Search

Your search keyword '"Kazumasa Miyano"' showing total 132 results
Start Over Author "Kazumasa Miyano"
132 results on '"Kazumasa Miyano"'

1. Indications of Neutrino Oscillation in a 250 km Long-Baseline Experiment

Author

David William Casper, C. W. Walter, Makoto Sakuda, C. Yanagisawa, Toshio Namba, M. H. Ahn, K. Martens, W. R. Kropp, Nobuyuki Sakurai, H. W. Sobel, S. Fukuda, Atsumu Suzuki, H. Maesaka, Takehisa Hasegawa, T. Iwashita, Minoru Yoshida, Y. Fukuda, S. H. Lim, S. B. Boyd, K. Nishikawa, S. Mine, J. L. Stone, Y. Takeuchi, K. Kaneyuki, Yuichi Oyama, E. Kearns, T. Inagaki, Shinya Yamada, Y. Totsuka, E. J. Jeon, M. Kohama, Shoei Nakayama, Koji Nakamura, S. Matsuno, H. I. Jang, Kazumasa Miyano, J. Hill, C. K. Jung, Masaya Hasegawa, M. Miura, S. B. Kim, Tomoyuki Maruyama, J. H. Choi, D. Kielczewska, Hwangseo Park, I. Kato, John G. Learned, Itsuo Nakano, L. R. Sulak, T. Ishida, A. Obayashi, E. Sharkey, Susumu Noda, H. C. Bhang, T. Ishii, N. Tamura, M. Y. Pac, Yasunari Suzuki, C. O. Kim, N. Sasao, J. S. Jang, H. Yokoyama, W. Gajewski, Kate Scholberg, Ken-ichiro Kobayashi, A. K. Ichikawa, T. Toshito, R. J. Wilkes, Shigetaka Moriyama, A. Kibayashi, J. Y. Kim, I. T. Lim, T. Hara, Shogo Nishiyama, J. Kameda, C. McGrew, M. Ishitsuka, H. So, Shigeki Aoki, J. Yoo, J. Zalipska, Takashi Kobayashi, A. Ikeda, Y. Hayato, A. L. Stachyra, Mark R. Vagins, Masato Shiozawa, Shoji Yamamoto, Tsuyoshi Nakaya, Y. Suga, F. Nakata, Beom Jun Kim, Yoshitaka Itow, Yusuke Koshio, T. Ooyabu, Masayuki Nakahata, Takaaki Kajita, C. Mauger, and A. Okada

Subjects
Physics, Tamura, Norio, Physics::Instrumentation and Detectors, Oscillation, Astrophysics::High Energy Astrophysical Phenomena, Solar neutrino, High Energy Physics::Phenomenology, FOS: Physical sciences, General Physics and Astronomy, Solar neutrino problem, High Energy Physics - Experiment, Nuclear physics, High Energy Physics - Experiment (hep-ex), K2K experiment, Measurements of neutrino speed, High Energy Physics::Experiment, 田村, 詔生, Neutrino, Neutrino oscillation, Charged current
Abstract

The K2K experiment observes indications of neutrino oscillation: a reduction of $\nu_\mu$ flux together with a distortion of the energy spectrum. Fifty-six beam neutrino events are observed in Super-Kamiokande (SK), 250 km from the neutrino production point, with an expectation of $80.1^{+6.2}_{-5.4}$. Twenty-nine one ring $\mu$-like events are used to reconstruct the neutrino energy spectrum, which is better matched to the expected spectrum with neutrino oscillation than without. The probability that the observed flux at SK is explained by statistical fluctuation without neutrino oscillation is less than 1%., Comment: 5 pages, 3 figures embedded, LaTeX with RevTeX style, accepted for publication in PRL on December 13, 2002

Published
2003

2. Observation off2′(1525) Production in HighQ2Two Photon Interactions at TRISTAN

Author

Takashi Sasaki, A. M. Bacala, Richard Lander, Jeffrey Rowe, Satyajit Behari, T. Aso, Tadao Nozaki, A. Abashian, K. Gotow, Y. Fujii, Koji Ueno, Naomi Takashimizu, Shigeo Matsumoto, Hitoshi Miyata, Hiroyuki Sagawa, Soo Kyung Choi, Tsunehiko Omori, Dong Yong Kim, Yoshinobu Takaiwa, Kazumasa Miyano, Y. Sakai, Ho Seok Ahn, Yasuhiro Sugimoto, Susumu Terada, Yousuke Yamashita, C. Rosenfeld, Richard Breedon, Winston Ko, Stephen L. Olsen, A. Murakami, Yoshimasa Kurihara, Moo Hyun Lee, Hong Joo Kim, Miyuki Shirai, Steve Schnetzer, Sun Kee Kim, Leo Piilonen, A. Maki, Kazuo Abe, Shigeharu Kobayashi, Joo Sang Kang, Akinori Kimura, and N. Nakajima

Subjects
Physics, Nuclear physics, Photon, Two-photon excitation microscopy, General Physics and Astronomy, Virtual particle, Resonance (particle physics)
Abstract

We have studied K S 0 K S 0 production in the interactions of a virtual photon ( Q 2 >0) with a real photon and observed the resonance production of f 2 ′ (1525). A total of 5.0±2.2(sta)±0.5(sys) f...

Published
2001

3. Search for Proton Decay throughp→ν¯K+in a Large Water Cherenkov Detector

Author

C. W. Walter, C. Mauger, M. Koshiba, A. Okada, T. Kobayashi, Y. Hatakeyama, K. Nakamura, John G. Learned, T. Futagami, M. R. Vagins, Ko Okumura, J. Hill, V. J. Stenger, S. Kasuga, Y. Fukuda, Yuichi Oyama, G. W. Sullivan, T. Hayakawa, Ken-ichiro Kobayashi, A. T. Suzuki, Masayuki Nakahata, F. Tsushima, Akira Hasegawa, Y. Takeuchi, K. Ishihara, David William Casper, Makoto Sakuda, Kunio Inoue, S. Mine, A. Sakai, Nobuyuki Sakurai, L. R. Price, J. Shirai, Yoshitaka Itow, K. Martens, M. Kirisawa, Hiroshi Ogawa, J. S. George, Y. Kanaya, K. Nishikawa, M. Koike, H. W. Sobel, Yasunari Suzuki, M. Nemoto, J. L. Stone, K. Higuchi, Shigeki Tasaka, E. Sharkey, J. Kameda, S. Hatakeyama, Osamu Sasaki, Takehisa Hasegawa, Y. Watanabe, L. R. Sulak, R. Sanford, S. Inaba, M. B. Smy, Takaaki Kajita, H. Ishino, J. A. Goodman, Kazumasa Miyano, D. Takemori, M. Takahata, Y. Kobayashi, E. Blaufuss, S. Nakayama, K. Kaneyuki, C. Saji, M. Etoh, W. Doki, H. Okazawa, K. S. Ganezer, W. Gajewski, Kate Scholberg, D. Kielczewska, Y. Totsuka, C. McGrew, M. Earl, T. Ishii, Alec Habig, H. Fujiyasu, S. Matsuno, M. Koga, Minoru Yoshida, L. Wai, Tomoyuki Maruyama, T. J. Haines, Y. Obayashi, M. Takita, M. Miura, Takashi Yamaguchi, B. Viren, M. Takahashi, W. R. Kropp, S. Yamada, M. D. Messier, S. Echigo, R. J. Wilkes, K. K. Young, C. Yanagisawa, K. Nishijima, R. W. Ellsworth, A. Kibayashi, Y. Nagashima, H. Takeuchi, B. K. Kim, W. E. Keig, M. L. Chen, M. Goldhaber, Y. Hayato, T. Iwamoto, Yusuke Koshio, S. B. Kim, A. L. Stachyra, M. Kohama, C. K. Jung, Masato Shiozawa, T. Barszczak, E. Kearns, A. Suzuki, R. Svoboda, and Junichi Kanzaki

Subjects
Nuclear physics, Physics, Particle physics, Proton, Proton decay, Cherenkov detector, law, High Energy Physics::Phenomenology, General Physics and Astronomy, High Energy Physics::Experiment, Neutrino, Lower limit, law.invention
Abstract

We present results of a search for proton decays, $p\ensuremath{\rightarrow}\overline{\ensuremath{\nu}}{K}^{+}$, using data from a $33\mathrm{kt}\ifmmode \dot{}\else \.{}\fi{}\mathrm{yr}$ exposure of the Super-Kamiokande detector. Two decay modes of the kaon, ${K}^{+}\ensuremath{\rightarrow}{\ensuremath{\mu}}^{+}{\ensuremath{\nu}}_{\ensuremath{\mu}}$ and ${K}^{+}\ensuremath{\rightarrow}{\ensuremath{\pi}}^{+}{\ensuremath{\pi}}^{0}$, were studied. The data were consistent with the background expected from atmospheric neutrinos; therefore a lower limit on the partial lifetime of the proton $\ensuremath{\tau}/B(p\ensuremath{\rightarrow}\overline{\ensuremath{\nu}}{K}^{+})$ was found to be $6.7\ifmmode\times\else\texttimes\fi{}{10}^{32}\mathrm{years}$ at $90%$ confidence level.

Published
1999

4. Measurement of the Flux and Zenith-Angle Distribution of Upward Throughgoing Muons by Super-Kamiokande

Author

L. R. Price, J. Shirai, E. Sharkey, C. K. Jung, S. Mine, M. Takahata, D. Kielczewska, J. W. Flanagan, Y. Kanaya, Hiroshi Ogawa, Takehisa Hasegawa, Y. Hayato, Y. Watanabe, R. Sanford, J. A. Goodman, Kazumasa Miyano, Minoru Yoshida, H. Okazawa, T. Iwamoto, Ken-ichiro Kobayashi, David William Casper, E. Ichihara, C. W. Walter, Yuichi Oyama, F. Tsushima, Todd Haines, W. Doki, S. Hatakeyama, Takaaki Kajita, H. Ishino, A. Sakai, Yusuke Koshio, L. Wai, Michael B. Smy, Nobuyuki Sakurai, W. E. Keig, Mark R. Vagins, Tomoyuki Maruyama, T. Kobayashi, C. Mauger, Makoto Sakuda, Junichi Kanzaki, K. Nakamura, J. Kameda, B. Viren, M. Miura, Frederick Reines, Ko Okumura, Masatoshi Koshiba, T. Hayakawa, S. Matsuno, T. Ishii, M. D. Messier, Soo-Bong Kim, S. Kasuga, Y. Fukuda, M. Goldhaber, S. Echigo, Yasunari Suzuki, K. Martens, V. J. Stenger, A. Suzuki, R. Svoboda, A. Okada, S. Tasaka, W. R. Kropp, Atsumu Suzuki, A. Kibayashi, Masayuki Nakahata, Y. Totsuka, J. L. Stone, C. Yanagisawa, K. Fujita, E. Kearns, M. L. Chen, W. Gajewski, Kate Scholberg, Kunio Inoue, C. McGrew, K. Ishihara, M. Takita, Y. Takeuchi, K. Kaneyuki, C. Saji, M. Earl, E. Blaufuss, Shinya Yamada, M. Etoh, Masato Shiozawa, K. S. Ganezer, A. L. Stachyra, John G. Learned, Yoshitaka Itow, T. Barszczak, Kyoshi Nishijima, Takashi Yamaguchi, R. W. Ellsworth, R. A. Doyle, T. Futagami, R. J. Wilkes, K. K. Young, Y. Kobayashi, G. W. Sullivan, M. Kohama, Alec Habig, J. S. George, M. Nemoto, L. R. Sulak, M. Koga, H. W. Sobel, Osamu Sasaki, D. Takemori, Shoei Nakayama, K. Nishikawa, J. Hill, Y. Nagashima, B. K. Kim, and Akira Hasegawa

Subjects
Physics, Muon, Astrophysics::High Energy Astrophysical Phenomena, General Physics and Astronomy, Flux, High Energy Physics - Experiment, Nuclear physics, Distribution (mathematics), Angular distribution, Muon flux, High Energy Physics::Experiment, Atomic physics, Super-Kamiokande, Zenith, Energy (signal processing)
Abstract

A total of 614 upward through-going muons of minimum energy 1.6 GeV are observed by Super-Kamiokande during 537 detector live days. The measured muon flux is 1.74+/-0.07(stat.)+/-0.02(sys.)x10^{-13}cm^{-2}s^{-1}sr^{-1} compared to an expected flux of 1.97+/-0.44(theo.)x10^{-13}cm^{-2}s^{-1}sr^{-1}. The absolute measured flux is in agreement with the prediction within the errors. However, the zenith angle dependence of the observed upward through-going muon flux does not agree with no-oscillation predictions. The observed distortion in shape is consistent with the \nu_\mu \nu_\tau oscillation hypothesis with \sin^22\theta > 0.4 and 1x10^{-3} < \Delta m^2 < 1x10^{-1} eV^{2} at 90% confidence level., Comment: 8 pages w/ 3 figures new version contains minor fixes, as it appears in PRL

