44 citations · 234 across the 11 of their papers we have counts for
11 papers
Subaru Infrared Adaptive Optics-assisted High-spatial-resolution Imaging Search for Luminous Dual Active Galactic Nuclei in Nearby Ultraluminous Infrared Galaxies
Masatoshi Imanishi, Taiki Kawamuro, Satoshi Kikuta +2
We present infrared K'- (2.1 micron) and L'-band (3.8 micron) high-spatial-resolution (<0.3") imaging observations of 17 nearby (z < 0.17) ultraluminous infrared galaxies (ULIRGs)…
Near-infrared Monitoring of the Accretion Outburst in the MYSO S255-NIRS3
Mizuho Uchiyama, Takuya Yamashita, Koichiro Sugiyama +10
We followed-up the massive young stellar object (MYSO) S255-NIRS3 (=S255-IRS1b) during its recent accretion outburst event in the Ks band with Kanata/HONIR for four years after its…
Detection of new methanol maser transitions associated with G358.93-0.03
G. C. MacLeod, K. Sugiyama, T. R. Hunter +18
We report the detection of new 12.178, 12.229, 20.347, and 23.121 GHz methanol masers in the massive star-forming region G358.93-0.03, which are flaring on similarly short timescal…
The shortest periodic and flaring flux variability of a methanol maser emission at 6.7 GHz in G 014.23-00.50
Koichiro Sugiyama, Katsura Nagase, Yoshinori Yonekura +9
We detected flaring flux variability that regularly occurred with the period of 23.9 days on a 6.7 GHz methanol maser emission at Vlsr = 25.30 km/s in G 014.23-00.50 through highly…
Near-Infrared Spectroscopy of Quasars at z~3 and Estimates of Their Supermassive Black Hole Masses
Yuriko Saito, Masatoshi Imanishi, Yosuke Minowa +8
We present the results of new infrared spectroscopic observations of 37 quasars at z~3, selected based on the optical r'-band magnitude and the availability of nearby bright stars…
Near- to Mid- Infrared Imaging and Spectroscopy of Two Buried AGNs of the Nearby Merging Galaxy NGC 6240 with Subaru/IRCS+AO and GTC/CanariCam
Tamami I. Mori, Masatoshi Imanishi, Almudena Alonso-Herrero +7
We report near-infrared K', L', and M' band imaging observations of the nearby merging galaxy NGC 6240 with the Infrared Camera and Spectrograph on the Subaru telescope. The observ…
Relics of Galaxy Merging: Observational Predictions for a Wandering Massive Black Hole and Accompanying Star Cluster in the Halo of M31
Toshihiro Kawaguchi, Yuriko Saito, Yohei Miki +1
Galaxies and massive black holes (BHs) presumably grow via galactic merging events and subsequent BH coalescence. As a case study, we investigate the merging event between the Andr…
Hunting A Wandering Supermassive Black Hole in M31 Halo -- Hermitage of Black Hole
Yohei Miki, Masao Mori, Toshihiro Kawaguchi +1
In the hierarchical structure formation scenario, galaxies enlarge through multiple merging events with less massive galaxies. In addition, the Magorrian relation indicates that al…
Subaru Adaptive-optics High-spatial-resolution Infrared K- and L'-band Imaging Search for Deeply Buried Dual AGNs in Merging Galaxies
Masatoshi Imanishi, Yuriko Saito
We present the results of infrared K- (2.2 micron) and L'-band (3.8 micron) high-spatial-resolution (<0.2 arcsec) imaging observations of nearby gas- and dust-rich infrared luminou…
Observations of 6.7 GHz Methanol Masers with EAVN I: VLBI Images of the first Epoch of Observations
Kenta Fujisawa, Koichiro Sugiyama, Kazuhito Motogi +26
Very long baseline interferometry (VLBI) monitoring of the 6.7 GHz methanol maser allows us to measure the internal proper motions of the maser spots and therefore study the gas mo…
Dense optical and near-infrared monitoring of CTA 102 during high state in 2012 with OISTER: Detection of intra-night "orphan polarized flux flare"
Ryosuke Itoh, Yasushi Fukazawa, Yasuyuki T. Tanaka +35
CTA 102, classified as a flat spectrum radio quasar at z=1.037, produced exceptionally bright optical flare in 2012 September. Following Fermi-LAT detection of enhanced gamma-ray a…