399 citations · 6.3k across the 159 of their papers we have counts for
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Near-infrared spectra of chemically peculiar stars and applications to kilonova spectra
Nanae Domoto, Masaomi Tanaka, Wako Aoki +11
Kilonova spectra provide information on rapid neutron-capture nucleosynthesis in neutron star mergers. However, it remains challenging to identify individual elements in kilonova s…
Revealing α-Element's Past with Subaru/IRD: Oxygen Abundance of 35 Very Metal-Poor Stars from Near-IR OH lines
Bakuh Danang Setyo Budi, Wako Aoki, Nicholas Storm +10
Oxygen abundances in very and extremely metal-poor (V/EMP) stars provide critical constraints on early massive stars' nucleosynthesis. An Oxygen abundance analysis is presented for…
Discovery of a Low-Mass Companion to the Accelerating Star HIP 53005 with Strongly Conflicting Mass Estimates
Taichi Uyama, Thayne Currie, Jerry W. Xuan +22
We present the discovery of a low-mass companion located at 0\farcs{}85 () from the early-type 1.2 Gyr-old star HIP 53005 using direct imagin…
OASIS Survey Direct Imaging and Astrometric Discovery of HIP 71618 B: A Substellar Companion Suitable for the Roman Coronagraph Technology Demonstration
Mona El Morsy, Thayne Currie, Brianna Lacy +27
We present the OASIS survey program discovery of a substellar companion orbiting the young A1V star HIP 71618, detected using precision astrometry from Gaia and Hipparcos and high-…
CoronaGraph Instrument Reference stars for Exoplanets (CorGI-REx) I. Preliminary Vetting and Implications for the Roman Coronagraph and Habitable Worlds Observatory
Justin Hom, Schuyler G. Wolff, Catherine A. Clark +28
The upcoming Roman Coronagraph will be the first high-contrast instrument in space capable of high-order wavefront sensing and control technologies, a critical technology demonstra…
Direct Imaging Explorations for Companions from the Subaru/IRD Strategic Program II; Discovery of a Brown-dwarf Companion around a Nearby mid-M~dwarf LSPM~J1446+4633
Taichi Uyama, Masayuki Kuzuhara, Charles Beichman +35
We report the discovery of a new directly-imaged brown dwarf companion with Keck/NIRC2+pyWFS around a nearby mid-type M~dwarf LSPM~J1446+4633 (hereafter J1446). The -band contr…
Elemental abundances of 44 very metal-poor stars determined from Subaru/IRD near-infrared spectra
Wako Aoki, Timothy C. Beers, Satoshi Honda +12
Abundances of five elements, Na, Mg, Al, Si, and Sr, are investigated for 44 very metal-poor stars (-4.0 < [Fe/H] < -1.5) in the Galactic halo system based on an Local Thermodinami…
Direct-imaging Discovery of a Substellar Companion Orbiting the Accelerating Variable Star, HIP 39017
Taylor L. Tobin, Thayne Currie, Yiting Li +23
We present the direct-imaging discovery of a substellar companion (a massive planet or low-mass brown dwarf) to the young, Doradus-type variable star, HIP 39017 (HD 65526). The…
Direct Imaging Explorations for Companions around Mid-Late M Stars from the Subaru/IRD Strategic Program
Taichi Uyama, Charles Beichman, Masayuki Kuzuhara +32
The Subaru telescope is currently performing a strategic program (SSP) using the high-precision near-infrared (NIR) spectrometer IRD to search for exoplanets around nearby mid/late…
SCExAO and Keck Direct Imaging Discovery of a Low-Mass Companion Around the Accelerating F5 Star HIP 5319
Noah Swimmer, Thayne Currie, Sarah Steiger +26
We present the direct imaging discovery of a low-mass companion to the nearby accelerating F star, HIP 5319, using SCExAO coupled with the CHARIS, VAMPIRES, and MEC instruments in…
Direct Imaging Discovery and Dynamical Mass of a Substellar Companion Orbiting an Accelerating Hyades Sun-like Star with SCExAO/CHARIS
Masayuki Kuzuhara, Thayne Currie, Takuya Takarada +33
We present the direct-imaging discovery of a substellar companion in orbit around a Sun-like star member of the Hyades open cluster. So far, no other substellar companions have bee…
Silicon and Strontium abundances of very metal-poor stars determined from near-infrared spectra
Wako Aoki, Timothy C. Beers, Satoshi Honda +19
Silicon and Strontium are key elements to explore the nucleosynthesis and chemical evolution of the Galaxy by measurements of very metal-poor stars. There are, however, only a few…
Elemental abundances of nearby M dwarfs based on high-resolution near-infrared spectra obtained by the Subaru/IRD survey: Proof of concept
Hiroyuki Tako Ishikawa, Wako Aoki, Teruyuki Hirano +24
Detailed chemical analyses of M dwarfs are scarce but necessary to constrain the formation environment and internal structure of planets being found around them. We present element…
SCExAO/CHARIS Direct Imaging of A Low-Mass Companion At A Saturn-Like Separation from an Accelerating Young A7 Star
Jeffrey Chilcote, Taylor Tobin, Thayne Currie +17
We present the SCExAO direct imaging discovery and characterization of a low-mass companion to the nearby young A7IV star, HD 91312. SCExAO/CHARIS (1.1-2.4 ) spectra and…
SCExAO/MEC and CHARIS Discovery of a Low Mass, 6 AU-Separation Companion to HIP 109427 using Stochastic Speckle Discrimination and High-Contrast Spectroscopy
Sarah Steiger, Thayne Currie, Timothy D. Brandt +28
We report the direct imaging discovery of a low-mass companion to the nearby accelerating A star, HIP 109427, with the Subaru Coronagraphic Extreme Adaptive Optics (SCExAO) instrum…
Characterization of M dwarfs Using Optical Mid-Resolution Spectra for Exploration of Small Exoplanets
Yohei Koizumi, Masayuki Kuzuhara, Masashi Omiya +4
We present the optical spectra of 338 nearby M dwarfs, and compute their spectral types, effective temperatures (), and radii. Our spectra have been obtained usin…
SCExAO/CHARIS Direct Imaging Discovery of a 20 au Separation, Low-Mass Ratio Brown Dwarf Companion to an Accelerating Sun-like Star
Thayne Currie, Timothy D. Brandt, Masayuki Kuzuhara +27
We present the direct imaging discovery of a substellar companion to the nearby Sun-like star, HD 33632 Aa, at a projected separation of 20 au, obtained with SCExAO/CHARIS i…
Elemental Abundances of M Dwarfs Based on High-Resolution Near-Infrared Spectra: Verification by Binary Systems
Hiroyuki Tako Ishikawa, Wako Aoki, Takayuki Kotani +4
M dwarfs are prominent targets of planet search projects, and their chemical composition is crucial to understanding the formation process or interior of orbiting exoplanets. Howev…
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…
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…
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…
Orbital characterization of GJ1108A system, and comparison of dynamical mass with model-derived mass for resolved binaries
T. Mizuki, M. Kuzuhara, K. Mede +55
We report an orbital characterization of GJ1108Aab that is a low-mass binary system in pre-main-sequence phase. Via the combination of astrometry using adaptive optics and radial v…
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.$\arcsec$…
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…