Published
1999

5. Constraints on Neutrino Oscillation Parameters from the Measurement of Day-Night Solar Neutrino Fluxes at Super-Kamiokande

Author

Frederick Reines, K. Ishihara, T. Kobayashi, Kazumasa Miyano, M. Takita, Atsumu Suzuki, Shoei Nakayama, C. W. Walter, Todd Haines, Y. Totsuka, D. Takemori, E. Kearns, John G. Learned, W. Doki, C. K. Jung, M. Takahata, D. Kielczewska, Takaaki Kajita, H. Ishino, Y. Nagashima, T. Hasagawa, Takashi Yamaguchi, A. Suzuki, V. J. Stenger, C. Mauger, K. Nishikawa, T. Futagami, Y. Kanaya, T. Ishii, M. D. Messier, S. Tasaka, J. S. George, J. Hill, G. W. Sullivan, S. Echigo, R. A. Doyle, B. K. Kim, J. Hsu, K. Kaneyuki, P. G. Halverson, Soo-Bong Kim, M. Goldhaber, C. Saji, S. Kasuga, Y. Fukuda, R. Svoboda, M. Earl, M. Kohama, Minoru Yoshida, J. A. Goodman, W. R. Kropp, L. Wai, A. Okada, Y. Watanabe, R. Sanford, Y. Takeuchi, L. R. Sulak, R. J. Wilkes, Tomoyuki Maruyama, Shinya Yamada, Z. Conner, K. Fujita, K. K. Young, J. L. Stone, H. Okazawa, Y. Hayato, E. Blaufuss, K. Nakamura, David William Casper, C. Yanagisawa, Ken-ichiro Kobayashi, E. Ichihara, T. Iwamoto, H. W. Sobel, Michael B. Smy, S. Mine, A. Sakai, Yoshitaka Itow, M. Miura, Nobuyuki Sakurai, J. W. Flanagan, Yuichi Oyama, Hiroshi Ogawa, Masayuki Nakahata, T. Hayakawa, M. Etoh, A. L. Stachyra, Yusuke Koshio, F. Tsushima, W. E. Keig, Mark R. Vagins, B. Viren, K. S. Ganezer, J. Kameda, Y. Kobayashi, Osamu Sasaki, Masato Shiozawa, M. L. Chen, S. Hatakeyama, W. Gajewski, Kate Scholberg, R. W. Ellsworth, Ko Okumura, T. Barszczak, Masatoshi Koshiba, A. Kibayashi, Kunio Inoue, Kyoshi Nishijima, Makoto Sakuda, K. Martens, Junichi Kanzaki, C. McGrew, S. Matsuno, Yasunari Suzuki, Alec Habig, M. Koga, Akira Hasegawa, L. R. Price, J. Shirai, E. Sharkey, and M. Nemoto

Subjects
Physics, Sterile neutrino, Physics::Instrumentation and Detectors, Solar neutrino, Astrophysics::High Energy Astrophysical Phenomena, High Energy Physics::Phenomenology, General Physics and Astronomy, FOS: Physical sciences, Solar neutrino problem, High Energy Physics - Experiment, Nuclear physics, High Energy Physics - Experiment (hep-ex), Neutrino detector, Measurements of neutrino speed, High Energy Physics::Experiment, Astrophysics::Earth and Planetary Astrophysics, Neutrino, Neutrino oscillation, Super-Kamiokande
Abstract

A search for day-night variations in the solar neutrino flux resulting from neutrino oscillations has been carried out using the 504 day sample of solar neutrino data obtained at Super-Kamiokande. The absence of a significant day-night variation has set an absolute flux independent exclusion region in the two neutrino oscillation parameter space., Comment: 11 pages, 3 figures, submitted to PRL, single-spacing

Published
1999

6. Measurement of the Solar Neutrino Energy Spectrum Using Neutrino-Electron Scattering

Author

L. R. Price, J. Shirai, D. Takemori, J. Hill, Yuichi Oyama, C. Yanagisawa, C. K. Jung, M. Takahata, M. Takita, D. Kielczewska, Y. Totsuka, E. Sharkey, Y. Nagashima, Takaaki Kajita, H. Ishino, W. E. Keig, Mark R. Vagins, C. W. Walter, R. W. Ellsworth, E. Blaufuss, Masatoshi Koshiba, F. Tsushima, M. Earl, Takashi Yamaguchi, A. Kibayashi, T. Ishii, M. D. Messier, B. K. Kim, M. Goldhaber, B. Viren, Yohei Kobayashi, M. Etoh, J. Hsu, S. Echigo, P. G. Halverson, W. R. Kropp, K. S. Ganezer, Makoto Sakuda, K. Nakamura, David William Casper, A. T. Suzuki, R. J. Wilkes, Y. Kanaya, E. Ichihara, Soo-Bong Kim, Y. Hayato, K. Fujita, C. McGrew, E. Kearns, K. K. Young, S. Kasuga, K. Martens, Y. Watanabe, A. Sakai, R. Sanford, Y. Fukuda, Masayuki Nakahata, T. Iwamoto, Y. Takeuchi, Yusuke Koshio, M. Nemoto, H. Okazawa, S. Hatakeyama, Shinya Yamada, Z. Conner, S. Nakayama, K. Kaneyuki, C. Saji, Michael B. Smy, L. R. Sulak, S. Matsuno, Junichi Kanzaki, R. A. Doyle, Yasunari Suzuki, Todd Haines, S. Mine, N. Sakurai, A. L. Stachyra, C. Mauger, Alec Habig, K. Nishikawa, M. Koga, A. Okada, J. W. Flanagan, Masato Shiozawa, M. Kohama, Hiroshi Ogawa, J. L. Stone, T. Barszczak, J. S. George, J. A. Goodman, V. J. Stenger, Takehisa Hasegawa, A. Suzuki, R. Svoboda, Ko Okumura, Kunio Inoue, T. Kobayashi, W. Gajewski, Kate Scholberg, Frederick Reines, K. Ishihara, L. Wai, Tomoyuki Maruyama, H. W. Sobel, Osamu Sasaki, Kyoshi Nishijima, T. Hayakawa, Minoru Yoshida, G. W. Sullivan, John G. Learned, M. Miura, T. Futagami, Ken-ichiro Kobayashi, Yoshitaka Itow, J. Kameda, M. L. Chen, Kazumasa Miyano, W. Doki, S. Tasaka, and Akira Hasegawa

Subjects
Physics, Particle physics, Scattering, Physics::Instrumentation and Detectors, Solar neutrino, General Physics and Astronomy, Solar neutrino problem, High Energy Physics - Experiment, Nuclear physics, Recoil, Neutrino detector, Measurements of neutrino speed, High Energy Physics::Experiment, Neutrino, Neutrino oscillation
Abstract

A measurement of the energy spectrum of recoil electrons from solar neutrino scattering in the Super--Kamiokande detector is presented. The results shown here are obtained from 504 days of data taken between the 31st of May, 1996 and the 25th of March, 1998. The shape of the measured spectrum is compared with the expectation for solar B8 neutrinos. The comparison takes into account both kinematic and detector related effects in the measurement process. The spectral shape comparison between the observation and the expectation gives a chi-square of 25.3 with 15 degrees of freedom, corresponding to a 4.6% confidence level., Comment: 12 pages, 3 figures

Published
1999

7. Calibration of Super-Kamiokande using an electron LINAC

Author

S. Matsuno, Ko Okumura, B. Viren, Akira Hasegawa, L. R. Price, J. Shirai, C. W. Walter, Shigeki Tasaka, E. Sharkey, Hiroshi Ogawa, Takehisa Hasegawa, Y. Nagashima, B. K. Kim, W. R. Kropp, J. A. Goodman, David William Casper, E. Ichihara, Kunio Inoue, Makoto Sakuda, Soo-Bong Kim, S. Kasuga, Y. Fukuda, K. Fujita, A. Sakai, Nobuyuki Sakurai, Y. Hayato, Tomoyuki Maruyama, Takaaki Kajita, H. Ishino, Masatoshi Koshiba, A. Kibayashi, Y. Takeuchi, T. Iwamoto, A. Okada, K. Nishikawa, Shinya Yamada, Y. Totsuka, Yuichi Oyama, C. K. Jung, M. Takahata, T. Ishii, J.W Flanagan, H. Kobayashi, V. J. Stenger, S Mine, Michael B. Smy, D. Kielczewska, Y. Kobayashi, Yusuke Koshio, Z. Conner, Masayuki Nakahata, W. Gajewski, Kate Scholberg, John G. Learned, Atsumu Suzuki, F. Tsushima, A. L. Stachyra, D. Takemori, M. Etoh, E. Kearns, T. Futagami, Alec Habig, Yasunari Suzuki, J. Hsu, M. Earl, M. Koga, L. Wai, Minoru Yoshida, M. Nemoto, Frederick Reines, C. Mauger, M. Goldhaber, K. S. Ganezer, G. W. Sullivan, K. Kaneyuki, C. Saji, Mark R. Vagins, H. Okazawa, E. Blaufuss, Masato Shiozawa, J. S. George, L. R. Sulak, R. A. Doyle, C. Yanagisawa, S. Hatakeyama, T. J. Haines, T. Barszczak, Kyoshi Nishijima, M. Miura, K. Martens, R. W. Ellsworth, Ken-ichiro Kobayashi, Y. Kanaya, J. Kameda, K. Ishihara, T. Hayakawa, M. L. Chen, Y. Watanabe, R. Sanford, M. Kohama, M. Takita, C. McGrew, Shoei Nakayama, J. Hill, J. L. Stone, Koji Nakamura, Takashi Yamaguchi, Junichi Kanzaki, H. W. Sobel, Osamu Sasaki, A. Suzuki, R. Svoboda, T. Kobayashi, P. G. Halverson, R. J. Wilkes, K. K. Young, Yoshitaka Itow, M. D. Messier, S. Echigo, Kazumasa Miyano, W. Doki, and W. E. Keig

Subjects
Physics, Nuclear and High Energy Physics, Physics::Instrumentation and Detectors, Solar neutrino, Detector, Solar neutrino problem, Linear particle accelerator, High Energy Physics - Experiment, Nuclear physics, Neutrino detector, Physics::Accelerator Physics, High Energy Physics::Experiment, Neutrino, Neutrino oscillation, Super-Kamiokande, Instrumentation
Abstract

In order to calibrate the Super-Kamiokande experiment for solar neutrino measurements, a linear accelerator (LINAC) for electrons was installed at the detector. LINAC data were taken at various positions in the detector volume, tracking the detector response in the variables relevant to solar neutrino analysis. In particular, the absolute energy scale is now known with less than 1 percent uncertainty., Comment: 24 pages, 16 figures, Submitted to NIM A

Published
1999

8. An experimental study of the process e+e−→e+e−μ+μ−

Author

R. L. Lander, N. Nakajima, S. K. Choi, C. Rosenfeld, K. Gotow, Takashi Sasaki, H. S. Ahn, P. N. Kirk, Saroj Kumar Sahu, H. Miyata, Y. Yamashita, Y. Sakai, Yuki Fujii, Winston Ko, K. Ueno, S. Behari, A. Murakami, Tsunehiko Omori, L. E. Piilonen, Moo Hyun Lee, A. M. Bacala, Koji Abe, S. Igarashi, T. Aso, Richard Breedon, D. Y. Kim, J. Rowe, M. Sato, Yasuhiro Sugimoto, S. S. Myung, A. Abashian, Hiroyuki Sagawa, A. Kimura, T. Nozaki, J. S. Kang, S. K. Kim, Y. Takaiwa, Hyunyong Kim, S. Kobayashi, Kazumasa Miyano, Naomi Takashimizu, Susumu Terada, Stephen L. Olsen, Yoshimasa Kurihara, M. Shirai, T. J. Wang, Steve Schnetzer, A. Maki, L. Y. Zheng, and S. Matsumoto

Subjects
Nuclear physics, Physics, Nuclear and High Energy Physics, Analytical chemistry, High Energy Physics::Experiment, Luminosity
Abstract

We present the results of a study of e + e − μ + μ − final states produced in e + e − collisions at a center-of-mass energy of 58 GeV using the AMY detector at TRISTAN. The data correspond to a total integrated luminosity of 292.8 pb −1 . The results show good agreement with order α 4 QED predictions.

