459 citations · 1.5k across the 29 of their papers we have counts for
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Testing the External Shock Model of Gamma-Ray Bursts using the Late-Time Simultaneous Optical and X-ray Afterglows
Yuji Urata, Ryo Yamazaki, Takanori Sakamoto +21
We study the ``normal'' decay phase of the X-ray afterglows of gamma-ray bursts (GRBs), which follows the shallow decay phase, using the events simultaneously observed in the R-ban…
The Infrared Cloud Monitor for the MAGNUM Robotic Telescope at Haleakala
M. Suganuma, Y. Kobayashi, N. Okada +6
We present the most successful infrared cloud monitor for a robotic telescope. This system was originally developed for the MAGNUM 2-m telescope, which has been achieving unmanned…
Very early multi-color observations of the plateau phase of GRB 041006 afterglow
Y. Urata, K. Y. Huang, Y. L. Qiu +17
Observations of the optical afterglow of GRB 041006 with the Kiso Observatory 1.05 m Schmidt telescope, the Lulin Observatory 1.0 m telescope and the Xinglong Observatory 0.6 m tel…
Multiple Regression Analysis of the Variable Component in the Near-Infrared Region for Type 1 AGN MCG+08-11-011
Hiroyuki Tomita, Yuzuru Yoshii, Yukiyasu Kobayashi +6
We propose a new method of analysing a variable component for type 1 active galactic nuclei (AGNs) in the near-infrared wavelength region. This analysis uses a multiple regression…
First Detection of Near-Infrared Intraday Variations in the Seyfert 1 Nucleus NGC4395
T. Minezaki, Y. Yoshii, Y. Kobayashi +6
We carried out a one-night optical V and near-infrared JHK monitoring observation of the least luminous Seyfert 1 galaxy, NGC4395, on 2004 May 1, and detected for the first time th…
The Optical/Near-Infrared Light Curves of SN 2002ap for the First 1.5 Years after Discovery
Hiroyuki Tomita, Jinsong Deng, Keiichi Maeda +9
Late-time BVRIJHK photometry of the peculiar Type Ic SN 2002ap, taken between 2002 June 12 and 2003 August 29 with the MAGNUM telescope, is presented. The light curve decline rate…
Reverberation Measurements of the Inner Radius of the Dust Torus in Nearby Seyfert 1 Galaxies
M. Suganuma, Y. Yoshii, Y. Kobayashi +6
The most intense monitoring observations yet made in the optical (UBV) and near-infrared (JHK) wave bands were carried out for nearby Seyfert1 galaxies of NGC 5548, NGC 4051, NGC 3…
Early (0.3 day) R-band light curve of the optical afterglow of GRB030329
Y. Urata, T. Miyata, S. Nishiura +13
We observed the optical afterglow of the bright gamma-ray burst GRB030329 on the nights of 2003 March 29, using the Kiso observatory (the University of Tokyo) 1.05 m Schmidt telesc…
Inner Size of a Dust Torus in the Seyfert 1 Galaxy NGC 4151
T. Minezaki, Y. Yoshii, Y. Kobayashi +5
The most intense monitoring observations yet made were carried out on the Seyfert 1 galaxy NGC 4151 in the optical and near-infrared wave-bands. A lag from the optical light curve…
The Optical/Near-Infrared Light Curves of SN 2002ap for the First 140 Days after Discovery
Y. Yoshii, H. Tomita, Y. Kobayashi +11
Supernova (SN) 2002ap in M74 was observed in the bands for the first 40 days following its discovery (2002 January 29) until it disappeared because of solar conjunction,…
Face-on Barred Spiral Structure of Molecular Clouds in M31's Bulge
Y. Sofue, S. Yoshida, T. Aoki +3
By image processing and color excess analyses of B, V, R, and I-band CCD images of the central region of M31 taken with the Kiso 105-cm Schmidt telescope, we found a bar of 200 pc…