to have a strongly asymmetric sub-millimeter…
ALMA Observations of the Asymmetric Dust Disk around DM Tau
Jun Hashimoto, Takayuki Muto, Ruobing Dong +5
We report an analysis of the dust disk around DM~Tau, newly observed with the Atacama Large Millimeter/submillimeter Array (ALMA) at 1.3 mm. The ALMA observations with high sensiti…
An Observational Perspective of Transitional Disks
Catherine Espaillat, James Muzerolle, Joan Najita +7
Transitional disks are objects whose inner disk regions have undergone substantial clearing. The Spitzer Space Telescope produced detailed spectral energy distributions (SEDs) of t…
Near-IR Polarized Scattered Light Imagery of the DoAr 28 Transitional Disk
Evan A. Rich, John P. Wisniewski, Satoshi Mayama +52
We present the first spatially resolved polarized scattered light H-band detection of the DoAr 28 transitional disk. Our two epochs of imagery detect the scattered light disk from…
Surface Geometry of Protoplanetary Disks Inferred From Near-Infrared Imaging Polarimetry
Michihiro Takami, Yasuhiro Hasegawa, Takayuki Muto +58
We present a new method of analysis for determining the surface geometry of five protoplanetary disks observed with near-infrared imaging polarimetry using Subaru-HiCIAO. Using as…
The detection of dust gap-ring structure in the outer region of the CR Cha protoplanetary disk
Seongjoong Kim, Sanemichi Takahashi, Hideko Nomura +13
We observe the dust continuum at 225 GHz and CO isotopologue (12CO, 13CO, and C18O) J=2-1 emission lines toward the CR Cha protoplanetary disk using the Atacama Large Millimeter/Su…
Shadowing in the protoplanetary disk of ZZ Tau IRS with HST
Jun Hashimoto, Ruobing Dong, Takayuki Muto +2
An inner component misaligned from an outer component in a protoplanetary disk can result in the former casting shadows on the latter. We present a new instance of shadowing on the…
Near-Infrared Imaging Polarimetry of Inner Region of GG Tau A Disk
Yi Yang, Jun Hashimoto, Saeko S. Hayashi +51
By performing non-masked polarization imaging with Subaru/HiCIAO, polarized scattered light from the inner region of the disk around the GG Tau A system was successfully detected i…
Monitoring inner regions in the RY Tau jet
Taichi Uyama, Michihiro Takami, Gabriele Cugno +18
We present multi-epoch observations of the RY~Tau jet for H and [\ion{Fe}{2}] 1.644 \micron~emission lines obtained with Subaru/SCExAO+VAMPIRES, Gemini/NIFS, and Keck/OSIRIS in…
Sub-Arcsecond Near-Infrared Images of Massive Star Formation Region NGC 6334 V
Jun Hashimoto, Motohide Tamura, Hiroshi Suto +4
We present high spatial resolution (0$\farcs$3) polarimetric images in the and bands and direct images in the and bands of the NGC 6334 V infrared nebulae. The im…
Evidence for Variable Accretion onto PDS 70 c and Implications for Protoplanet Detections
Yifan Zhou, Brendan P. Bowler, Aniket Sanghi +14
Understanding the processes of planet formation and accretion in young systems is essential to unraveling the initial conditions of planetary systems. The PDS 70 system, which host…
Gravitational instability in a planet-forming disk
Jessica Speedie, Ruobing Dong, Cassandra Hall +7
The canonical theory for planet formation in circumstellar disks proposes that planets are grown from initially much smaller seeds. The long-considered alternative theory proposes…
Keck/OSIRIS Pa high-contrast imaging and updated constraints on PDS~70b
Taichi Uyama, Chen Xie, Yuhiko Aoyama +11
We present a high-contrast imaging search for Pa line emission from protoplanets in the PDS~70 system with Keck/OSIRIS integral field spectroscopy. We applied the high-resoluti…