Published
1998

9. Search for Proton Decay viap→e+π0in a Large Water Cherenkov Detector

Author

A. T. Suzuki, Makoto Sakuda, John G. Learned, T. Futagami, K. Martens, T. Ishizuka, M. Ota, T. Hayakawa, G. W. Sullivan, Yuichi Oyama, Frederick Reines, R. W. Ellsworth, F. Tsushima, K. Ishihara, K. Nakamura, W. Gajewski, Kate Scholberg, T. Kobayashi, E. Ichihara, Y. Kobayashi, Ken-ichiro Kobayashi, H. W. Sobel, M. D. Messier, A. Sakai, B. Viren, M. L. Chen, Y. Nagashima, Junichi Kanzaki, Nobuyuki Sakurai, A. Kusano, T. J. Haines, R. A. Doyle, S. Echigo, H. Koga, Osamu Sasaki, Masayuki Nakahata, Y. Takeuchi, E. Kearns, A. Suzuki, J. Kameda, J. W. Flanagan, P. G. Halverson, W. R. Kropp, Minoru Yoshida, Takaaki Kajita, S. Hatakeyama, M. Goldhaber, Hiroshi Ogawa, R. Svoboda, Z. Conner, J. L. Stone, S. Yamada, K. Fujita, Y. Hayato, Takehisa Hasegawa, J. A. Goodman, Masaki Mori, K. K. Young, Y. Totsuka, T. Iwamoto, M. R. Vagins, M. Kohama, C. Yanagisawa, M. Miura, J. Hsu, C. K. Jung, M. Takahata, T. Kinebuchi, M. Earl, Yusuke Koshio, W. E. Keig, Masato Shiozawa, H. Okazawa, Yoshitaka Itow, J. Wilkes, L. R. Sulak, K. Nishijima, T. Barszczak, C. W. Walter, T. Ishii, J. Hill, A. Kibayashi, M. Takita, M. Oketa, Alec Habig, Tomoyuki Maruyama, D. Takemori, S. Matsuno, M. Koga, A. L. Stachyra, S. Kasuga, Y. Fukuda, C. Mauger, Takashi Yamaguchi, A. Okada, J. S. George, K. Nishikawa, Kazumasa Miyano, S. Nakayama, M. Nemoto, M. Etoh, K. S. Ganezer, S. B. Kim, Akira Hasegawa, L. R. Price, W. Doki, Shigeki Tasaka, E. Sharkey, M. Koshiba, Ko Okumura, Hirokazu Ishino, Kunio Inoue, Yasunari Suzuki, L. Wai, E. Blaufuss, K. Kaneyuki, C. Saji, C. McGrew, V. J. Stenger, Y. Kitaguchi, Y. Kanaya, Y. Watanabe, R. Sanford, and D. Kielczewska

Subjects
Physics, Particle decay, Particle physics, Proton, Cherenkov detector, law, Proton decay, General Physics and Astronomy, Neutrino, Lower limit, law.invention
Abstract

We have searched for proton decay via $p\ensuremath{\rightarrow}{e}^{+}{\ensuremath{\pi}}^{0}$ using data from a $25.5\mathrm{kton}\ifmmode \dot{}\else \.{}\fi{}\mathrm{yr}$ exposure of the Super-Kamiokande detector. We find no candidate events with an expected background induced by atmospheric neutrinos of 0.1 events. From these data, we set a lower limit on the partial lifetime of the proton $\ensuremath{\tau}{/B}_{p\ensuremath{\rightarrow}{e}^{+}{\ensuremath{\pi}}^{0}}$ to be $1.6\ifmmode\times\else\texttimes\fi{}{10}^{33}\mathrm{years}$ at a 90% confidence level.

Published
1998

10. Measurements of the Solar Neutrino Flux from Super-Kamiokande's First 300 Days

Author

T. Hayakawa, R. A. Doyle, T. Yamaguchi, J. A. Goodman, C. McGrew, M. Kohama, Y. Hayato, John G. Learned, T. Futagami, T. Ishizuka, A. T. Suzuki, Masayuki Nakahata, T. Iwamoto, M. Ota, S. Hatakeyama, Yusuke Koshio, R. W. Ellsworth, G. W. Sullivan, Minoru Yoshida, W. E. Keig, Mark R. Vagins, Masatoshi Koshiba, H. Okazawa, H. W. Sobel, Ko Okumura, M. Masuzawa, A. Kibayashi, Y. Totsuka, Osamu Sasaki, J. L. Stone, Yohei Kobayashi, M. Miura, Makoto Sakuda, J. T. Hong, H. Koga, Y. Kitaguchi, Yuichi Oyama, T. Kinebuchi, S. B. Kim, N. Sakurai, Y. Takeuchi, Takaaki Kajita, H. Ishino, M. Goldhaber, Kunio Inoue, Masaki Mori, M. Earl, T. Maruyama, Frederick Reines, T. Ishii, W. R. Kropp, Akira Hasegawa, F. Tsushima, J. Hsu, K. Nakamura, Shinya Yamada, Z. Conner, J. S. George, J. W. Flanagan, Hiroshi Ogawa, K. Kobayashi, Kyoshi Nishijima, S. Nakayama, M. D. Messier, S. Echigo, A. Kusano, S. Matsuno, J. Kameda, Yasunari Suzuki, L. Wai, M. L. Chen, Takehisa Hasegawa, K. Nishikawa, K. Ishihara, M. Takita, P. G. Halverson, Todd Haines, L. R. Price, A. L. Stachyra, D. Takemori, M. Etoh, C. W. Walter, K. Martens, J. Hill, K. S. Ganezer, C. Mauger, Y. Kanaya, E. Sharkey, Y. Watanabe, R. Sanford, B. Viren, A. Okada, M. Nemoto, C. K. Jung, M. Takahata, S. Kasuga, T. Kobayashi, D. Kielczewska, Y. Fukuda, M. Oketa, Kazumasa Miyano, L. R. Sulak, W. Doki, E. Ichihara, W. Gajewski, Kate Scholberg, S. Tasaka, A. Sakai, Yoshitaka Itow, K. Fujita, Alec Habig, M. Koga, Y. Nagashima, A. Suzuki, R. Svoboda, E. Blaufuss, V. J. Stenger, Junichi Kanzaki, Masato Shiozawa, T. Barszczak, E. Kearns, J. Wilkes, K. Kaneyuki, C. Saji, K. K. Young, and C. Yanagisawa

Subjects
Physics, Standard solar model, Particle physics, Solar neutrino, General Physics and Astronomy, Flux, Electron, High Energy Physics - Experiment, Nuclear physics, Constant rate, Recoil, High Energy Physics::Experiment, Astrophysics::Earth and Planetary Astrophysics, Super-Kamiokande, Energy (signal processing)
Abstract

The first results of the solar neutrino flux measurement from Super-Kamiokande are presented. The results shown here are obtained from data taken between the 31st of May, 1996, and the 23rd of June, 1997. Using our measurement of recoil electrons with energies above 6.5 MeV, we infer the total flux of 8B solar neutrinos to be 2.42+-0.06(stat.)+0.10-0.07(syst.)*10^6/cm^2/s. This result is consistent with the Kamiokande measurement and is 36% of the flux predicted by the BP95 solar model. The flux is also measured in 1.5 month subsets and shown to be consistent with a constant rate., Comment: 7 pages, 3 figures

Published
1998

11. Evidence for Oscillation of Atmospheric Neutrinos

Author

Takaaki Kajita, H. Ishino, T. Ishii, T. Kobayashi, Alec Habig, L. Wai, J. Hsu, Tomoyuki Maruyama, Y. Totsuka, M. Koga, Ken-ichiro Kobayashi, Henry W. Sobel, S. Hatakeyama, D. Takemori, Kyoshi Nishijima, V. J. Stenger, M. Earl, Yoshitaka Itow, D. Casper, B. Viren, K. Nakamura, J. Kameda, Makoto Sakuda, A. L. Stachyra, Y. Kanaya, S. Nakayama, W. R. Kropp, N. Sakurai, Masayuki Nakahata, R. A. Doyle, M. Takita, M. L. Chen, S. Matsuno, P. G. Halverson, Akira Hasegawa, K. Martens, K. Fujita, Y. Watanabe, Frederick Reines, R. Sanford, L. R. Price, J. Shirai, W. Gajewski, Kate Scholberg, Osamu Sasaki, M. Kohama, Todd Haines, E. Sharkey, R. J. Wilkes, M. Goldhaber, Takashi Yamaguchi, C. McGrew, Yoshihiro Suzuki, C. Mauger, K. K. Young, S. Mine, C. K. Jung, M. Takahata, D. Kielczewska, J. S. George, Michael B. Smy, E. Ichihara, J. A. Goodman, A. Okada, J. Hill, J. W. Flanagan, Hiroshi Ogawa, M. Nemoto, E. Blaufuss, Kazumasa Miyano, A. T. Suzuki, A. Sakai, Takehisa Hasegawa, M. Etoh, T. Hayakawa, K. Ishihara, K. S. Ganezer, G. W. Sullivan, John G. Learned, H. Okazawa, W. Doki, T. Futagami, T. Barszczxak, R. W. Ellsworth, M. D. Messier, S. Tasaka, Masatoshi Koshiba, S. Echigo, Yuichi Oyama, F. Tsushima, Minoru Yoshida, C. Yanagisawa, A. Kibayashi, Yohei Kobayashi, Y. Nagashima, M. Miura, Ko Okumura, B. K. Kim, Kunio Inoue, K. Nishikawa, A. Suzuki, R. Svoboda, C. W. Walter, Soo-Bong Kim, S. Kasuga, Y. Fukuda, Y. Takeuchi, Shinya Yamada, Z. Conner, Masato Shiozawa, Lawrence Sulak, Junichi Kanzaki, Y. Hayato, T. Iwamoto, Yusuke Koshio, E. Kearns, K. Kaneyuki, C. Saji, J. L. Stone, W. E. Keig, and Mark R. Vagins

Subjects
Physics, Particle physics, Muon, Bilepton, Physics::Instrumentation and Detectors, Astrophysics::High Energy Astrophysical Phenomena, High Energy Physics::Phenomenology, General Physics and Astronomy, Solar neutrino problem, High Energy Physics - Experiment, Nuclear physics, Neutrino detector, K2K experiment, High Energy Physics::Experiment, Neutrino, Neutrino oscillation, Super-Kamiokande
Abstract

We present an analysis of atmospheric neutrino data from a 33.0 kiloton-year (535-day) exposure of the Super-Kamiokande detector. The data exhibit a zenith angle dependent deficit of muon neutrinos which is inconsistent with expectations based on calculations of the atmospheric neutrino flux. Experimental biases and uncertainties in the prediction of neutrino fluxes and cross sections are unable to explain our observation. The data are consistent, however, with two-flavor nu_mu nu_tau oscillations with sin^2(2theta)>0.82 and 5x10^-4 < delta m^2 < 6x10^-3 eV^2 at 90% confidence level., Comment: 9 pages (two-column) with 4 figures. Small corrections to Eqn.4 and Fig.3. Final version to appear in PRL

Published
1998

12. Subthreshold antiproton production in pA, dA and αA reactions

Author

Kazuhiro Tanaka, K. Kimura, H. Ochiishi, Yutaka Yamanoi, J. Chiba, D. Ashery, Tomofumi Nagae, Y. Yoshimura, K. Yasuda, H. Ito, J. Murata, T. Murakami, S. Sawada, Yu. T. Kiselev, S. Kouda, Toshiharu Suzuki, T. Shibata, Michiko Sekimoto, Y. Nakai, Y. Sugaya, Masaharu Numajiri, Kazumasa Miyano, Masaharu Nomachi, and M.K. Vlasov

Subjects
Physics, Nuclear and High Energy Physics, Range (particle radiation), Subthreshold conduction, Nuclear Theory, chemistry.chemical_element, Nuclear physics, Momentum, Deuterium, chemistry, Orders of magnitude (time), Antiproton, High Energy Physics::Experiment, Atomic physics, Nuclear Experiment, Nucleon, Helium
Abstract

An enormous enhancement of antiproton production in deuteron- and α-induced reactions has been observed in the subthreshold energy region between 2 and 5 GeV/nucleon. Antiprotons produced at 5.1° with a momentum range of between 1.0 and 2.5 GeV/ c were measured by a beam-line spectrometer and identified by the time-of-flight method. The production cross sections in the deuteron- and α-induced reactions at an incident energy of 3.5 GeV/nucleon were 2 and 3 orders of magnitude larger than those in proton-induced reaction at the same energy. The enhancement in light-ion reactions could not be explained by the internal motion in the projectile and target nuclei. The target-mass dependence (C, Al, Cu and Pb) of the cross sections has also been studied. Further, the cross sections of π and K productions were measured.

