126 citations · 392 across the 12 of their papers we have counts for
12 papers
A Giant Metrewave Radio Telescope Survey of Radio-loud Broad Absorption Line Quasars
Takayuki J. Hayashi, Akihiro Doi, Hiroshi Nagai
A substantial fraction of quasars display broad absorption lines (BALs) in their rest-frame ultraviolet spectra. While the origin of BALs is thought to be related to the accretion…
ALMA Confirmation of Millimeter Time Variability in the Gamma-Ray Detected Seyfert Galaxy GRS 1734-292
Tomonari Michiyama, Yoshiyuki Inoue, Akihiro Doi +4
GRS 1734-292 is a radio-quiet galaxy, exhibiting neither intense starburst nor jet activities. However, Fermi-LAT detected this object in the GeV band. The origin of non-thermal ac…
Discovery of off-axis jet structure of TeV blazar Mrk 501 with mm-VLBI
S. Koyama, M. Kino, M. Giroletti +10
High-resolution millimeter wave very-long-baseline interferometry (mm-VLBI) is an ideal tool for probing the structure at the base of extragalactic jets in detail. The TeV blazar M…
Fermi-LAT and Multi-wavelength Monitoring of the Broad Line Radio Galaxy 3C 120
Y. T. Tanaka, A. Doi, Y. Inoue +7
We present six-year multi-wavelength monitoring result for broad-line radio galaxy 3C 120. The source was sporadically detected by Fermi-LAT and after the MeV/GeV gamma-ray detecti…
Probing Precise Location of Radio Core in TeV Blazar Mrk 501 with VERA at 43 GHz
S. Koyama, M. Kino, A. Doi +13
We investigate the position of the radio core in a blazar by multi-epoch astrometric observations at 43 GHz. Using the VLBI Exploration of Radio Astrometry (VERA), we have conducte…
Six Years of Fermi-LAT and Multi-wavelength Monitoring of the Broad-Line Radio Galaxy 3C 120: Jet Dissipation at Sub-parsec Scales from the Central Engine
Y. T. Tanaka, A. Doi, Y. Inoue +7
We present multi-wavelength monitoring results for the broad-line radio galaxy 3C 120 in the MeV/GeV, sub-millimeter, and 43 GHz bands over six years. Over the past two years, Ferm…
A strong radio brightening at the jet base of M87 during the elevated very-high-energy gamma-ray state in 2012
K. Hada, M. Giroletti, M. Kino +18
The nearby radio galaxy M87 offers a unique opportunity for exploring the connection between gamma-ray production and jet formation at an unprecedented linear resolution. However,…
A strong radio brightening at the jet base of M87 during the elevated very-high-energy gamma-ray state in 2012
K. Hada, M. Giroletti, M. Kino +18
We report our intensive radio monitoring observations of the jet in M87 with the VLBI Exploration of Radio Astrometry (VERA) and the European VLBI Network (EVN) from February 2011…
Limb-Brightened Jet of 3C 84 Revealed by the 43-GHz Very-Long-Baseline-Array Observation
H. Nagai, T. Haga, G. Giovannini +8
We present a study of sub-pc scale radio structure of the radio galaxy 3C 84/NGC 1275 based on the Very Long Baseline Array (VLBA) data at 43 GHz. We discover a limb-brightening in…
The ordinary life of the gamma-ray emitting narrow-line Seyfert 1 galaxy PKS 1502+036
F. D'Ammando, M. Orienti, A. Doi +7
We report on multifrequency observations of the gamma-ray emitting narrow-line Seyfert 1 galaxy PKS 1502+036 performed from radio to gamma-rays during 2008 August-2012 November by…
Physical properties of the nuclear region in Seyfert galaxies derived from observations with the European VLBI Network
P. Bontempi, M. Giroletti, F. Panessa +2
We report on sensitive dual-frequency (1.7 and 5 GHz) European VLBI Network observations of the central region of nine Seyfert galaxies. These sources are among the faintest and le…
The kinematic of HST-1 in the jet of M87
M. Giroletti, K. Hada, G. Giovannini +9
Aims: We aim to constrain the structural variations within the HST-1 region downstream of the radio jet of M87, in general as well as in connection to the episodes of activity at v…