Forming localized dust concentrations in a dust ring: DM Tau case study
Hauyu Baobab Liu, Takayuki Muto, Mihoko Konishi +8
The previous, high angular resolution 225 GHz (1.3 mm) continuum observations on the transitional disk DM Tau have resolved an outer ring at 20-120 au radii that is weakly az…
Images of Embedded Jovian Planet Formation At A Wide Separation Around AB Aurigae
Thayne Currie, Kellen Lawson, Glenn Schneider +30
Direct images of protoplanets embedded in disks around infant stars provide the key to understanding the formation of gas giant planets like Jupiter. Using the Subaru Telescope and…
A Possible Converter to Denoise the Images of Exoplanet Candidates through Machine Learning Techniques
Pattana Chintarungruangchai, Ing-Guey Jiang, Jun Hashimoto +2
The method of direct imaging has detected many exoplanets and made important contribution to the field of planet formation. The standard method employs angular differential imaging…
ALMA Observations of the Inner Cavity in the Protoplanetary Disk around Sz 84
Jun Hashimoto, Takayuki Muto, Ruobing Dong +5
We present Atacama Large Millimeter/submillimeter Array (ALMA) observations of a protoplanetary disk around the T Tauri star Sz~84 and analyses of the structures of the inner cavit…
Constraining the Movement of the Spiral Features and the Locations of Planetary Bodies within the AB Aur System
Jamie R. Lomax, John P. Wisniewski, Carol A. Grady +54
We present new analysis of multi-epoch, H-band, scattered light images of the AB Aur system. We used a Monte Carlo, radiative transfer code to simultaneously model the system's SED…
Revisiting the Helium and Hydrogen Accretion Indicators at TWA 27B: Weak Mass Flow at Near-Freefall Velocity
Gabriel-Dominique Marleau, Yuhiko Aoyama, Jun Hashimoto +1
TWA 27B (2M1207b) is the first directly-imaged planetary-mass (MP ~ 5 MJ) companion (Chauvin et al. 2004) and was observed at 0.9--5.3 micron with JWST/NIRSpec (Luhman et al. 2023)…
First JVLA Radio Observation on PDS70
Hauyu Baobab Liu, Simon Casassus, Ruobing Dong +3
PDS~70 is a protoplanetary system that hosts two actively accreting gas giants, namely PDS~70b and PDS~70c. The system has a 60--100 au dusty ring that has been resolved by A…
Early High-contrast Imaging Results with Keck/NIRC2-PWFS: The SR 21 Disk
Taichi Uyama, Bin Ren, Dimitri Mawet +22
High-contrast imaging of exoplanets and protoplanetary disks depends on wavefront sensing and correction made by adaptive optics instruments. Classically, wavefront sensing has bee…
Near-Infrared Imaging Polarimetry of the NGC 2071 Star Forming Region with SIRPOL
Motohide Tamura, Ryo Kandori, Jun Hashimoto +10
We have conducted deep JHKs imaging polarimetry of a ~8' x 8' area of the NGC 2071 star forming region. Our polarization data have revealed various infrared reflection nebulae (IRN…
Direct Imaging of Bridged Twin Protoplanetary Disks in a Young Multiple Star
Satoshi Mayama, Motohide Tamura, Tomoyuki Hanawa +10
Studies of the structure and evolution of protoplanetary disks are important for understanding star and planet formation. Here, we present the direct image of an interacting binary…
Near-Infrared Imaging Polarimetry of M42: Aperture Polarimetry of Point-like Sources
Nobuhiko Kusakabe, Motohide Tamura, Ryo Kandori +6
We have conducted aperture polarimetry of ~500 stars of the Orion Nebula Cluster (ONC) in M42 based on our wide-field (~8'\times 8') band polarimetry. Most of the near-infra…
Near-Infrared High-Resolution Imaging Polarimetry of FU Ori-Type Objects: Towards A Unified Scheme for Low-Mass Protostellar Evolution
Michihiro Takami, Guangwei Fu, Hauyu Baobab Liu +14