Published
1998

13. Observation of exclusive η production in two photon interactions at TRISTAN

Author

N. Nakajima, Takashi Sasaki, S. S. Myung, Hyunyong Kim, H. Miyata, Y. Yamashita, Y. Sakai, D. Y. Kim, Kazuo Abe, K. Gotow, H. S. Ahn, C. Rosenfeld, A. M. Bacala, M. Shirai, T. J. Wang, J. S. Kang, A. Abashian, Yuki Fujii, R. L. Lander, S. Kobayashi, A. Kimura, Tsunehiko Omori, T. Nozaki, Moo Hyun Lee, K. Ueno, Saroj Kumar Sahu, Richard Breedon, S. K. Choi, Hiroyuki Sagawa, M. Sato, N. Takashimizu, A. Maki, L. Y. Zheng, Winston Ko, S.L. Olsen, P. N. Kirk, T. Aso, L. E. Piilonen, J. Rowe, Yasuhiro Sugimoto, A. Murakami, S. K. Kim, Kazumasa Miyano, Susumu Terada, S. Behari, Yoshimasa Kurihara, Steve Schnetzer, Y. Takaiwa, and S. Matsumoto

Subjects
Nuclear physics, Physics, Nuclear and High Energy Physics, Particle physics, Two-photon excitation microscopy, Astrophysics::High Energy Astrophysical Phenomena, Radiative decay, High Energy Physics::Experiment, Nuclear Experiment, Energy (signal processing)
Abstract

We observe ηc production in the two photon process e+e−→e+e−ηc at an e+e− center-of-mass energy of 58 GeV. We determine the radiative decay width Γγγ(ηc) to be 27±16(sta)±10(sys) keV.

Published
1998

14. Measurement of α using NLLA+O(α2) in e+e− annihilation at =58.0 GeV

Author

Koji Abe, S. S. Myung, S. Behari, H. S. Ahn, Yasuhiro Sugimoto, K. Gotow, Y. Sakai, P. N. Kirk, H. Miyata, Y. Yamashita, Winston Ko, Y. Takaiwa, D. Y. Kim, L. E. Piilonen, A. Abashian, K. Ueno, S. Choi, Hiroyuki Sagawa, N. Takashimizu, Saroj Kumar Sahu, R. L. Lander, J. Rowe, Yoshimasa Kurihara, M. Satou, Tsunehiko Omori, T. Kojima, Steve Schnetzer, C. Rosenfeld, S. K. Choi, N. Nakajima, Takashi Sasaki, Hyunyong Kim, S. Kanda, S. Matsumoto, T. Nozaki, Yuki Fujii, A. Maki, L. Y. Zheng, Richard Breedon, M. Shirai, T. J. Wang, J. S. Kang, S. Kobayashi, Moo Hyun Lee, T. Aso, S. L. Olsen, S. K. Kim, Kazumasa Miyano, Susumu Terada, and A. Murakami

Subjects
Physics, Quantum chromodynamics, Nuclear and High Energy Physics, Particle physics, Annihilation, Astrophysics::High Energy Astrophysical Phenomena, High Energy Physics::Phenomenology, Hadron, Strong coupling, High Energy Physics::Experiment, Jet (particle physics)
Abstract

A measurement of the strong coupling constant αS is presented using hadronic events produced in e+e− annihilations at s =58.0 GeV from the AMY detector at TRISTAN. The measurement is based on comparisons of the distributions of thrust, heavy jet mass, total jet broadening, wide jet broadening, and energy-energy correlations with QCD calculations resummed up to next-to-leading-logarithms matched with the O(αS2) perturbative calculation. Combining the results of the individual evaluations, we find α S (58 GeV )=0.132±0.006 .

Published
1998

15. Large-scale anisotropy of the cosmic-ray muon flux in Kamiokande

Author

Yuichi Oyama, M. Takita, S. Kasuga, Y. Fukuda, A. T. Suzuki, Y. Totsuka, Akito Sakai, H. Okazawa, M. Koshiba, S. Hatakeyama, K. Kihara, T. Kumita, Takayuki Suzuki, T. Horiuchi, E. Ichihara, Yasunari Suzuki, K. Matsumoto, Y. Takeuchi, T. Tomoeda, K. S. Hirata, Ko Okumura, Masayuki Nakahata, T. Yamaguchi, J. Suzuki, Y. Hayato, T. Hara, T. Suda, C. Kato, T. Ishizuka, Yusuke Koshio, Takaaki Kajita, H. Ishino, Kunio Inoue, S. Yasue, Masaki Mori, Toru Tanimori, Kyoshi Nishijima, K. Ishihara, M. Koga, K. Fujita, K. Kaneyuki, K. Nishikawa, S. Miyamoto, Kazuoki Munakata, Kazumasa Miyano, K. Nakamura, T. Hayakawa, S. Joukou, Shigeki Tasaka, T. Kiuchi, Masato Shiozawa, A. Suzuki, Tomoyuki Maruyama, Y. Nagashima, and S. Mori

Subjects
Physics, Astrophysics and Astronomy, Nuclear and High Energy Physics, Particle physics, Muon, Physics::Instrumentation and Detectors, Cherenkov detector, Astrophysics::High Energy Astrophysical Phenomena, Isotropy, Astrophysics::Instrumentation and Methods for Astrophysics, Scale (descriptive set theory), Cosmic ray, Astrophysics, law.invention, Amplitude, law, High Energy Physics::Experiment, Ultra-high-energy cosmic ray, Anisotropy
Abstract

The large-scale anisotropy of cosmic-ray primaries in the celestial coordinate was studied using cosmic-ray muons recorded in a large water Cherenkov detector, Kamiokande. The right-ascension distribution of the muon arrival directions deviated from an isotropic distribution with a 2.8 standard deviation, and agreed well with the first harmonics with an amplitude of $(5.6\ifmmode\pm\else\textpm\fi{}1.9)\ifmmode\times\else\texttimes\fi{}{10}^{\ensuremath{-}4}$ and a phase of $8.0\ifmmode^\circ\else\textdegree\fi{}\ifmmode\pm\else\textpm\fi{}19.1\ifmmode^\circ\else\textdegree\fi{}$. This is the deepest underground observation of the large-scale anisotropy of cosmic rays, and agrees with observations with other underground experiments and extensive air-shower array experiments.

Published
1997

16. A measurement of the photon structure function F2 at Q2 = 6.8 GeV2

Author

Moo Hyun Lee, N. Takashimizu, Kazuo Abe, D. Y. Kim, Winston Ko, K. Gotow, Y. Fujii, Tadao Nozaki, H. S. Ahn, Hiroyuki Sagawa, T. Aso, A. Murakami, Richard Breedon, A. Abashian, S. Matsumoto, Saroj Kumar Sahu, M. Shirai, T. J. Wang, M. Sato, Yasuhiro Sugimoto, A. Maki, L. Y. Zheng, Kazumasa Miyano, S. Behari, Steve Schnetzer, Suyong Choi, Y. Takaiwa, Susumu Terada, K. Ueno, N. Nakajima, Takashi Sasaki, S. S. Myung, R. L. Lander, Stephen L. Olsen, Seong Keun Kim, Yoshimasa Kurihara, J. S. Kang, L. E. Piilonen, J. Rowe, C. Rosenfeld, S. Kobayashi, T. Kojima, H. Miyata, Y. Yamashita, Y. Sakai, Tsunehiko Omori, and P. N. Kirk

Subjects
Nuclear physics, Physics, Quantum chromodynamics, Nuclear and High Energy Physics, Particle physics, law, Detector, Parton, Collider, Value (mathematics), Photon structure function, law.invention
Abstract

The photon structure function F-2(gamma) has been measured at an average Q(2) value of 6.8 GeV2 using data collected by the AMY detector at the TRISTAN e(+)e(-) collider. The measured F-2(gamma) is compared with several QCD-based parton density models. (C) 1997 Published by Elsevier Science B.V.

Published
1997

17. Evaluation of silicon micro strip detectors with large read-out pitch

Author

K. Senyo, Tetsuya Matsuda, Yoshikazu Yamada, Y. Nagashima, Masashi Hazumi, J. Haba, Hitomi Ikeda, H. Miyata, T. Kawasaki, Z. Natkaniec, K. Yamamoto, T. Tsuboyama, Y. Asano, S. Okuno, Chikara Fukunaga, K. Rybicki, H. Palka, M. Rozanska, H. Ozaki, T. Hirose, S. Avrillon, Kazuhisa Yamamura, M. H. Tanaka, H. Iwasaki, A. Bozek, E. Banas, Kazumasa Miyano, and Shigeki Mori

Subjects
Physics, Nuclear and High Energy Physics, Materials science, Silicon, Physics::Instrumentation and Detectors, business.industry, Detector, chemistry.chemical_element, Charge (physics), STRIPS, Capacitance, law.invention, chemistry, law, Aluminium, Optoelectronics, Photonics, business, Image resolution, Instrumentation, Ohmic contact, Voltage
Abstract

For the development of the silicon micro strip detector with the pitch of the readout strips as large as 250 μm on the ohmic side, we made samples with different structures. Charge collection was evaluated to optimize the width of implant strips, aluminum read-out strips, and/or the read-out scheme among strips.

Published
1996

18. Study of neutron background in the atmospheric neutrino sample in Kamiokande

Author

H. Okazawa, Tomoyuki Maruyama, Masaki Mori, S. Kasuga, Y. Fukuda, Y. Totsuka, A. Suzuki, A.T. Suzuki, Toru Tanimori, K. Ishihara, Y. Takeuchi, K. Nishikawa, E. Ichihara, K. S. Hirata, J. Suzuki, Masato Shiozawa, T. Hara, T. Tomoeda, T. Ishizuka, K. Kaneyuki, M. Koshiba, Takaaki Kajita, H. Ishino, A. Sakai, Yuichi Oyama, Masayuki Nakahata, T. Suda, Ko Okumura, Kazumasa Miyano, Kunio Matsumoto, K. Nakamura, Y. Hayato, Kunio Inoue, S. Joukou, K. Fujita, Shigeki Tasaka, Kyoshi Nishijima, T. Hayakawa, Toshiharu Suzuki, Yusuke Koshio, S. Hatakeyama, K. Kihara, T. Kumita, T. Horiuchi, Y. Nagashima, M. Koga, Yasunari Suzuki, M. Takita, Takashi Yamaguchi, and S. Miyamoto

Subjects
Nuclear physics, Physics, Nuclear and High Energy Physics, Neutrino detector, Astrophysics::High Energy Astrophysical Phenomena, Neutron, Atmospheric neutrino, Neutrino, Nuclear Experiment, Neutrino oscillation, Neutron contamination, Sample (graphics)
Abstract

Neutron background in the atmospheric neutrino sample was studied based on the vertex position distribution of the fully contained π 0 events. No evidence for the background contamination was observed. The neutron contamination in the sub-GeV e-like sample was less than 1.2% at 90% C.L.

Published
1996

19. Measurement of the forward-backward asymmetry in ee → b and the b-quark branching ratio to muons at TRISTAN using neural networks

Author

Takashi Sasaki, P. N. Kirk, Hiroyuki Sagawa, Suyong Choi, K. Gotow, Y. Fujii, S. S. Myung, C. Rosenfeld, A. Murakami, M. H. Lee, M. Shirai, Y. Yamashita, S. Igarashi, F. Liu, A. Maki, T. Aso, L. Y. Zheng, K. Ohkubo, S. Kobayashi, D. Y. Kim, S. Behari, Yasuhiro Sugimoto, S. Matsumoto, T. Nozaki, Stephen L. Olsen, H. S. Ahn, N. Takashimizu, Yoshimasa Kurihara, Kazuo Abe, N. Nakajima, S. Kanda, M. Yang, R. L. Lander, S. K. Sahu, Kazumasa Miyano, T. J. Wang, Y. Takaiwa, Steve Schnetzer, H. Fujimoto, Susumu Terada, Winston Ko, Richard Breedon, K. Ueno, M. Sato, Seong Keun Kim, A. Abashian, J. S. Kang, F. Kajino, J. Rowe, Tsunehiko Omori, H. Miyata, Y. Sakai, and L. E. Piilonen

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Muon, Artificial neural network, Branching fraction, media_common.quotation_subject, High Energy Physics::Phenomenology, Forward backward, Asymmetry, Bottom quark, Standard Model, Nuclear physics, High Energy Physics::Experiment, media_common, Bar (unit)
Abstract

The forward-backward asymmetry in e(+)e(-) --> b (b) over bar at root s = 57.9 GeV and the b-quark branching ratio to muons have been measured using neural networks. Unlike previous methods for measuring the b (b) over bar forward-backward asymmetry where the estimated background from c-quark decays and other sources are subtracted, here events are categorized as either b (b) over bar or non-b (b) over bar events by neural networks based on event-by-event characteristics. The determined asymmetry is -0.429 +/- 0.044(stat) +/- 0.047(sys) and is consistent with the prediction of the standard model. The measured B (B) over bar mixing parameter is 0.136 +/- 0.037(stat) +/- 0.040(sys) +/- 0.002(model) and the measured b-quark branching ratio to muons is 0.122 +/- 0.006(stat) +/- 0.007(sys).

