Early phase observations of extremely luminous Type Ia Supernova 2009dc (2009)
Yamanaka, M., Kawabata, K. S., Kinugasa, K., Tanaka, M., Imada, A., Maeda, K., ...
We present early phase observations in optical and near-infrared wavelengths for the extremely luminous Type Ia supernova (SN Ia) 2009dc. The decline rate of the light curve is $\Delta...
Doppler-Broadened Iron X-ray Lines from Tycho's Supernova Remnant (2009)
Furuzawa, A., Ueno, D., Hayato, A., Ozawa, M., Tamagawa, T., Bamba, A., ...
We use \suzaku observations to measure the spatial variation of the Fe K$\alpha$ line with radius in the \tycho supernova remnant. The Fe line widths show a significant decrease from a FWHM value of...
Spectroscopic Observations of WZ Sge-type Dwarf Novae, GW Lib and V455 And in Superoutburst (2008)
Nogami, D., Hiroi, K., Suzuki, Y., Moritani, Y., Soejima, Y., Imada, A., ...
We carried out intensive spectroscopic observations of two WZ Sge-type dwarf novae, GW Lib, and V455 And during their superoutbursts in 2007, at 6 observatories. The observations covered the whole of...
Suzaku Observations of Tycho's Supernova Remnant (2008)
Tamagawa, T., Hayato, A., Nakamura, S., Terada, Y., Bamba, A., Hiraga, J. S., ...
Tycho's supernova remnant was observed by the XIS and HXD instruments onboard the Suzaku satellite on 2006 June 26-29 for 92 ks. The spectrum up to 30 keV was well fitted with a two-component model,...
Fukui, A., Abe, F., Ayani, K., Fujii, M., Iizuka, R., Itow, Y., ...
We report the observation of the first gravitational microlensing event in a sparse stellar field, involving the brightest (V=11.4 mag) andclosest (~ 1 kpc) source star to date. This event was...
Observation Campaign of SS 433 in April 2006 (2006)
Kotani, T., Kubota, K., Namiki, M., Kawai, N., Ueda, Y., Trushkin, S., ...
A radio-IR-optical-X-ray observation campaign of SS 433 has been performed in April 2006, when the jet axis is almost perpendicular to the line of sight. Five flares have been detected during the...
Swift and Suzaku Observations of the X-Ray Afterglow from the GRB 060105 (2006)
Tashiro, M. S., Abe, K., Angelini, L., Barthelmy, S., Gehrels, N., Ishikawa, N., ...
Results are presented of early X-ray afterglow observations of GRB 060105 by Swift and Suzaku. The bright, long gamma-ray burst GRB 060105 triggered the Swift Burst Alert Telescope (BAT) at 06:49:28...
A Massive Jet Ejection Event from the Microquasar SS 433 Accompanying Rapid X-Ray Variability (2005)
Kotani, T., Trushkin, S. A., Valiullin, R., Kinugasa, K., Safi-Harb, S., Kawai, N., ...
Microquasars occasionally exhibit massive jet ejections which are distinct from the continuous or quasi-continuous weak jet ejections. Because those massive jet ejections are rare and short events,...
Nysewander, M. C., Reichart, D. E., Williams, G. G., Kinugasa, K., Lamb, D. Q., ...
We present Follow-Up Network for Gamma-Ray Bursts (FUN GRB) Collaboration observations of the optical afterglow of GRB 021211 made between 143 seconds and 102 days after the burst. Our unique data...
2MASS J0516288+260738: Discovery of the first eclipsing late K + Brown dwarf binary system (2003)
Schuh, S.L., Handler, G., Drechsel, H., Hauschildt, P., Dreizler, S., Medupe, R., ...
The Earliest Optical Observations of GRB 030329 (2003)
Torii, K., Kato, T., Yamaoka, H., Kohmura, T., Okamoto, Y., Ohnishi, K., ...
We present the earliest optical imaging observations of GRB 030329 related to SN 2003dh. The burst was detected by the HETE-2 satellite at 2003 March 29, 11:37:14.67 UT. Our wide-field monitoring...
2MASSJ0516288+260738: Discovery of the first eclipsing late K + Brown dwarf system? (2003)
Schuh, S. L., Handler, G., Drechsel, H., Hauschildt, P. H., Dreizler, S., Medupe, R., ...
We report the discovery of a new eclipsing system less than one arcminute south of the pulsating DB white dwarf KUV 05134+2605. The object could be identified with the point source...
Period change of Superhumps in the WZ Sge-Type Dwarf Nova, HV Virginis (2003)
Ishioka, R., Kato, T., Uemura, M., Pietz, J., Vanmunster, T., Krajci, T., ...
After 10 years of quiescence, HV Vir underwent a superoutburst in January 2002. We report time-series observations clearly revealing the period change of ordinary superhumps during the superoutburst....
Early-Phase Spectra of "Hypernova" SN 2002ap (2002)
Kinugasa, K., Kawakita, H., Ayani, K., Kawabata, T., Yamaoka, H., Deng, J. S., ...
The spectral evolution of the peculiar SN Ic 2002ap during the first 40 days is presented. The spectra display very broad absorption features, which are typical of "hypernovae". The maximum expansion...
A Massive Jet-Ejection from SS433 (2002)
Kotani, T., Trushkin, S., Denissyuk, E. K., Kawakita, N., Kinugasa, K., Safi-Harb, S., ...
The detection of a massive jet-ejection event from SS433 with RXTE is reported. SS433 in its high state has been monitored with RXTE from 2001/11/09 (MJD = 52222) to 2001/11/25 (MJD = 52238),...
The Type Ic Hypernova SN 2002ap (2002)
Mazzali, P. A., Deng, J., Maeda, K., Nomoto, K., Umeda, H., Hatano, K., ...
Photometric and spectroscopic data of the energetic Type Ic supernova (SN) 2002ap are presented, and the properties of the SN are investigated through models of its spectral evolution and its light...
Discovery of a new pulsating X-ray source with a 1549.1-s period, AX J183220-0840 (2000)
Sugizaki, M., Kinugasa, K., Matsuzaki, K., Terada, Y., Yamauchi, S., Yokogawa, J.
A new pulsating X-ray source, AX J183220-0840, with a 1549.1-s period was discovered at R.A.= 18h32m20s and Dec.=-8d40'30'' (J2000, uncertainty=0.6degree) during an ASCA observation on the Galactic...
A Giant Glitch in the Energetic 69 ms X-ray Pulsar AXS J161730-505505 (2000)
Torii, K., Gotthelf, E. V., Vasisht, G., Dotani, T., Kinugasa, K.
We present new results on the recently discovered 69 ms X-ray pulsar AXS J161730-505505, the sixth youngest sample of all known pulsars. We have undertaken a comprehensive X-ray observing campaign of...