We present near-IR imaging polarimetry of five classical FU Ori-type objects (FU Ori, V1057 Cyg, V1515 Cyg, V1735 Cyg, Z CMa) with a 0\farcs1 resolution observed using HiCIAO…
Near-Infrared Polarimetry of the GG Tauri A Binary System
Yoichi Itoh, Yumiko Oasa, Tomoyuki Kudo +47
A high angular resolution near-infrared polarized-intensity image of the GG Tau A binary system was obtained with the Subaru Telescope. The image shows the circumbinary disk scatte…
Near Infrared Circular Polarization Images of NGC 6334-V
Jungmi Kwon, M. Tamura, P. Lucas +7
We present results from deep imaging linear and circular polarimetry of the massive star-forming region NGC 6334- V. These observations show high degrees of circular polarization (…
High-contrast Polarimetry Observation of T Tau Circumstellar Environment
Yi Yang, Satoshi Mayama, Saeko S. Hayashi +52
We conducted high-contrast polarimetry observations of T Tau in the H-band, using the HiCIAO instrument mounted on the Subaru Telescope, revealing structures as near as 0.$\arcsec$…
Near-Infrared Polarization Images of The Orion Molecular Cloud 1 South Region
Jun Hashimoto, Motohide Tamura, Ryo Kandori +8
We present the polarization images in the , , & bands of the Orion Molecular Cloud 1 South region. The polarization images clearly show at least six infrared reflection…
SCExAO/CHARIS Near-Infrared Scattered-Light Imaging and Integral Field Spectropolarimetry of the AB Aurigae Protoplanetary System
Erica Dykes, Thayne Currie, Kellen Lawson +21
We analyze near-infrared integral field spectropolarimetry of the AB Aurigae protoplanetary disk and protoplanet (AB Aur b), obtained with SCExAO/CHARIS in 22 wavelength channels c…
Practical X-ray Gastric Cancer Diagnostic Support Using Refined Stochastic Data Augmentation and Hard Boundary Box Training
Hideaki Okamoto, Quan Huu Cap, Takakiyo Nomura +3
Endoscopy is widely used to diagnose gastric cancer and has a high diagnostic performance, but it must be performed by a physician, which limits the number of people who can be dia…
A Common Proper Motion Stellar Companion to HAT-P-7
Norio Narita, Yasuhiro H. Takahashi, Masayuki Kuzuhara +51
We report that HAT-P-7 has a common proper motion stellar companion. The companion is located at arcsec to the east and estimated as an M5.5V dwarf based on its colors. W…
The SEEDS High Contrast Imaging Survey of Exoplanets around Young Stellar Objects
Taichi Uyama, Jun Hashimoto, Masayuki Kuzuhara +49
We present high-contrast observations of 68 young stellar objects (YSOs) explored as part of the SEEDS survey on the Subaru telescope. Our targets are very young (10 Myr) stars,…
The SEEDS Direct Imaging Survey for Planets and Scattered Dust Emission in Debris Disk Systems
Markus Janson, Timothy D. Brandt, Amaya Moro-Martin +49
Debris disks around young main-sequence stars often have gaps and cavities which for a long time have been interpreted as possibly being caused by planets. In recent years, several…
Near-Infrared Polarimetry of the Eagle Nebula (M16)
Koji Sugitani, Makoto Watanabe, Motohide Tamura +10
We carried out deep and wide (about 8' x 8') JHKs imaging polarimetry in the southern region of the Eagle Nebula (M16). The polarization intensity map reveals that two YSOs with ne…
A Resolved Near-Infrared Image of The Inner Cavity in The GM Aur Transitional Disk
Daehyeon Oh, Jun Hashimoto, Joseph C. Carson +47
We present high-contrast H-band polarized intensity (PI) images of the transitional disk around the young solar-like star GM Aur. The near-infrared direct imaging of the disk was d…
Near-IR High-Resolution Imaging Polarimetry of the SU Aur Disk: Clues for Tidal Tails?