Published
1996

20. Measurement of D∗± production in two-photon processes at TRISTAN

Author

Richard Breedon, K. Ueno, Steve Schnetzer, M. Sato, P. N. Kirk, M. H. Lee, S. Matsumoto, K. Gotow, Y. Fujii, L. E. Piilonen, Seong Keun Kim, J. S. Kang, Y. Yamashita, T. Aso, N. Takashimizu, S. S. Myung, H. S. Ahn, Yasuhiro Sugimoto, A. Maki, Takashi Sasaki, C. Rosenfeld, S. Kanda, F. Kajino, A. Murakami, L. Y. Zheng, T. J. Wang, H. Miyata, Kazuo Abe, Y. Sakai, D. Y. Kim, Suyong Choi, Hiroyuki Sagawa, J. Rowe, Winston Ko, Tsunehiko Omori, S. Behari, A. Abashian, Stephen L. Olsen, M. Shirai, Yoshimasa Kurihara, Y. Takaiwa, T. Nozaki, R. L. Lander, K. Ohkubo, F. Liu, N. Nakajima, S. Kobayashi, S. K. Sahu, S. Igarashi, Kazumasa Miyano, and Susumu Terada

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Photon, Luminosity (scattering theory), Meson, High Energy Physics::Phenomenology, Sigma, Vector meson dominance, Jet (particle physics), law.invention, Nuclear physics, law, High Energy Physics::Experiment, Production (computer science), Nuclear Experiment, Collider
Abstract

The inclusive cross section for the production of charmed D*(+/-) mesons in two-photon processes is measured with the AMY detector at the TRISTAN e(+)e(-) collider. D*(+/-) mesons ate identified from the distribution of charged-particle transverse momenta relative to the jet axis. A data sample corresponding to an integrated luminosity of 176 pb(-1) at a center-of-mass energy of 58 GeV is used to determine a cross section sigma(e(+)e(-) --> e(+)e(-)D*(+/-)X) = 270 +/- 49(stat) +/- 38(syst) pb. The results are compared with theoretical expectations based on the Vector Meson Dominance, direct quark-parton model, and resolved photon processes.

Published
1996

21. Observation of the color coherence effect in sub-jet multiplicity of three-jet and four-jet events in e+e− annihilations

Author

L. E. Piilonen, K. Ueno, S. Kanda, M. Yang, J. S. Kang, F. Liu, S. S. Myung, Yasuhiro Sugimoto, N. Takashimizu, S. Behari, S. Kobayashi, Moo Hyun Lee, K. Gotow, Y. Fujii, H. S. Ahn, A. Murakami, Yoshimasa Kurihara, Steve Schnetzer, T. Aso, Hiroyuki Sagawa, H. Miyata, T. Nozaki, Y. Sakai, S.L. Olsen, Y. Takaiwa, D. Y. Kim, A. Abashian, P. N. Kirk, J. Rowe, S. Matsumoto, Tsunehiko Omori, S. K. Sahu, Kazumasa Miyano, Kazuo Abe, Winston Ko, Y. Yamashita, H. Fujimoto, Susumu Terada, Richard Breedon, T. J. Wang, M. Sato, A. Maki, L. Y. Zheng, C. Rosenfeld, S. K. Kim, N. Nakajima, R. L. Lander, Takashi Sasaki, S. K. Choi, K. Ohkubo, and M. Shirai

Subjects
Physics, Nuclear physics, Nuclear and High Energy Physics, Particle physics, Annihilation, Coherence effect, Astrophysics::High Energy Astrophysical Phenomena, Electron–positron annihilation, Monte Carlo method, High Energy Physics::Experiment, Multiplicity (chemistry), Gluon
Abstract

We have measured the ratio of the average sub-jet multiplicity in 3-jet to 2-jet events, R(23), and 4-jet to 2-jet events, R(24), using the e(+)e(-) annihilation data at root s = 58 GeV obtained from the AMY detector. We compare the measured values of R(23) and R(24) With the predictions of coherent and incoherent Monte Carlo models. R(23) is also compared with the NLLA calculations to all-orders. The color coherence effect has been observed to contribute to the suppression of R(23) and R(24) Also, the difference of the behavior between gluon jets in 3-jet and 4-jet events has been studied.

Published
1996

22. A study on the identification capability of a water Čerenkov detector and the atmospheric neutrino problem

Author

Y. Totsuka, H. Okazawa, K. S. Hirata, Akito Sakai, S. Kasuga, K. Nishikawa, T. Hayakawa, T. Kajita, Yusuke Koshio, O. Sasaki, T. Ishizuka, Kazumasa Miyano, Kunio Matsumoto, Masato Shiozawa, Yuichi Oyama, Masayuki Nakahata, K. Fujita, Yasunari Suzuki, K. Kihara, T. Kumita, M. Koga, A. Suzuki, S. Joukou, and Atsumu Suzuki

Subjects
Physics, Nuclear and High Energy Physics, Physics::Instrumentation and Detectors, Cherenkov detector, Solar neutrino, Detector, Proton Synchrotron, Solar neutrino problem, Particle identification, law.invention, Nuclear physics, Neutrino detector, law, Physics::Accelerator Physics, High Energy Physics::Experiment, Neutrino
Abstract

We carried out an experimental test of various characteristics of a water Cerenkov detector, especially the particle identification capability, using the 12-GeV proton synchrotron at KEK, Japan. The detector characteristics so far studied are well reproduced by the Monte Carlo simulation. Especially it is able to identify electrons and muons with mis-identification probabilities less than a few percent in the momentum range of 250–1000 MeV/c except the particle positions in the extreme edge of the detector volume. Based on the present results, the deficiency of μ-neutrinos in the atmospheric neutrinos is not an artifact caused by some peculiar detector characteristics.

Published
1996

23. New limits on the masses of the selectron and photino

Author

Richard Breedon, R. L. Lander, C. Rosenfeld, M. Sato, T. J. Wang, S. K. Sahu, Kazumasa Miyano, L. E. Piilonen, Hiroyuki Sagawa, Y. Fujii, Y. Takaiwa, Tsunehiko Omori, H. Fujimoto, T. Nozaki, S. Behari, Stephen L. Olsen, Susumu Terada, A. Abashian, S. Igarashi, S. S. Myung, J. S. Kang, N. Takashimizu, S. Kobayashi, F. Liu, F. Kajino, Yoshimasa Kurihara, H. Miyata, D. Y. Kim, Y. Sakai, K. Ohkubo, A. Maki, Moo Hyun Lee, M. Shirai, A. Murakami, J. Rowe, L. Y. Zheng, Kazuo Abe, Seong Keun Kim, N. Nakajima, H. S. Ahn, P. N. Kirk, Winston Ko, Y. Yamashita, Takashi Sasaki, Suyong Choi, M. Yang, S. Matsumoto, Steve Schnetzer, S. Kanda, K. Gotow, T. Aso, K. Ueno, and Y. Sugimoto

Subjects
Massless particle, Nuclear physics, Physics, Nuclear and High Energy Physics, Particle physics, Selectron tube, Electron–positron annihilation, Scalar (mathematics), Supersymmetry, Center of mass, Photino, Standard Model
Abstract

A study of e + e − annihilations into final states containing a single energetic photon with no accompanying particles is made at a center of mass energy of 57.8 GeV. The measured cross section is consistent with expectations from standard model processes and is used to set limits on the masses of the scalar electron and photino particles predicted by supersymmetry theories. If the photino is assumed to be massless, the 90% confidence level lower limit on the mass of the degenerate scalar electron is 65.5 GeV. If the results of all the single photon experiments are combined, this lower limit increases to 79.3 GeV.

Published
1996

24. Study of two particle azimuthal correlations ine+e−annihilation at √s=58 GeV

Author

S. Wilson, L. E. Piilonen, Saroj Kumar Sahu, J. Rowe, A. Bodek, C. Rosenfeld, M. E. Mattson, S. Behari, J. S. Kang, Dong-Chul Son, N. Takashimizu, S. K. Choi, K. Ohkubo, Tsunehiko Omori, D. Haim, L. M. Chinitz, K. W. Park, T. Nozaki, Hiroyuki Sagawa, S. Kobayashi, P. N. Kirk, S. Ebara, Moo Hyun Lee, M. Oyoshi, D. Y. Kim, Bj Kim, S. Lusin, Stephen L. Olsen, Y. Yamashita, T. Kumita, Yoshimasa Kurihara, H. Miyata, Takashi Sasaki, R. L. Lander, Y. Sakai, C. P. Cheng, C. A. Fry, Winston Ko, C. Velissaris, D. K. Cho, Yasuhiro Sugimoto, Ryuki Tanaka, Y. Takaiwa, T. Ishizuka, Y. S. Chung, M. H. Ye, F. Liu, A. Abashian, S. K. Kim, F. Kajino, Kazumasa Miyano, Susumu Terada, K. Gotow, Y. Fujii, S. S. Myung, A. Murakami, K. B. Lee, Richard Breedon, T. Aso, S. Kanda, K. Ueno, J. Vinson, J. R. Smith, K. L. Sterner, David Stuart, R. C. Walker, Steve Schnetzer, A. Maki, L. Y. Zheng, Kazuo Abe, M. Shirai, and S. Matsumoto

Subjects
Physics, Particle physics, Annihilation, High Energy Physics::Phenomenology, Hadron, Monte Carlo method, Perturbative QCD, Parton, Hadronization, Gluon, Nuclear physics, High Energy Physics::Experiment, Nuclear Experiment, Event (particle physics)
Abstract

We have measured the azimuthal correlation of hadrons produced in e(+)e(-) annihilations at root s=58 GeV. In perturbative QCD these correlations are sensitive to the interference between soft gluons emitted at large angles with respect to the event axis. However, Monte Carlo calculations incorporating QCD-inspired hadronization models in which the correlation of interjet particles is treated in a phenomenological manner describe the data well. We also observe that angular ordering of the parton showering in the LUND Monte Carlo program improves the agreement with the data.

Published
1995

25. Measurement of charm production in two-photon processes using inclusive lepton events at TRISTAN

Author

L. E. Piilonen, Bj Kim, S. K. Sahu, Kazumasa Miyano, K. Ohkubo, Seong Keun Kim, M. H. Lee, Susumu Terada, K. Gotow, Y. Fujii, M. Oyoshi, N. Nakajima, A. Murakami, P. N. Kirk, T. Aso, S. Behari, H. S. Ahn, Suyong Choi, Takashi Sasaki, R. L. Lander, Y. Yamashita, S. Matsumoto, S. Kobayashi, Kisoo Lee, Kazuo Abe, K. Ueno, Y. Sugimoto, A. Abashian, H. Fujimoto, J. R. Smith, S. Kanda, M. Yang, Winston Ko, Hiroyuki Sagawa, J. Rowe, J. S. Kang, F. Kajino, Tsunehiko Omori, Dong-Chul Son, T. J. Wang, A. Bodek, Ryuki Tanaka, Steve Schnetzer, M. Shirai, Y. Takaiwa, N. Takashimizu, C. Rosenfeld, H. Miyata, Y. Sakai, Stephen L. Olsen, S. S. Myung, A. Maki, L. Y. Zheng, Yoshimasa Kurihara, T. Nozaki, F. Liu, D. Y. Kim, Richard Breedon, and M. Sato

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Luminosity (scattering theory), Muon, High Energy Physics::Phenomenology, Hadron, Electron, Charm quark, Nuclear physics, High Energy Physics::Experiment, Center of mass, Charm (quantum number), Nuclear Experiment, Lepton
Abstract

Measurements of open charm production in photon-photon collisions made with the AMY detector at TRISTAN are reported. Charmed hadrons were identified by detecting the high momentum muons or electrons from their semileptonic decays. The data sample corresponds to an integrated luminosity of 275 pb −1 at an average center of mass energy of 58 GeV. Results are presented in the form of cross sections of inclusive leptons from charm for both muons and electrons. The measured cross section is 1.8 standard deviations higher than theoretical predictions based on the direct and photon-gluon fusion process, where the mass of charm quark is assumed to be 1.6 GeV.

