176 citations · 1.8k across the 76 of their papers we have counts for
76 papers
A Primordial Origin for the Gas-Rich Debris Disks Around Intermediate-Mass Stars
Riouhei Nakatani, Neal J. Turner, Yasuhiro Hasegawa +4
While most debris disks consist of dust with little or no gas, a fraction has significant amounts of gas detected via emission lines of CO, ionized carbon, and/or atomic oxygen. Al…
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.…
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…
Hyperion: The origin of the stars A far-UV space telescope for high-resolution spectroscopy over wide fields
Erika Hamden, David Schiminovich, Shouleh Nikzad +30
We present Hyperion, a mission concept recently proposed to the December 2021 NASA Medium Explorer announcement of opportunity. Hyperion explores the formation and destruction of m…
Halting Migration in Magnetospherically Sculpted Protoplanetary Disks
Tze Yeung Mathew Yu, Brad Hansen, Yasuhiro Hasegawa
We present a physically motivated model for the manner in which a stellar magnetic field sculpts the inner edge of a protoplanetary disk, and examine the consequence for the migrat…
Solid Accretion onto Neptune-Mass Planets I: In-Situ Accretion and Constraints from the metallicity of Uranus and Neptune
Yasuhiro Hasegawa
The currently available, detailed properties (e.g., isotopic ratios) of solar system planets may provide guides for constructing better approaches of exoplanet characterization. Wi…
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…
Determining dispersal mechanisms of protoplanetary disks using accretion and wind mass loss rates
Yasuhiro Hasegawa, Thomas J. Haworth, Keri Hoadley +6
Understanding the origin of accretion and dispersal of protoplanetary disks is fundamental for investigating planet formation. Recent numerical simulations show that launching wind…
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-resolutio…
Magnetic Fields and Accreting Giant Planets around PDS 70
Yasuhiro Hasegawa, Kazuhiro D. Kanagawa, Neal J. Turner
The recent high spatial/spectral resolution observations have enabled constraining formation mechanisms of giant planets, especially at the final stages. The current interpretation…
The architecture of multi-planet systems as a tracer of their formation mechanisms
Udit Arora, Yasuhiro Hasegawa
Exoplanets observed by the {\it Kepler} telescope exhibit a bi-modal, radius distribution, which is known as the radius gap. We explore an origin of the radius gap, focusing on mul…
Formation of rims around chondrules via porous aggregate accretion
Yuji Matsumoto, Yasuhiro Hasegawa, Nozomi Matsuda +1
Chondrules are often surrounded by fine-grained rims or igneous rims. The properties of these rims reflect their formation histories. While the formation of fine-grained rims is mo…
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…
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…
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…
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…
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…
Aggregate Growth and Internal structures of Chondrite Parent Bodies Forming from Dense Clumps
Yuji Matsumoto, Shigeru Wakita, Yasuhiro Hasegawa +1
Major components of chondrites are chondrules and matrix. Measurements of the volatile abundance in Semarkona chondrules suggest that chondrules formed in a dense clump that had a…
Planet formation and migration near the silicate sublimation front in protoplanetary disks
Mario Flock, Neal J. Turner, Gijs D. Mulders +3
The increasing number of newly detected exoplanets at short orbital periods raises questions about their formation and migration histories. A particular puzzle that requires explan…
The Properties of Planetesimal Collisions under Jupiter's Perturbation and the Application to Chondrule Formation via Impact Jetting
Shoichi Oshino, Yasuhiro Hasegawa, Shigeru Wakita +1
Understanding chondrule formation provides invaluable clues about the origin of the solar system. Recent studies suggest that planetesimal collisions and the resulting impact melts…
The Potential of Exozodiacal Disks Observations with the WFIRST Coronagraph Instrument
B. Mennesson, V. Bailey, J. Kasdin +60
The Wide Field Infrared Survey Telescope (WFIRST) Coronagraph Instrument (CGI) will be the first high-performance stellar coronagraph using active wavefront control for deep starli…
Diagnosing 0.1-10 au scale morphology of the FU\,Ori disk using ALMA and VLTI/GRAVITY
Hauyu Baobab Liu, Antoine Mérand, Joel D. Green +11
We report new Atacama Large Millimeter/submillimeter Array Band 3 (86-100 GHz; 80 mas angular resolution) and Band 4 (146-160 GHz; 50 mas angular resolution) observatio…
Close-in giant-planet formation via in-situ gas accretion and their natal disk properties
Yasuhiro Hasegawa, Tze Yeung Mathew Yu, Bradley M. S. Hansen
The origin of close-in Jovian planets is still elusive. We examine the in-situ gas accretion scenario as a formation mechanism of these planets. We reconstruct natal disk propertie…
The Heavy-element Content Trend of Planets: A Tracer of their Formation Sites
Yasuhiro Hasegawa, Bradley M. S. Hansen, Gautam Vasisht
Identification of the main planet formation site is fundamental to understanding how planets form and migrate to the current locations. We consider the heavy-element content trend…