471 citations · 1.2k across the 36 of their papers we have counts for
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Re-analysis of the First Fringe with 2-Beam in the VERA System from Archive Data
Makoto Miyoshi
We report results from re-analysis of the visibility data of the first 2-beam observations with VERA (VLBI Exploration of Radio Astrometry), previously reported by Honma et al., 20…
An Approach Detecting the Event Horizon of Sgr A*
Makoto Miyoshi, Seiji Kameno, Jose K. Ishituka +3
Imaging the vicinity of a black hole is one of the ultimate goals of VLBI astronomy. The closest massive black hole, Sgr A*, located at the Galactic center, is the leading candidat…
Flares of Sagittarius a* at Millimeter Wavelengths
Atsushi Miyazaki, Takahiro Tsutsumi, Makoto Miyoshi +2
We have performed monitoring observations of the flux density toward the Galactic center compact radio source, Sagittarius A* (Sgr A*), which is a supermassive black hole, from 199…
An Approach Detecting the Event Horizon of SgrA*
M. Miyoshi
Imaging the vicinity of black hole is one of the ultimate goals of VLBI astronomy. The closest massive black hole, SgrA*, located at Galactic center is the leading candidate for su…
Distance of W3(OH) by VLBI annual parallax measurement
K. Hachisuka, A. Brunthaler, Y. Hagiwara +4
The most powerful tool for measuring distances within our Galaxy is the annual parallax. We carried out phase-referencing VLBI observations of HO masers in the star forming r…
A search for extragalactic H2O maser emission towards IRAS galaxies II - Discovery of an H2O maser in the Seyfert 1 galaxy NGC 4051
Yoshiaki Hagiwara, Philip J Diamond, Makoto Miyoshi +2
Water vapor maser emission in the 6_{16}-5_{23} transition towards the narrow-line Seyfert 1 (NLS1) galaxy NGC 4051 has been discovered during an ongoing single-dish extragalactic…
Location of H2O maser in the double-nuclei system of NGC6240
Yoshiaki Hagiwara, Philip J. Diamond, Makoto Miyoshi
We performed VLA observations of the 22 GHz H2O maser emission in the merging galaxy NGC6240, which hosts the well-known double active nuclei. In a previous paper, we reported on t…
The 3-D kinematics of water masers around the semiregular variable RT Virginis
Hiroshi Imai, Katsunori M. Shibata, Kevin B. Marvel +6
We report observations of water masers around the semiregular variable RT Virginis (RT Vir), which have been made with the Very Long Baseline Array (VLBA) of the National Radio Ast…
Observations of SiO Maser Sources within a Few Parsec from the Galactic Center
Shuji Deguchi, Takahiro Fujii, Makoto Miyoshi +1
Mapping and monitoring observations of SiO maser sources near the Galactic center were made with the Nobeyama 45-m telescope at 43 GHz. Rectangular mapping an area of approximately…
A search for extragalactic H2O maser emission towards IRAS galaxies - Detection of a maser from an infrared-luminous merger, NGC6240
Y. Hagiwara, P. J. Diamond, M. Miyoshi
We report the result of an on-going survey for 22 GHz H2O maser emission towards infrared luminous galaxies. The observed galaxies were selected primarily from the IRAS bright gala…
A 4% Geometric Distance to the Galaxy NGC4258 from Orbital Motions in a Nuclear Gas Disk
J. R. Herrnstein, J. M. Moran, L. J. Greenhill +6
The water maser in the mildly active nucleus in the nearby galaxy NGC4258 traces a thin, nearly edge-on, subparsec-scale Keplerian disk. Using the technique of very long baseline i…
VLBA Continuum Observations of NGC 4258: Constraints on an Advection-Dominated Accretion Flow
J. R. Herrnstein, L. J. Greenhill, J. M. Moran +4
We report a 3 sigma upper limit of 220 microJanskys on any 22-GHz continuum emission coincident with the central engine in NGC 4258. If NGC 4258 is powered by an advection-dominate…