Published
1995

26. A measurement of Bose-Einstein correlations in e+e− annihilation at TRISTAN

Author

M. E. Mattson, H. Miyata, A. Murakami, Kazuo Abe, Hiroyuki Sagawa, K. Ueno, Y. Sugimoto, J. Rowe, A. Bodek, P. N. Kirk, Y. Yamashita, Tsunehiko Omori, Ryuki Tanaka, Y. Takaiwa, T. Nozaki, Bj Kim, S. Matsumoto, C. Rosenfeld, C. A. Fry, J. S. Kang, Stephen L. Olsen, F. Kajino, Yoshimasa Kurihara, F. Liu, M. Oyoshi, K. Gotow, N. Takashimizu, M. Shirai, R. C. Walker, S. S. Myung, T. Aso, Steve Schnetzer, S. Kanda, Richard Breedon, Seong Keun Kim, Saroj Kumar Sahu, Takashi Sasaki, S. Ebara, K. L. Sterner, M. Sato, J. Vinson, Suyong Choi, S. Behari, A. Maki, L. Y. Zheng, R. L. Lander, D. Y. Kim, Moo Hyun Lee, K. Ohkubo, L. E. Piilonen, Winston Ko, C. Velissaris, Kazumasa Miyano, Susumu Terada, N. Nakajima, S. Kobayashi, A. Abashian, Y. Fujii, and Y. Sakai

Subjects
Nuclear physics, Physics, Nuclear and High Energy Physics, Particle physics, Annihilation, law, Track (disk drive), Detector, High Energy Physics::Experiment, Bose–Einstein correlations, Collider, law.invention
Abstract

Using e+e− annihilation events accumulated with the AMY detector at the TRISTAN collider, we have studied the Bose-Einstein correlations in the distributions of like-sign charged tracks. As reference samples we used the opposite-sign charged track pairs and mixed pairs, which are like-sign pairs synthesized from tracks belonging to different events. The results of the different reference samples give approximately 0.45 for the correlation strength and approximately 0.65 fm for the source size. Previous measurements of these parameters in e+e− annihilation at energies from CESR to LEP show remarkably flat dependence on s . Our results conform well with this picture.

Published
1995

27. A determination of α in e+e− annihilation at GeV

Author

J. S. Kang, R. C. Walker, Steve Schnetzer, S. Ebara, N. Takashimizu, K. Gotow, Moo Hyun Lee, P. N. Kirk, Y. Fujii, M. H. Ye, F. Liu, Kazuo Abe, Y. Yamashita, T. Ishizuka, T. Aso, Tsunehiko Omori, David Stuart, Richard Breedon, Y. K. Li, C. A. Fry, S. Lusin, Dong-Chul Son, Ryuki Tanaka, Bj Kim, Takashi Sasaki, K. Ueno, J. Rowe, H. Miyata, Y. Takaiwa, J. Vinson, Y. Sakai, A. Bodek, M. E. Mattson, Robert Stone, A. Murakami, Seong Keun Kim, J. R. Smith, F. Kajino, W. G. Yan, W. X. Gao, D. Y. Kim, T. Thomas, S. S. Myung, C. Velisarris, Hiroyuki Sagawa, S. Matsumoto, T. Nozaki, C. Rosenfeld, A. Maki, L. Y. Zheng, K. L. Sterner, Stephen L. Olsen, M. Oyoshi, A. Abashian, Yoshimasa Kurihara, S. Kobayashi, S. Kanda, R. L. Lander, C. P. Cheng, S. Wilson, Suyong Choi, Kisoo Lee, Saroj Kumar Sahu, Kazumasa Miyano, Yasuhiro Sugimoto, Y. S. Chung, Susumu Terada, R. Poling, S. Behari, T. Kumita, K. W. Park, L. E. Piilonen, L. M. Chinitz, and Winston Ko

Subjects
Quantum chromodynamics, Physics, Nuclear and High Energy Physics, Particle physics, Annihilation, Logarithm, Electron–positron annihilation, High Energy Physics::Phenomenology, Monte Carlo method, Jet (particle physics), Nuclear physics, Strong coupling, High Energy Physics::Experiment, Matrix element
Abstract

We present a study of differential two jet ratios in multi-hadronic final states produced by e(+)e(-) annihilation in the AMY detector at TRISTAN. The data are compared to the predictions of the next-to-leading logarithm parton-shower (NLL PS) Monte Carlo and the O(alpha(s)(2)) matrix element QCD models. We determine the strong coupling strength alpha(s)(57.3 GeV) = 0.130 +/- 0.006.

Published
1995

28. A high-Q2 measurement of the photon structure function F2

Author

N. Takashimizu, T. Nozaki, Bj Kim, N. Nakajima, Dong-Chul Son, K. Gotow, David Stuart, Winston Ko, T. Aso, Saroj Kumar Sahu, S. Behari, Takashi Sasaki, Kazuo Abe, F. Kajino, J. S. Kang, F. Liu, S. Kobayashi, C. Rosenfeld, M. E. Mattson, S. Ebara, Moo Hyun Lee, Richard Breedon, K. Ueno, Y. Sugimoto, K. Ohkubo, S. S. Myung, L. E. Piilonen, P. N. Kirk, Suyong Choi, H. Fujimoto, J. R. Smith, Y. Yamashita, K. L. Sterner, A. Abashian, Y. Sakai, Kisoo Lee, S. Kanda, D. Y. Kim, T. J. Wang, H. Miyata, Y. Fujii, Ryuki Tanaka, Y. Takaiwa, C. Velissaris, M. Oyoshi, R. L. Lander, M. Yang, M. Shirai, Stephen L. Olsen, Yoshimasa Kurihara, A. Maki, A. Murakami, Seong Keun Kim, Tsunehiko Omori, J. Rowe, L. Y. Zheng, S. Matsumoto, A. Bodek, Steve Schnetzer, Kazumasa Miyano, Susumu Terada, Hiroyuki Sagawa, M. Sato, and J. Vinson

Subjects
Momentum, Physics, Nuclear physics, Nuclear and High Energy Physics, Photon, law, Detector, Parton, Atomic physics, Collider, Photon structure function, law.invention
Abstract

The photon structure function F 2 γ has been measured at average Q 2 values of 73 and 390 GeV 2 using data collected by the AMY detector at the TRISTAN e + e − collider. F 2 γ is observed to be increasing as ln Q 2 . The x -dependence of F 2 γ , where x is the momentum fraction carried by the parton inside the photon, is also measured. The measurements are compared with several parton density models.

Published
1995

29. Subthreshold antiproton productions in pA, dA and αA reactions

Author

Yu. T. Kiselev, Y. Sugaya, Masaharu Nomachi, Kazuhiro Tanaka, J. Chiba, Michiko Sekimoto, Y. Yoshimura, H. Ito, K. Kimura, S. Kouda, Y. Nakai, K. Yasuda, T. Murakami, Yutaka Yamanoi, M.K. Vlasov, S. Sawada, D. Ashery, H. Ochiishi, Kazumasa Miyano, Toshiharu Suzuki, and T. Nagae

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Range (particle radiation), Subthreshold conduction, Nuclear Theory, Proton Synchrotron, Ion, Nuclear physics, Antiproton, Physics::Accelerator Physics, Incident energy, High Energy Physics::Experiment, Heavy ion, Nuclear Experiment, Nucleon
Abstract

In April 1994, 4 He ions were accelerated at the KEK proton synchrotron for the first time. Subthreshold antiproton productions with α beams in the incident energy range between 2.0 and 5.0 GeV/nucleon were measured for antiproton momenta between 1.0 and 2.5 GeV/c. The data are compared with the p production cross sections in pA and dA collisions measured previously by our group as well as those in heavy ion collisions.

Published
1995

30. Atmospheric ratio in the multi-GeV energy range

Author

H. Miyata, J. Suzuki, Y. Takeuchi, Kazumasa Miyano, Masaki Mori, K. Nakamura, Y. Nagashima, Akito Sakai, Atsumu Suzuki, E. W. Beier, Masato Shiozawa, Soo-Bong Kim, S. Kasuga, Y. Fukuda, A. T. Suzuki, K. S. Hirata, Toru Tanimori, T. Hara, K. Kaneyuki, E. D. Frank, M. Koga, Takaaki Kajita, M. Koshiba, R. Van Berg, H. Okazawa, T. Ishizuka, Weiya Zhang, S. Joukou, Shigeki Tasaka, Takanori Ishida, Kunio Inoue, K. Kihara, T. Kumita, H. Takei, Yasunari Suzuki, F. M. Newcomer, K. Nishijima, M. Takita, T. Hayakawa, Y. Totsuka, K. Nishikawa, A. Yoshimoto, Yuichi Oyama, Kunio Matsumoto, A.K. Mann, W. Frati, M. Yamada, T. Kajimura, T. Suda, Masayuki Nakahata, Y. Hayato, Yusuke Koshio, and N. Kishi

Subjects
Nuclear physics, Physics, Nuclear and High Energy Physics, Range (particle radiation), Neutrino, Neutrino oscillation, Energy (signal processing)
Abstract

Data from the Kamiokande detector were used to study the atmospheric (v μ + v μ ) (v e + v e ) ratio in the multi-GeV energy range. The observed ratio of μ-like to e-like events relative to the calculated ratio, ( μ /e) data /( μ /e) MC = 0.57 -0.07 +0.08 ± 0.07, suggests that the atmospheric (v μ + v μ ) (v e + v e ) ratio is smaller than expected for these neutrino energies. Also studied was the zenith-angle dependence of the above ratio. Results of an analysis of neutrino oscillations are presented.

Published
1994

31. Measurements of cross section and charge asymmetry for e+e− → μ+μ− and e+e− → τ+τ− at = 57.8

Author

David Stuart, D. Haim, B. J. Kim, C. Rosenfeld, K. Ueno, Y. Sugimoto, J. R. Smith, Kazuo Abe, T. Thomas, Sun Kee Kim, Kisoo Lee, H. Miyata, J. Rowe, M. H. Ye, M. Shirai, A. Bodek, Robert Stone, S. Matsumoto, Yoshimasa Kurihara, Moo Hyun Lee, T. Nozaki, L. M. Chinitz, S. Kobayashi, S. Kanda, F. Kajino, C. A. Fry, Y. Sakai, A. Abashian, C. P. Cheng, Y. K. Li, S. S. Myung, R. C. Walker, Steve Schnetzer, C. Velissaris, Winston Ko, N. Takashimizu, A. Maki, L. Y. Zheng, Dong-Chul Son, K. L. Sterner, Y. Fujii, K. Gotow, S. Wilson, S. L. Olsen, T. Aso, Richard Breedon, T. Kumita, Ryuki Tanaka, Takashi Sasaki, Y. Takaiwa, J. Vinson, M. E. Mattson, T. Ishizuka, A. Murakami, J. S. Kang, F. Liu, T. J. Wang, S. Ebara, D. Y. Kim, Tsunehiko Omori, S. Lusin, P. N. Kirk, Y. Yamashita, K. Ohkubo, M. Oyoshi, R. L. Lander, Kazumasa Miyano, Susumu Terada, K. W. Park, D. K. Cho, L. E. Piilonen, Hiroyuki Sagawa, Suyong Choi, Y. S. Chung, Saroj Kumar Sahu, and S. Behari

Subjects
Physics, Coupling constant, Nuclear and High Energy Physics, Annihilation, Electron–positron annihilation, media_common.quotation_subject, Elementary particle, Charge (physics), Asymmetry, lcsh:QC1-999, Standard Model, Nuclear physics, Cross section (geometry), Atomic physics, lcsh:Physics, media_common
Abstract

With data corresponding to 142 pb−1 accumulated at s = 57.8 GeV by the AMY detector at TRISTAN we measure the cross section of the reactions e+e− → μ+μ− and e+e− → τ+τ− and the symmetry in the angular distributions. For the lowest order cross section we obtain σμμ = 27.54 ± 0.65 ± 0.95 pb and σττ = 28.27 ± 0.87 ± 0.69 pb, and for the forward-backward asymmetry, Aμμ = 0.303 ± 0.027 ± 0.008 and Aττ = −0.291 ± 0.040 ± 0.019. These measurements agree with the standard model. Assuming e−μ−τ univrsality we extract the vector and axial coupling constants | gν| = 0.00 ± 0.09 and |gA| = 0.476 ± 0.024. A fit of data to composite models places lower bounds (95% confidence level) on the compositeness scale of 2–4 TeV.