Jerome de Leon, Michihiro Takami, Jennifer L. Karr +53
We present new high-resolution (0\farcs09) -band imaging observations of the circumstellar disk around the T Tauri star SU Aur. Our observations with Subaru-HiCIAO have re…
ALMA Band 6 high-resolution observations of the transitional disk around SY Cha
Ryuta Orihara, Munetake Momose, Takayuki Muto +10
In this study, we reported the results of high-resolution (0.14 arcsec) Atacama Large Millimeter/submillimeter Array (ALMA) observations of the 225 GHz dust continuum and CO molecu…
Extended High Circular Polarization in the Orion Massive Star Forming Region: Implications for the Origin of Homochirality in the Solar System
Tsubasa Fukue, Motohide Tamura, Ryo Kandori +7
We present a wide-field (~6'x6') and deep near-infrared (Ks band: 2.14 micro m) circular polarization image in the Orion nebula, where massive stars and many low-mass stars are for…
Accretion Properties of PDS 70b with MUSE
Jun Hashimoto, Yuhiko Aoyama, Mihoko Konishi +4
We report a new evaluation of the accretion properties of PDS~70b obtained with VLT/MUSE. The main difference from previous studies in Haffert et al. (2019) and Aoyama & Ikoma (201…
Recovery of the Candidate Protoplanet HD 100546 b with Gemini/NICI and Detection of Additional (Planet-Induced?) Disk Structure at Small Separations
Thayne Currie, Takayuki Muto, Tomoyuki Kudo +23
We report the first independent, second-epoch (re-)detection of a directly-imaged protoplanet candidate. Using high-contrast imaging of HD 100546 taken with the Near-Inf…
High-Contrast Near-Infrared Imaging Polarimetry of the Protoplanetary Disk around RY Tau
Michihiro Takami, Jennifer L. Karr, Jun Hashimoto +50
We present near-infrared coronagraphic imaging polarimetry of RY Tau. The scattered light in the circumstellar environment was imaged at H-band at a high resolution (~0".05) for th…
The Fundamental Stellar Parameters of FGK Stars in the SEEDS Survey
Evan A. Rich, John P. Wisniewski, Michael W. McElwain +59
Large exoplanet surveys have successfully detected thousands of exoplanets to-date. Utilizing these detections and non-detections to constrain our understanding of the formation an…
A Substellar Companion to Pleiades HII 3441
Mihoko Konishi, Taro Matsuo, Kodai Yamamoto +55
We find a new substellar companion to the Pleiades member star, Pleiades HII 3441, using the Subaru telescope with adaptive optics. The discovery is made as part of the high-contra…
Differences in the gas and dust distribution in the transitional disk of a sun-like young star, PDS 70
Zachary C. Long, Eiji Akiyama, Michael Sitko +22
We present ALMA 0.87 mm continuum, HCO+ J=4--3 emission line, and CO J=3--2 emission line data of the disk of material around the young, Sun-like star PDS 70. These data reveal the…
The Eccentric Cavity, Triple Rings, Two-Armed Spirals, and Double Clumps of the MWC 758 Disk
Ruobing Dong, Sheng-yuan Liu, Josh Eisner +15
Spatially resolved structures in protoplanetary disks hint at unseen planets. Previous imaging observations of the transitional disk around MWC 758 revealed an inner cavity, a ring…
A concordant scenario to explain FU Ori from deep centimeter and millimeter interferometric observations
Hauyu Baobab Liu, Eduard I. Vorobyov, Ruobing Dong +13
We resolved FU Ori at 29-37 GHz using the JVLA with 0.07 resolution, and performed the complementary JVLA 8-10 GHz observations, the SMA 224 GHz and 272 GHz observations,…
Complex Scattered Radiation Fields and Multiple Magnetic Fields in the Protostellar Cluster in NGC 2264
Jungmi Kwon, Motohide Tamura, Ryo Kandori +9
Near-infrared (IR) imaging polarimetry in the J, H, and Ks bands has been carried out for the protostellar cluster region around NGC 2264 IRS 2 in the Monoceros OB1 molecular cloud…
Subaru/HiCIAO imaging of LkH 330 - multi-band detection of the gap and spiral-like structures
