Jun‐Ichi Morino

National Astronomical Observatory of Japan

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Trends

Author Order

Document Type

Co-Authors

Masahiko Hayashi

National Astronomical Observatory of Japan

Motohide Tamura

The University of Tokyo

Hiroshi Suto

Japan Aerospace Exploration Agency

Tomonori Usuda

National Astronomical Observatory of Japan

Tomoyuki Kudo

National Astronomical Observatory of Japan

Hideki Takami

Nagoya University

K. W. Hodapp

University of Hawaiʻi at Mānoa

Ryo Kandori

Astrobiology Center

Nobuhiko Kusakabe

Astrobiology Center

Saeko S. Hayashi

National Astronomical Observatory of Japan

Cooperative Institutions

National Astronomical Observatory of Japan

218

Centre National de la Recherche Scientifique

133

The University of Tokyo

132

National Institutes of Natural Sciences

110

The Graduate University for Advanced Studies, SOKENDAI

Subaru (Japan)

California Institute of Technology

Université Paris Cité

Max Planck Society

Max Planck Institute for Astronomy

Author Statistics

Papers

Citation

H-Index

i-10 index

Research Field

AMANOGAWA-2SB survey: a northern galactic plane survey in ¹²CO (J = 2 − 1) and ¹³CO (J = 2 − 1) with the Amanogawa telescope

Proceedings of the International Astronomical Union (2012)

Toshihiro Handa T. Yoda Kotaro Kohno Taku Nakajima Jun‐Ichi Morino

Abstract We performed 12 CO( J = 2 − 1) and 13 CO( J = 2 − 1) line surveys of the galactic plane using the AMANOGAWA telescope (Nakajima et al . 2007) which covers 5° ≤ l ≤ 180° on a 7'.5 grid. The telescope beamsize and velocity resolution are 8.7′ ± 0.4′ and 1.3 km s −1 . The resultant rms noise level is typically 0.12 K in T A *. We found a linear correlation between 12 CO( J = 2 − 1) and 12 CO( J = 1 − 0) and a curved correlation between 12 CO( J = 2 − 1) and 13 CO ( J = 2 − 1), although the intensity ratios of these three lines have intrinsic variation. These correlations can be reproduced with simple radiative transfer equations suggesting some restrictions on the physical quantities of molecular gas on a galactic scale.

Galactic plane

Line (geometry)

10.1017/s1743921313000628

Cite

Citations (0)

4.7. The CO 2–1/1–0 ratio in the disk and center of the Milky Way Galaxy

Symposium - International Astronomical Union (1998)

Tetsuo Hasegawa Jun‐Ichi Morino Tsuyoshi Sawada Toshihiro Handa Kumiko Sato

We are conducting a survey of the CO J =2-1 line emission in the southern Milky Way (the Tokyo-Onsala-ESO-Calán Galactic CO survey), using the 60-cm radio telescope ( VST2 ) in La Silla, Chile. It is combined with the northern survey made with the identical telescope ( VST1 ) at Nobeyama ( e.g. , Sakamoto et al. 1995), and is directly comparable with the Columbia survey of the CO J =1-0 emission ( e.g. , Dame et al. 1987).

Center (category theory)

10.1017/s0074180900084539

Cite

Citations (0)

A New 60-cm Radio Survey Telescope with the Sideband-Separating SIS Receiver for the 200 GHz Band

Publications of the Astronomical Society of Japan (2007)

Taku Nakajima Masahiro Kaiden Jun Korogi Kimihiro Kimura Yoshinori Yonekura

Abstract We have upgraded the 60-cm radio survey telescope located in Nobeyama, Japan. We developed a new waveguide-type sideband-separating SIS mixer for the telescope, which enables the simultaneous detection of distinct molecular emission lines in both the upper and lower sidebands. Over the RF frequency range of 205–240 GHz, the single-sideband receiver noise temperatures of the new mixer are 40–100 K for the 4.0–8.0 GHz IF frequency band. The image rejection ratios are greater than 10 dB over the same range. For dual IF signals obtained by the receiver, we have developed two sets of acousto-optical spectrometers and a telescope control system. Using the new telescope system, we successfully detected the $^{12}$CO ($J =$ 2$-$1) and $^{13}$CO ($J =$ 2$-$1) emission lines simultaneously toward Orion KL in 2005 March. Using the waveguide-type sideband-separating SIS mixer for the 200 GHz band, we initiated the first simultaneous $^{12}$CO ($J =$ 2$-$1) and $^{13}$CO ($J =$ 2$-$1) survey of the galactic plane as well as large-scale mapping observations of nearby molecular clouds.

