42 citations · 281 across the 16 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…
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…
Extensive multiband study of the X-ray rich GRB 050408. A likely off-axis event with an intense energy injection
A de Ugarte Postigo, T. A. Fatkhullin, G. Johannesson +40
Aims. Understand the shape and implications of the multiband light curve of GRB 050408, an X-ray rich (XRR) burst. Methods. We present a multiband optical light curve, covering the…
Multi-color Shallow Decay and Chromatic Breaks in the GRB 050319 Optical Afterglow
K. Y. Huang, Y. Urata, P. H. Kuo +19
Multi-wavelength B, V, R, I observations of the optical afterglow of GRB 050319 were performed by the 1.05-m telescope at Kiso Observatory and the 1.0-m telescope at Lulin Observat…
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…
Multi-band optical follow-up observations of GRB 020813 at KISO and Bisei observatories
Y. Urata, S. Nishiura, T. Miyata +9
Observations were made of the optical afterglow of GRB020813 (Fox, Blake & Price, 2002) with the KISO observatory 1.05 m Schmidt telescope and the Bisei astronomical observatory 1.…