Taichi Uyama, Jun Hashimoto, Takayuki Muto +56
We present - and -bands observations of the LkH 330 disk with a multi-band detection of the large gap and spiral-like structures. The morphology of the outer disk…
Near-Infrared Imaging of a Spiral in the CQ Tau Disk
Taichi Uyama, Takayuki Muto, Dimitri Mawet +28
We present -band Keck/NIRC2 imaging and -band Subaru/AO188+HiCIAO polarimetric observations of CQ Tau disk with a new spiral arm. Apart from the spiral feature our obs…
Near-Infrared Imaging Polarimetry of LkCa 15: A Possible Warped Inner Disk
Daehyeon Oh, Jun Hashimoto, Motohide Tamura +48
We present high-contrast H-band polarized intensity images of the transitional disk around the young solar-like star LkCa 15. By utilizing Subaru/HiCIAO for polarimetric differenti…
Anisotropic Ionizing Illumination from an M-type Pre-main Sequence Star, DM Tau
Yuka Terada, Hauyu Baobab Liu, David Mkrtichian +6
The powerful, high-energy magnetic activities of young stars play important roles in the magnetohydrodynamics in the innermost parts of the protoplanetary disks. In addition, the a…
ALMA observation of the protoplanetary disk around WW Cha: faint double-peaked ring and asymmetric structure
Kazuhiro D. Kanagawa, Jun Hashimoto, Takayuki Muto +13
We present Atacama Large Millimeter/submillimeter Array (ALMA) Band 6 observations of dust continuum emission of the disk around WW Cha. The dust continuum image shows a smooth dis…
Planet Formation in AB Aurigae: Imaging of the inner gaseous Spirals observed inside the Dust Cavity
Ya-Wen Tang, Stephane Guilloteau, Anne Dutrey +13
We report the results of ALMA observations of a protoplanetary disk surrounding the Herbig Ae star AB Aurigae. We obtained high-resolution (0.1"; 14 au) images in CO (J=2-1)…
Extreme Asymmetry in the Disk of V1247 Ori
Yurina Ohta, Misato Fukagawa, Michael L. Sitko +60
We present the first near-infrared scattered-light detection of the transitional disk around V1247 Ori, which was obtained using high-resolution polarimetric differential imaging o…
ALMA Reveals a Misaligned Inner Gas Disk inside the Large Cavity of a Transitional Disk
Satoshi Mayama, Eiji Akiyama, Olja PaniÄ +15
Pairs of azimuthal intensity decrements at near symmetric locations have been seen in a number of protoplanetary disks. They are most commonly interpreted as the two shadows cast b…
The shadow knows: using shadows to investigate the structure of the pretransitional disk of HD 100453
Zachary C. Long, Rachel B. Fernandes, Michael Sitko +16
We present GPI polarized intensity imagery of HD 100453 in Y-, J-, and K1 bands which reveals an inner gap ( au), an outer disk ( au) with two prominent spiral arms,…
Detailed structure of the outer disk around HD 169142 with polarized light in H-band
Munetake Momose, Ayaka Morita, Misato Fukagawa +59
Coronagraphic imagery of the circumstellar disk around HD 169142 in H-band polarized intensity (PI) with Subaru/HiCIAO is presented. The emission scattered by dust particles at the…
Predictions of Dust Continuum Emission from a Potential Circumplanetary Disk: A Case Study of the Planet Candidate AB Aurigae b
Yuhito Shibaike, Jun Hashimoto, Ruobing Dong +3
Gas accreting planets embedded in protoplanetary disks are expected to show dust thermal emission from their circumplanetary disks (CPDs). However, a recently reported gas accretin…
Analyses of Multiple Balmer Emission Lines from Accreting Brown Dwarfs and Very Low Mass Stars
Jun Hashimoto, Yuhiko Aoyama
A planetary growth rate, a.k.a., the mass accretion rate, is a fundamental parameter in planet formation, as it determines a planet's final mass. Planetary mass accretion rates hav…
Asymmetric dust accumulation of the PDS 70 disk revealed by ALMA Band 3 observations
Kiyoaki Doi, Akimasa Kataoka, Hauyu Baobab Liu +5
The PDS 70 system, hosting two planets within its disk, is an ideal target for examining the effect of planets on dust accumulation, growth, and ongoing planet formation. Here, we…