Compatible sideband transmission

Radio spectrum

10.1093/pasj/59.5.1005

Cite

Citations (22)

Selection of Nearby Star Targets for the Subaru Strategic Exploration of Exoplanets and Disks

AIP conference proceedings (2009)

Ryo Kandori Motohide Tamura Jun‐Ichi Morino Miki Ishii Ryuji Suzuki

SEEDS (the Subaru Strategic Exploration of Exoplanets and Disks with Hi‐CIAO/AO188) is a strategic five‐year campaign of direct imaging surveys of exoplanets/disks using the Subaru telescope equipped with the new adaptive optics system AO188 and our new high‐contrast instrument, HiCIAO. The goals of the survey are to address the following key issues in exoplanet/disk sciences: (1) the detection and census of exoplanets; (2) the evolution of protoplanetary and debris disks; and (3) the link between exoplanets and disks. Targets prepared for the SEEDS exoplanet searches are in four categories, including nearby stars. We present our scientific motivations and current status of the SEEDS target selection in the nearby stars category.

Subaru Telescope

Direct imaging

Optical telescope

10.1063/1.3215857

Cite

Citations (0)

POTENTIAL MEMBERS OF STELLAR KINEMATICAL GROUPS WITHIN 20 pc OF THE SUN

The Astronomical Journal (2010)

Tadashi Nakajima Jun‐Ichi Morino Misato Fukagawa

We analyze the kinematical histories of stars within 20 pc of the Sun, for which three-dimensional spatial coordinates and three-dimensional velocity vectors are available. From this sample, we extract members of stellar kinematical groups (SKGs) in the following manner. First, in the three-dimensional velocity space centered on the local standard of rest, we consider a sphere with a radius of 8 km s−1 centered on the mean velocity vector of a particular SKG. Around each SKG velocity center, we have found a significant excess of stars compared to background stars. For each candidate, in the three-dimensional spatial coordinate space, its trajectory is traced back in time by the age of the relevant SKG, to estimate the distance from the SKG center at the time of the SKG's birth by the epicycle approximation and vertical harmonic motion. It often happens that a star is a candidate member of multiple SKGs. Then we rank the candidacy to multiple SKGs based on the smallness of distance separations. In this manner, we have kinematically selected 74 candidate members of SKGs out of a sample of 383 stars. If we take into account stellar properties, the number is reduced to 68.

Proper motion

Star (game theory)

Celestial sphere

Radial velocity

10.1088/0004-6256/140/3/713

Cite

Citations (16)

High-resolution Near-infrared Polarimetry and Submillimeter Imaging of FS Tau A: Possible Streamers in Misaligned Circumbinary Disk System

The Astrophysical Journal (2020)

Yi Yang Eiji Akiyama Thayne Currie Ruobing Dong Jun Hashimoto

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 emission data from ALMA. Both the near-infrared and sub-millimeter observations reveal several clear structures extending to $\sim$240 AU from the stars. Based on these observations at different wavelengths, we report the following discoveries. One arm-like structure detected in the near-infrared band initially extends from the south of the binary with a subsequent turn to the northeast, corresponding to two bar-like structures detected in ALMA observations with an LSRK velocity of 1.19-5.64 km/s. Another feature detected in the near-infrared band extends initially from the north of the binary, relating to an arm-like structure detected in ALMA observations with an LSRK velocity of 8.17-16.43 km/s. From their shapes and velocities, we suggest that these structures can mostly be explained by two streamers that connect the outer circumbinary disk and the central binary components. These discoveries will be helpful for understanding the evolution of streamers and circumstellar disks in young binary systems.

