Masaharu Matsuoka
Panasonic
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Publication
Featured researches published by Masaharu Matsuoka.
The Astrophysical Journal | 1987
F. Makino; Yoshitsugu Tanaka; Masaharu Matsuoka; K. Koyama; H. Inoue; Kazumi Makishima; R. Hoshi; Satio Hayakawa; Y. Kondo
Simultaneous multifrequency observations of the BL Lac object Mrk 421 covering radio through X-ray wavelengths were performed on two occasions separated by 5 weeks in January and March 1984, and each observation was coordinated for about 1 week. Composite multifrequency spectra of the central nonthermal component were obtained at the two epochs after subtracting the optical and infrared light of the underlying galaxy. The spectra show the gradual steepening toward high frequency; the power law indices are about 0.1, about 0.6, and about 1.0 for radio, infrared-optical, and UV bands, respectively. The UV and optical-infrared fluxes decreased by about 20 percent in 5 weeks, while the radio flux remained stable. The X-ray flux decreased by a factor of about 2, and the change was more pronounced at hard X-rays, which suggest that X-ray emission possibly consists of two components. The degree of polarization at the optical band varied on the time scale of a few days, while the position angle remained unchanged. Physical parameters of Mrk 421 are discussed in terms of the synchrotron self-Compton model. 55 references.
The Astrophysical Journal | 1984
Masaharu Matsuoka; K. Mitsuda; T. Ohashi; H. Inoue; K. Koyama; F. Makino; Kazumi Makishima; Toshiaki Murakami; M. Oda; Y. Ogawara
Observations of simultaneous optical and X-ray bursts from 4U/MXB 1636-53 were made using the Hakucho burst monitor system and optical telescopes at the European Southern Observatory during 1979 and 1980. The six best cases among the 10 coinciding observations are analyzed in terms of a model in which the optical emission is the result of reprocessing of X-rays (through blackbody heating). From this analysis, the temperature (spatially averaged) and size of a reprocessor, and the smearing and delay of the optical bursts are obtained. For the maximum temperatures of the optical reprocessor, the values differ from burst to burst, ranging from about 3 x 10 to the 4th to about 10 to the 5th K. The present analysis suggests that the size of the reprocessor varies by a factor of a few. For the smearing of the optical bursts an upper limit of a few seconds is derived. The most important result of this analysis is that the delay times are not the same for all bursts. The possible constraints which these results put on a low-mass binary model of this burst source are discussed.
Archive | 2006
Kiyomi Sakamoto; Masaharu Matsuoka; Takanori Morikawa
The Astrophysical Journal | 1984
Yoshio Tawara; Tsuneo Kii; Satio Hayakawa; Hideyo Kunieda; Kazuo Masai; Fumiaki Nagase; H. Inoue; K. Koyama; F. Makino; Kazumi Makishima; Masaharu Matsuoka; Toshiaki Murakami; M. Oda; Y. Ogawara; T. Ohashi; Noriaki Shibazaki; Yoshitsugu Tanaka; Sigenori Miyamoto; Hiroshi Tsunemi; K. Yamashita; Iwao Kondo
The Astrophysical Journal | 1981
Kazumi Makishima; Takehisa Ohashi; Hiroo Inoue; K. Koyama; Masaharu Matsuoka; Toshiaki Murakami; M. Oda; Y. Ogawara; Noriaki Shibazaki; Yoshitsugu Tanaka; Iwao Kondo; Satio Hayakawa; Hideyo Kunieda; F. Makino; Kazuo Masai; Fumiaki Nagase; Yoshio Tawara; Sigenori Miyamoto; Hiroshi Tsunemi; K. da Yamashita
The Astrophysical Journal | 1984
Fumiaki Nagase; Satio Hayakawa; Hideyo Kunieda; Kazuo Masai; N. Sato; Yoshio Tawara; H. Inoue; K. Koyama; F. Makino; Kazumi Makishima; Masaharu Matsuoka; Toshiaki Murakami; M. Oda; Y. Ogawara; T. Ohashi; Noriaki Shibazaki; Yoshitsugu Tanaka; Sigenori Miyamoto; Hiroshi Tsunemi; K. Yamashita; Iwao Kondo
The Japanese Journal of Ergonomics | 2007
Akira Okada; Kuniko Yamashita; Hiroe Ishihara; Kiyomi Sakamoto; Shigeo Asahara; Masaharu Matsuoka; Shoichi Aoyama
The Japanese Journal of Ergonomics | 1997
Mika Mizutani; Masaharu Matsuoka; Akinori Komatsubara
The Japanese Journal of Ergonomics | 2006
Masaharu Matsuoka
The Japanese Journal of Ergonomics | 1999
Akinori Komatsubara; Masaharu Matsuoka; Kazuko Nishida; Naoko Ohnaru