High-Resolution Near-Infrared Polarimetry and Sub-Millimeter Imaging of FS Tau A: Possible Streamers in Misaligned Circumbinary Disk System
Yi Yang, Eiji Akiyama, Thayne Currie +56
We analyzed the young (2.8-Myr-old) binary system FS Tau A using near-infrared (H-band) high-contrast polarimetry data from Subaru/HiCIAO and sub-millimeter CO (J=2-1) line emissio…
High-Resolution Submillimeter and Near-Infrared Studies of the Transition Disk around Sz 91
Takashi Tsukagoshi, Munetake Momose, Jun Hashimoto +55
To reveal the structures of a transition disk around a young stellar object in Lupus, Sz 91, we have performed aperture synthesis 345 GHz continuum and CO(3--2) observations with t…
Absence of Significant Cool Disks in Young Stellar Objects Exhibiting Repetitive Optical Outbursts
Hauyu Baobab Liu, Roberto Galván-Madrid, Eduard I. Vorobyov +10
We report Submillimeter Array (SMA) 1.3 mm high angular resolution observations towards the four EXor type outbursting young stellar objects (YSOs) VY Tau, V1118 Ori, V1143 Ori, an…
Discovery of the Coldest Imaged Companion of a Sun-Like Star
Christian Thalmann, Joseph Carson, Markus Janson +17
We present the discovery of a brown dwarf or possible planet at a projected separation of 1.9" = 29 AU around the star GJ 758, placing it between the separations at which substella…
Mapping the merging zone of late infall in the AB Aur planet-forming system
Jessica Speedie, Ruobing Dong, Richard Teague +10
Late infall events challenge the traditional view that planet formation occurs without external influence. Here we present deep ALMA CO and SO observ…
Analyzing JWST/NIRSpec Hydrogen Line Detections at TWA 27B: Constraining Accretion Properties and Geometry
Yuhiko Aoyama, Gabriel-Dominique Marleau, Jun Hashimoto
Hydrogen lines from forming planets are crucial for understanding planet formation. However, the number of planetary hydrogen line detections is still limited. Recent JWST/NIRSpec…
Gap Opening and Inner Disk Structure in the Strongly Accreting Transition Disk of DM Tau
Logan Francis, Nienke van der Marel, Doug Johnstone +7
Large inner dust gaps in transition disks are frequently posited as evidence of giant planets sculpting gas and dust in the disk, or the opening of a gap by photoevaporative winds.…
Grain Growth in the Dust Ring with Crescent around Very Low Mass Star ZZ Tau IRS with JVLA
Jun Hashimoto, Hauyu Baobab Liu, Ruobing Dong +2
The azimuthal asymmetries of dust rings in protoplanetary disks such as a crescent around young stars are often interpreted as dust traps, and thus as ideal locations for planetesi…
ALMA High-resolution Multiband Analysis for the Protoplanetary Disk around TW Hya
Takashi Tsukagoshi, Hideko Nomura, Takayuki Muto +10
We present a high-resolution (2.5 au) multiband analysis of the protoplanetary disk around TW Hya using ALMA long baseline data at Bands 3, 4, 6, and 7. We aim to reconstruct a hig…
Indications of M-dwarf Deficits in the Halo and Thick Disk of the Galaxy
Mihoko Konishi, Hiroshi Shibai, Takahiro Sumi +55
We compared the number of faint stars detected in deep survey fields with the current stellar distribution model of the Galaxy and found that the detected number in the H band is s…
High-Contrast Imaging of Intermediate-Mass Giants with Long-Term Radial Velocity Trends
Tsuguru Ryu, Bun'ei Sato, Masayuki Kuzuhara +62
A radial velocity (RV) survey for intermediate-mass giants has been operated for over a decade at Okayama Astrophysical Observatory (OAO). The OAO survey has revealed that some gia…
ALMA 873 m Polarization Observations of the PDS~70 Disk
Hauyu Baobab Liu, Kiyoaki Doi, Simon Casassus +4
At a 112.4 pc distance, the PDS70 protoplanetary disk is a rare case that has been confirmed to host two accreting planets. This makes it the most important laboratory for studying…