Circumbinary planet

Circumstellar disk

10.3847/1538-4357/ab64f9

Cite

Citations (3)

A submillimetre imaging polarimeter at the James Clerk Maxwell Telescope

Monthly Notices of the Royal Astronomical Society (2003)

J. S. Greaves W. S. Holland T. Jenness A. Chrysostomou D. S. Berry

A polarimeter has been built for use with the Submillimetre Common-User Bolometer Array (SCUBA), on the James Clerk Maxwell Telescope (JCMT) in Hawaii. SCUBA is the first of a new generation of highly sensitive submillimetre cameras, and the UK/Japan Polarimeter adds a polarimetric imaging/photometry capability in the wavelength range 350 to 2000 μm. Early science results range from measuring the synchrotron polarization of the black hole candidate Sgr A* to mapping magnetic fields inferred from polarized dust emission in Galactic star-forming clouds. We describe the instrument design, performance, observing techniques and data reduction processes, along with an assessment of the current and future scientific capability.

Polarimeter

South Pole Telescope

10.1046/j.1365-8711.2003.06230.x

Cite

Citations (66)

Resolved Near-Infrared Image of Inner Cavity in GM Aur Transitional Disk

arXiv (Cornell University) (2016)

Daehyeon Oh Jun Hashimoto J. Carson M. Janson Jungmi Kwon

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 derived by polarimetric differential imaging using the Subaru 8.2-m Telescope and HiCIAO. An angular resolution and an inner working angle of 0.07 and r~0.05, respectively, were obtained. We clearly resolved a large inner cavity, with a measured radius of 18+/-2 au, which is smaller than that of a submillimeter interferometric image (28 au). This discrepancy in the cavity radii at near-infrared and submillimeter wavelengths may be caused by a 3-4M_Jup planet about 20 au away from the star, near the edge of the cavity. The presence of a near-infrared inner is a strong constraint on hypotheses for inner cavity formation in a transitional disk. A dust filtration mechanism has been proposed to explain the large cavity in the submillimeter image, but our results suggest that this mechanism must be combined with an additional process. We found that the PI slope of the outer disk is significantly different from the intensity slope obtained from HST/NICMOS, and this difference may indicate the grain growth process in the disk.

Source

Cite

Citations (0)

Search for Outer Massive Bodies around Transiting Planetary Systems: Candidates of Faint Stellar Companions around HAT-P-7

Publications of the Astronomical Society of Japan (2010)

Norio Narita Tomoyuki Kudo C. Bergfors Makiko Nagasawa C. Thalmann

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 to have a highly tilted orbit, massive bodies such as giant planets, brown dwarfs, or a binary star are expected to exist in the outer region of this system. We show that there are indeed two candidates for distant faint stellar companions around HAT-P-7. We discuss possible roles played by such companions on the orbital evolution of HAT-P-7b. We conclude that as there is a third body in the system as reported by Winn et al. (2009, ApJL, 763, L99), the Kozai migration is less likely while planet-planet scattering is possible.

Direct imaging

Orbit (dynamics)

Giant planet

10.1093/pasj/62.3.779

Cite

Citations (49)

Near-Infrared Spectroscopy of Faint Companions around Young Stellar Objects Associated with the Taurus Molecular Cloud

Publications of the Astronomical Society of Japan (2008)

Yoichi Itoh Motohide Tamura Masahiko Hayashi Yumiko Oasa Saeko S. Hayashi

Abstract We have conducted near-infrared spectroscopy of 26 faint objects around young stellar objects in the Taurus molecular cloud. These objects were detected during a course of near-infrared coronagraphic searches for companions around 72 young stellar objects with the Subaru Telescope and the near-infrared coronagraph CIAO (coronagraphic imager with adaptive optics). A comparison of the Subaru and HST archive images revealed that three central stars and faint companions share common proper motions, suggesting that they are physically associated with each other. None of the 26 sources show deep water absorption bands at near-infrared, except for DH Tau B. This result indicates that all of them, but DH Tau B, have a high photospheric temperature or a large amount of excess from circumstellar materials.

Subaru Telescope

Coronagraph

Infrared telescope

Young stellar object

Infrared excess

10.1093/pasj/60.2.209

Cite

Citations (10)