Published
1994

32. Measurements of cross section and asymmetry fore+e−→bb¯and heavy quark fragmentation at KEK TRISTAN

Author

S. K. Choi, A. Maki, L. Y. Zheng, Hiroyuki Sagawa, M. Oyoshi, Yasuhiro Sugimoto, Y. S. Chung, H. Miyata, R. L. Lander, Y. Sakai, Robert Stone, L. M. Chinitz, S. S. Myung, Bj Kim, S. Kanda, C. Velisarris, M. Shirai, Winston Ko, W. X. Gao, M. H. Ye, Kazuo Abe, J. R. Smith, F. Liu, C. P. Cheng, W. G. Yan, A. Murakami, K. Gotow, Y. Fujii, C. A. Fry, K. W. Park, Stephen L. Olsen, T. Thomas, J. Rowe, A. Bodek, R. Poling, M. E. Mattson, D. K. Cho, Yoshimasa Kurihara, L. E. Piilonen, T. Aso, M. E. Zomorrodian, David Stuart, Dong-Chul Son, K. L. Sterner, M. H. Lee, Kazumasa Miyano, K. Okubo, C. Rosenfeld, P. N. Kirk, S. Matsumoto, Y. Yamashita, Susumu Terada, Ryuki Tanaka, Y. Takaiwa, S. Wilson, Tsunehiko Omori, T. Nozaki, D. Y. Kim, R. C. Walker, A. Abashian, Steve Schnetzer, S. K. Kim, Saroj Kumar Sahu, N. Takashimizu, Takashi Sasaki, F. Kajino, K. B. Lee, Richard Breedon, K. Ueno, J. Vinson, T. Kumita, F. Sannes, Y. K. Li, S. Lusin, J. S. Kang, S. Kobayashi, S. Ebara, and T. Ishizuka

Subjects
Quark, Nuclear physics, Physics, Particle physics, Annihilation, Muon, Meson, Electron–positron annihilation, Hadron, Bottom quark, Charm quark
Abstract

Using 773 muons found in hadronic events from 142 pb-1 of data at a c.m. energy of 57.8 GeV, we extract the cross section and forward-backward charge asymmetry for the e+e- --> bbBAR process, and the heavy quark fragmentation function parameters for the Peterson model. For the analysis of the e+e- --> bbBAR process, we use a method in which the behavior of the c quark and lighter quarks is assumed, with only that of the b quark left indeterminate. The cross section and asymmetry for e+e- --> bbBAR are found to be R(b) = 0.57 +/- 0.06(stat) +/- 0.08(syst) and A(b) = -0.59 +/- 0.09 +/- 0.09, respectively. They are consistent with the standard model predictions. For the study of the fragmentation function we use the variable [x(e)], the fraction of the beam energy carried by the heavy hadrons. We obtain [x(E)]c = 0.56(-0.05-0.03)+0.04+0.03 and [x(E)]b = 0.65(-0.04-0.06)+0.06+0.05, respectively. These are in good agreement with previously measured values.

Published
1994

33. Forward-backward charge asymmetry of quark pairs produced at the KEK TRISTANe+e−collider

Author

K. Gotow, Y. Fujii, Stephen L. Olsen, S. S. Myung, Richard Breedon, J. S. Kang, K. L. Sterner, T. Aso, L. E. Piilonen, Yoshimasa Kurihara, K. Ueno, M. E. Mattson, F. Kajino, M. H. Lee, A. T.M. Wang, J. Vinson, S. Ebara, S. Kanda, S. Wilson, Robert Stone, D. Stuart, Kisoo Lee, C. A. Fry, P. N. Kirk, S. Kobayashi, K. W. Park, C. Velisarris, Sunghee Kim, W. X. Gao, C. Rosenfeld, T. Kumita, Y. Yamashita, C. P. Cheng, Ron Poling, Yasuhiro Sugimoto, T. Ishizuka, Winston Ko, S. K. Choi, F. Sannes, Dong-Chul Son, Hiroyuki Sagawa, T. Thomas, S. Lusin, Bj Kim, D. Haim, Y. S. Chung, J. R. Smith, Takashi Sasaki, M. Oyoshi, J. Rowe, A. Abashian, R. L. Lander, W. G. Yan, A. Maki, A. Bodek, Y. K. Li, L. Y. Zheng, Kazuo Abe, N. Morgan, Saroj Kumar Sahu, L. M. Chinitz, R. C. Walker, Steve Schnetzer, N. Takashimizu, M. H. Ye, F. Liu, Tsunehiko Omori, T. Nozaki, S. Matsumoto, H. Miyata, Y. Sakai, Kazumasa Miyano, Susumu Terada, A. Murakami, Ryuki Tanaka, and Y. Takaiwa

Subjects
Physics, Quark, Particle physics, High Energy Physics::Lattice, Electron–positron annihilation, media_common.quotation_subject, High Energy Physics::Phenomenology, Charge (physics), Jet (particle physics), Asymmetry, law.invention, Standard Model, Nuclear physics, Pair production, law, High Energy Physics::Experiment, Collider, media_common
Abstract

We report on a measurement of the forward-backward charge asymmetry in e+e- --> qqBAR at KEK TRISTAN, where. the asymmetry is near maximum. We sum over all flavors and measure the asymmetry by determining the charge of the quark jets. In addition we exploit flavor dependencies in the jet charge determination to enhance the contributions of certain flavors. This provides a check on the asymmetries of individual flavors. The measurement agrees with the standard model expectations.

Published
1994

34. Measurements of the inclusive jet cross section in photon-photon interactions at TRISTAN

Author

J. R. Smith, S. Lusin, Takashi Sasaki, Saroj Kumar Sahu, S. Behari, Dong-Chul Son, David Stuart, Bj Kim, Stephen L. Olsen, M. H. Lee, Yoshimasa Kurihara, N. Morgan, S. K. Choi, T. Nozaki, C. Velisarris, Sunghee Kim, Kisoo Lee, K. Ohkubo, T. Ishizuka, F. Kajino, A. Maki, L. Y. Zheng, A. Murakami, Robert Stone, M. Shirai, K. Gotow, M. H. Ye, Kazumasa Miyano, Y. Fujii, Kazuo Abe, S. S. Myung, A. Abashian, W. G. Yan, C. Rosenfeld, T. Aso, J. S. Kang, Richard Breedon, K. Ueno, F. Liu, S. Kobayashi, A. Bodek, P. N. Kirk, J. Vinson, M. Oyoshi, Susumu Terada, T. Kumita, W. X. Gao, F. Sannes, S. Ebara, C. P. Cheng, K. L. Sterner, D. Haim, T. Thomas, Winston Ko, Ryuki Tanaka, Y. Takaiwa, S. Kanda, D. Y. Kim, R. L. Lander, D. K. Cho, L. E. Piilonen, C. A. Fry, Y. K. Li, S. Wilson, Y. Yamashita, J. Rowe, S. Matsumoto, R. C. Walker, Steve Schnetzer, N. Takashimizu, K. W. Park, Yasuhiro Sugimoto, M. E. Mattson, Y. S. Chung, L. M. Chinitz, Hiroyuki Sagawa, Tsunehiko Omori, H. Miyata, and Y. Sakai

Subjects
Quantum chromodynamics, Physics, Nuclear and High Energy Physics, Particle physics, Photon, High Energy Physics::Phenomenology, Detector, Physics::Optics, Parton, Jet (particle physics), Photon structure function, Nuclear physics, Cross section (physics), High Energy Physics::Experiment, Perturbation theory (quantum mechanics)
Abstract

We present cross section measurements for inclusive jet production in almost-real photon-photon interactions at TRISTAN using the AMY detector. The results are compared with leading-order QCD calculations for different parameterizations of the parton density in the photon.

Published
1994

35. Double-sided microstrip sensor for the barrel of the SDC silicon tracker

Author

N. Tamura, T. Ohsugi, Kazuhisa Yamamura, S. Kobayashi, Hartmut Sadrozinski, T. Kohriki, Motomasa Daigo, M. Okada, Masato Higuchi, H. Ohyama, Masaharu Muramatsu, K. Yamamoto, Nicolo Cartiglia, Takafumi Ohmoto, T. Aso, Alexander Grillo, Ryuichi Takashima, E. Barberis, H. Miyata, T. Hatakenaka, Fujio Hinode, A. Seiden, Y. Iwata, Yoshinobu Unno, A. Murakami, Kazumasa Miyano, and N. Ujiie

Subjects
Physics, Nuclear and High Energy Physics, Silicon, Physics::Instrumentation and Detectors, business.industry, Detector, chemistry.chemical_element, STRIPS, engineering.material, Microstrip, law.invention, Superconducting Super Collider, Polycrystalline silicon, chemistry, law, engineering, Optoelectronics, Detectors and Experimental Techniques, Photonics, Resistor, business, Instrumentation
Abstract

A full-size prototype microstrip sensor for the silicon tracker of the SDC detector to be used at the Superconducting Super Collider has been fabricated at Hamamatsu Photonics. The sensor is double-sided, using an AC-coupled readout with 50 μm pitch strips. The sensor size is 3.4 × 6.0 cm 2 . Polycrystalline silicon is used as a bias feeding resistor on both surfaces. Each ohmic strip is isolated by a p + blocking line. The detailed requirements for the silicon tracker and the corresponding specifications as well as how to achieve them are discussed. The static performances of this prototype sensor are presented.

Published
1994

36. Measurement of α from the moment of particle momenta within jets from e+e- annihilation

Author

Robert Stone, David Stuart, Kisoo Lee, Kazuo Abe, A. Abashian, Sun Kee Kim, J. R. Smith, F. Sannes, T. Thomas, W. X. Gao, Kazumasa Miyano, B. J. Kim, S. Kanda, R. C. Walker, M. Oyoshi, Steve Schnetzer, Takashi Sasaki, Ko Winston, N. Takashimizu, J. Rowe, M. E. Mattson, Richard Breedon, Dong-Chul Son, L. E. Piilonen, C. Rosenfeld, A. Bodek, W. G. Yan, Yasuhiro Sugimoto, Y. S. Chung, M. H. Ye, Hiroyuki Sagawa, C. Velisarris, S. L. Olsen, R. L. Lander, S. K. Choi, K. Gotow, Y. Fujii, K. Ueno, J. Vinson, Y. K. Li, P. N. Kirk, Susumu Terada, T. Kumita, S. Wilson, D. Haim, N. Morgan, F. Liu, M. E. Zomorrodian, S. Kobayashi, Y. Yamashita, Tsunehiko Omori, Yoshimasa Kurihara, Saroj Kumar Sahu, L. M. Chinitz, C. P. Cheng, T. Nozaki, J. S. Kang, A. Murakami, T. Aso, H. Miyata, C. A. Fry, M. H. Lee, S. Ebara, Y. Sakai, K. W. Park, T. Ishizuka, R. Poling, Ryuki Tanaka, Y. Takaiwa, S. Matsumoto, A. Maki, L. Y. Zheng, F. Kajino, S. S. Myung, K. L. Sterner, and S. Lusin

Subjects
Quantum chromodynamics, Physics, Nuclear and High Energy Physics, Particle physics, Annihilation, Logarithm, Electron–positron annihilation, High Energy Physics::Phenomenology, Jet (particle physics), Nuclear physics, Momentum, Moment (mathematics), Particle, High Energy Physics::Experiment
Abstract

We present a study of the third moment of the inclusive momentum distribution of particles within jets produced by e+e- annihilation at TRISTAN. In this analysis, the QCD coupling strength alpha(s) is determined by fits to the prediction of the Next-to-Leading Logarithm Parton-Shower model. The measured value of alpha(s) (57.9 GeV) = 0.134(-0.005)+0.006.

