166 citations · 1.3k across the 60 of their papers we have counts for
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A Possible Shutting-Down Event of Mass Accretion in An Active Galactic Nucleus at z~1.8
Tomoki Morokuma, Malte Schramm, Toshihiro Kawaguchi +11
We present the discovery of a large gradual apparent fading event in optical and near-infrared wavelengths in a quasar at z=1.767 by a factor of 20-30 (in optical) over a period of…
Very Long Baseline Interferometry imaging of H2O maser emission in the nearby radio galaxy NGC 4261
Satoko Sawada-Satoh, Nozomu Kawakatu, Kotaro Niinuma +1
We report dual-frequency very long baseline interferometry (VLBI) observations at 22 and 43 GHz toward the nucleus of a nearby radio galaxy NGC 4261. In particular, we present a VL…
The Past and Future of East Asia to Italy: Nearly Global VLBI
Gabriele Giovannini, Yuzhu Cui, Kazuhiro Hada +29
We present here the East Asia to Italy Nearly Global VLBI (EATING VLBI) project. How this project started and the evolution of the international collaboration between Korean, Japan…
East Asian VLBI Network Observations of Active Galactic Nuclei Jets: Imaging with KaVA+Tianma+Nanshan
Yuzhu Cui, Kazuhiro Hada, Motoki Kino +74
The East Asian very-long-baseline interferometry (VLBI) Network (EAVN) is a rapidly evolving international VLBI array that is currently promoted under joint efforts among China, Ja…
Millimeter-VLBI Detection and Imaging of the Gravitationally Lensed Gamma-Ray Blazar JVAS B0218+357
Kazuhiro Hada, Kotaro Niinuma, Julian Sitarek +2
We observed the gravitationally lensed blazar JVAS B0218+357 with the KVN and VERA Array (KaVA) at 22, 43, and 86 GHz. The source has recently been identified as an active gamma-ra…
Spatially Resolved Molecular Gas Properties of Host Galaxy of Type I Superluminous Supernova SN 2017egm
Bunyo Hatsukade, Kana Morokuma-Matsui, Masao Hayashi +6
We present the results of CO(1-0) observations of the host galaxy of a Type I superluminous supernova (SLSN-I), SN2017egm, one of the closest SLSNe-I at z = 0.03063, by using the A…
The First VERA Astrometry Catalog
VERA collaboration, Tomoya Hirota, Takumi Nagayama +59
We present the first astrometry catalog from the Japanese VLBI (very long baseline interferometer) project VERA (VLBI Exploration of Radio Astrometry). We have compiled all the ast…
ALMA observations of molecular gas in the host galaxy of AT2018cow
Kana Morokuma-Matsui, Tomoki Morokuma, Nozomu Tominaga +7
We investigate the molecular gas in, and star-formation properties of, the host galaxy (CGCG 137-068) of a mysterious transient, AT2018cow, at kpc and larger scales, using archival…
The Galactic Center Lobe Filled with Thermal Plasma
Halca Nagoshi, Yuzo Kubose, Kenta Fujisawa +6
An observational result of a radio continuum and H92 radio recombination line of the Galactic Center Lobe (GCL), using the Yamaguchi 32 m radio telescope, is reported. The obtai…
Jet Kinematics of the Quasar 4C +21.35 from Observations with the KaVA Very Long Baseline Interferometry Array
Taeseok Lee, Sascha Trippe, Motoki Kino +39
We present the jet kinematics of the flat spectrum radio quasar (FSRQ) 4C +21.35 using time-resolved KaVA very long baseline interferometry array radio maps obtained from September…
VERA monitoring of the radio jet 3C 84 during 2007--2013: detection of non-linear motion
Koichiro Hiura, Hiroshi Nagai, Motoki Kino +13
We present a kinematic study of the subparsec-scale radio jet of the radio galaxy 3C 84/NGC 1275 with the VLBI Exploration of Radio Astrometry (VERA) array at 22 GHz for 80 epochs…
Obscured Star Formation in the Host Galaxies of Superluminous Supernovae
B. Hatsukade, N. Tominaga, M. Hayashi +7
We present the results of 3 GHz radio continuum observations of the 8 host galaxies of super-luminous supernovae (SLSNe) at by using the Karl G. Jansky Very Large A…
A Face-on Accretion System in High-Mass Star-Formation: Possible Dusty Infall Streams within 100 AU
Kazuhito Motogi, Tomoya Hirota, Kazuo Sorai +7
We report on interferometric observations of a face-on accretion system around the High-Mass young stellar object, G353.273+0.641. The innermost accretion system of 100 au radius w…
OISTER Optical and Near-Infrared Monitoring Observations of a Peculiar Radio-Loud Active Galactic Nucleus SDSS J110006.07+442144.3
Tomoki Morokuma, Masaomi Tanaka, Yasuyuki T. Tanaka +80
We present monitoring campaign observations at optical and near-infrared (NIR) wavelengths for a radio-loud active galactic nucleus (AGN) at z=0.840, SDSS~J110006.07+442144.3 (here…
Radio Astrometry towards the Nearby Universe with the SKA
Hiroshi Imai, Ross A. Burns, Yoshiyuki Yamada +5
This chapter summarizes radio astrometry in relation to current very long baseline interferometry (VLBI) projects and describes its perspectives with the SKA. The scientific goals…
Astrometry of HO masers in the massive star--forming region IRAS 06061+2151 with VERA
Kotaro Niinuma, Takumi Nagayama, Tomoya Hirota +8
We measured the trigonometric annual parallax of HO maser source associated with the massive star-forming regions IRAS 06061+2151 with VERA. The annual parallax of $0.496\pm0.0…