Published
1993

37. Free-ion yield for tetramethylsilane and tetramethylgermanium

Author

Koji Abe, Kazumasa Miyano, K. Ooyama, M. Neichi, Kazuo Hasegawa, K. Masuda, F. Suekane, H. Yuta, N. Kawamura, K. Suzuki, Masato Higuchi, Ryusaburo Kikuchi, Y. Hoshi, H. Iso, and M. Sakamoto

Subjects
Nuclear and High Energy Physics, Analytical chemistry, Electron, chemistry.chemical_compound, Thermalisation, Distribution function, Nuclear Energy and Engineering, chemistry, Impurity, Yield (chemistry), Electric field, Ionization chamber, Electrical and Electronic Engineering, Atomic physics, Tetramethylsilane
Abstract

Free-ion yields from /sup 207/Bi conversion electrons are measured as a function of applied electric field in an ionization chamber filler with tetramethylsilane (TMS) or tetramethylgermanium (TMG), which are purified by simple methods. The mean thermalization length of electrons liberated in the liquid is calculated by fitting a Gaussian form for the distribution function. The total free-ion yield and thermalization length in TMS and TMG are obtained. They are 3.1+or-0.3, 3.5+or-0.2 and 1.91+or-12 AA, 173+or-16 AA, respectively, including the impurity effect in liquid. >

Published
1993

38. Study of invisible nucleon decay, n→νν, and a forbidden nuclear transition in the Kamiokande detector

Author

Hiroshi Yokoyama, T. Kajumura, K. S. Hirata, Hiroyasu Ejiri, Kazumasa Miyano, A. Suzuki, Nobuaki Sato, Takaaki Kajita, A. Sakai, Toru Tanimori, Takanori Ishida, Kunio Inoue, Y. Fukuda, Miho Yamada, K. Kaneyuki, M. Koshiba, Masayuki Nakahata, E. Kodera, Y. Takeuchi, Y. Oyama, M. Takita, T. Suda, Y. Nagashima, K. Nakamura, Masaki Mori, K. Kihara, Kasuke Takahashi, H. Miyata, Y. Totsuka, A.T. Suzuki, H. Takei, Yasunari Suzuki, and Kyoshi Nishijima

Subjects
Physics, Nuclear physics, Nuclear and High Energy Physics, Range (particle radiation), Branching fraction, Cherenkov detector, law, Detector, Life time, Limit (mathematics), Nucleon, Lower limit, law.invention
Abstract

A search was made for anomalous γ-rays in the energy range 19 and 50 MeV in the large underground water Cherenkov detector Kamiokande. We found no significant excess above the known backgrounds. The result was used to set a limit on invisible nucleon decay through n→ν μ ν μ ν μ , n→ν e ν e ν e and n→ν τ ν τ ν τ . A lower limit on the partial life time τB is given by τB/Br(γ)=1.8×1031 yr(90% CL), where Br(γ)=Γγ/Γtot is the branching fraction of the γ-decay to the particle emission of the deexcitation of 15O∗. The life time limit becomes τB=4.9×1026 yr(90% CL) for a conservative estimate of Br(γ)=2.7×10−5 assuming a nuclear single particle model. The result was also used for studying forbidden transitions in the 16O nucleus. The limit for the relative strength of the forbidden transition to the normal transition is

Published
1993

39. Enhancement of subthreshold antiproton productions in deuteron induced reactions

Author

Yu. T. Kiselev, Masaharu Nomachi, S. Sawada, Y. Yoshimura, T. Nagae, J. Chiba, S. Koda, M.K. Vlasov, Toshio Suzuki, Kazuhiro Tanaka, K. Kimura, Y. Nakai, Kazumasa Miyano, D. Ashery, Michiko Sekimoto, H. Ito, and T. Murakami

Subjects
Nuclear physics, Physics, Nuclear and High Energy Physics, Particle physics, Deuterium, Antiproton, Subthreshold conduction
Abstract

We measured cross sections of subthreshold p productions in the reactions of d + {C, Al, Cu} at 3.0, 3.5, 4.0 and 5.0 GeV/u, and p + {C, Cu} at 3.5, 4.0 and 5.0 GeV. An enormous enhancement of p productions in deuteron induced reactions was found at lower incident energies. It seems to be difficult to understand such an enhancement with our present knowledge of nuclear interactions.

Published
1993

40. Characteristics of an ionization chamber using tetramethylgermanium

Author

Nobuaki Kawamura, F. Suekane, Y. Hasegawa, Kazuo Hasegawa, Y. Iwasaki, H. Hanada, K. Neichi, H. Yuta, J. Katayama, Koji Abe, K. Suzuki, Ryusaburo Kikuchi, K. Ishimaru, Masato Higuchi, M. Kuriki, Kimiaki Masuda, T. Nakajima, Kazumasa Miyano, Y. Hoshi, H. Iso, and M. Sakamoto

Subjects
Physics, Nuclear and High Energy Physics, Yield (engineering), Electron lifetime, macromolecular substances, Radiation, law.invention, Magazine, law, Electrical resistivity and conductivity, Ionization, Ionization chamber, Irradiation, Atomic physics, Instrumentation
Abstract

The material compatibility and the radiation resistivity of liquid tetramethylgermanium have been examined by monitoring the ionization yield and the electron lifetime in a pulse ionization chamber. There is no deterioration of the liquid quality with hardened lead during one year. Irradiation with 1000 Gy of γ-rays causes some deterioration of the liquid. The electron lifetime for the damage liquid was almost restored to its initial value by repeating the purification several times.

Published
1993

41. A limit on massive neutrino dark matter from Kamiokande

Author

Hiroshi Yokoyama, M. Koshiba, T. Suda, Kyoshi Nishijima, Y. Oyama, K. Nakamura, E. W. Beier, Y. Nagashima, Y. Totsuka, K. Kihara, K. S. Hirata, Takanori Ishida, Weiya Zhang, H. Takei, Yasunari Suzuki, Nobuaki Sato, Takaaki Kajita, Mihoko M. Nojiri, W. Frati, Y. Fukuda, Miho Yamada, Soo-Bong Kim, A. Sakai, Masaki Mori, Kazumasa Miyano, E. D. Frank, R. Van Berg, H. Miyata, E. Kodera, Y. Takeuchi, Ken Ichi Hikasa, Masayuki Nakahata, A. Suzuki, F. M. Newcomer, T. Kajimura, A.K. Mann, K. Inoue, K. Takahashi, Toru Tanimori, K. Kaneyuki, and M. Takita

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Large Underground Xenon experiment, Solar neutrino, Astrophysics::Cosmology and Extragalactic Astrophysics, Astrophysics, Solar neutrino problem, Neutrino detector, Warm dark matter, High Energy Physics::Experiment, Neutrino, Neutrino oscillation, Light dark matter
Abstract

We have searched for possible high-energy neutrino signals expected from massive neutrino dark matter captured by the earth and the sun, by making use of upward-going muon samples collected in the seven years of operation of the Kamiokande detector. No excess of events was found from the earth or the sun, thus giving an excluded mass range of Dirac-(Majorana-) type neutrinos, 6 (24) ⩽ m ν ⩽ several hundred GeV, as the dark matter which consitutes the halo of the galaxy. The upper bounds extend to a mass range never before analyzed in previous indirect searches.

Published
1992

42. Survey of atmospheric neutrino data and implications for neutrino mass and mixing

Author

Kasuke Takahashi, Miho Yamada, Toru Tanimori, E. D. Frank, Kazumasa Miyano, Weiya Zhang, A. Suzuki, M. Takita, R. Van Berg, K. Kaneyuki, Y. Takeuchi, W. Frati, M. Koshiba, Nobuaki Sato, Hiroshi Yokoyama, K. Nakamura, Y. Yaginuma, Takaaki Kajita, E. W. Beier, Y. Fukuda, S. Ohara, A. Sakai, T. Kajimura, Masayuki Nakahata, T. Suda, Masaki Mori, H. Miyata, H. Takei, Yasunari Suzuki, K. S. Hirata, Soo-Bong Kim, Yuichi Oyama, E. Kodera, Y. Totsuka, K. Kihara, F. M. Newcomer, K. Inoue, A.K. Mann, Y. Nagashima, Kyoshi Nishijima, Takanori Ishida, and T. Tajima

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Physics::Instrumentation and Detectors, Astrophysics::High Energy Astrophysical Phenomena, Solar neutrino, High Energy Physics::Phenomenology, Solar neutrino problem, Nuclear physics, Neutrino detector, Measurements of neutrino speed, High Energy Physics::Experiment, Neutrino, Neutrino astronomy, Neutrino oscillation, Lepton
Abstract

A detailed comparison is made of the atmospheric neutrino results obtained by the Frejus, IMB-3, and Kamiokande detectors. The implications of these results for vacuum neutrino oscillations are presented, and juxtaposed with the results for matter neutrino oscillations from the solar neutrino data.

Published
1992

43. Observation of a small atmospheric vμ/ve ratio in Kamiokande

Author

K. Nakamura, E. W. Beier, K. S. Hirata, Nobuaki Sato, Takaaki Kajita, E. D. Frank, Y. Takeuchi, Weiya Zhang, M. Koshiba, Hiroshi Yokoyama, Masayuki Nakahata, H. Takei, Yasunari Suzuki, F. M. Newcomer, A. Suzuki, Kunio Inoue, T. Suda, Kasuke Takahashi, Kyoshi Nishijima, Toru Tanimori, Y. Fukuda, Kazumasa Miyano, T. Tajima, A.K. Mann, A. Sakai, Soo-Bong Kim, Y. Yaginuma, H. Miyata, K. Kaneyuki, Y. Totsuka, K. Kihara, Y. Nagashima, Masaki Mori, Takanori Ishida, S. Ohara, M. Takita, E. Kodera, Yuichi Oyama, T. Kajimura, Miho Yamada, R. Van Berg, and W. Frati

Subjects
Physics, Particle scattering, Nuclear physics, Nuclear and High Energy Physics, Particle physics, High Energy Physics::Experiment, Elementary particle, Astrophysics::Earth and Planetary Astrophysics, Neutrino, Atmospheric neutrino, Neutrino oscillation, Flux ratio, Charged current
Abstract

Results are presented of the observation of atmospheric neutrino interactions in the Kamiokande detector in an exposure of 4.92 kt yr. The observed ratio of single ring μ-events to e-events ( μ e ) data ( μ e ) MC = 0.60 +007 −0.06 ( stat. ) ± 0.05 ( syst. ) suggests that the atmospheric vμ/ve ratio is smaller than expected. The implications of these results for neutrino oscillations are discussed.

Published
1992

44. A limit on spontaneous R parity breaking from Kamiokande

Author

T. Suda, Mihoko M. Nojiri, Y. Yaginuma, T. Kajimura, K. S. Hirata, Y. Totsuka, Nobuaki Sato, Kyoshi Nishijima, Takaaki Kajita, Kazumasa Miyano, Masayuki Nakahata, K. Nakamura, Miho Yamada, Y. Nagashima, H. Takei, M. Takita, Masaki Mori, Toru Tanimori, Yasunari Suzuki, Y. Fukuda, K. Kihara, Y. Oyama, K. Kaneyuki, M. Koshiba, T. Tajima, Takanori Ishida, E. Kodera, A. Suzuki, K. Inoue, Kasuke Takahashi, and H. Miyata

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Muon, Physics::Instrumentation and Detectors, High Energy Physics::Phenomenology, Supersymmetry, Nuclear physics, Particle decay, R-parity, Neutralino, High Energy Physics::Experiment, Symmetry breaking, Neutrino, Lepton
Abstract

If R parity is not an exact symmetry in supersymmetric theories, the lightest supersymmetric partner, most favorably the neutralino, would not be stable, but may decay to produce energetic neutrinos. We show that a lack of excess neutrino events above the atmospheric neutrino background, obtained from upward-going muon data in Kamiokande, places a severe constraint on models of R parity breaking if the neutralino is a dark-matter particle.

Published
1992

45. Evidence for hard scattering of hadronic constituents of photons in photon-photon collisions of TRISTAN

Author

Hiroyuki Sagawa, K. Gotow, R. L. Lander, C. Rosenfeld, S. Wilson, Richard Breedon, K. Tomioka, R. C. Walker, Steve Schnetzer, S. S. Myung, L. E. Piilonen, Y. Takaiwa, M. Frautschi, S. Matsumoto, J. Vinson, S. K. Choi, E. H. Low, A. Murakami, F. Sannes, David Stuart, S. Kanda, A. Bacala, K. P. Hu, E. Araki, A. T.M. Wang, T. Nozaki, Y. Oshi, T. Ishizuka, W. G. Yan, H. Kagan, C. P. Cheng, A. Z. Lai, Sun Kee Kim, S. L. Olsen, T. Kumita, Dong-Chul Son, Y. K. Li, C. Velisarris, J. S. Kang, P. N. Kirk, Kazuo Abe, J. Lim, Takashi Sasaki, J. R. Smith, T. Kojima, Yoshimasa Kurihara, Robert Stone, S. Lusin, Tsunehiko Omori, Y. Yamashita, K. Ueno, Yusuke Higashi, Kaori Maeshima, W. X. Gao, P. Gu, M. E. Mattson, H. Miyata, Kazumasa Miyano, C. A. Fry, R. L. Malchow, M. H. Ye, A. Sill, H. Yoshinaka, Yongsun Kim, B. J. Kim, A. Maki, R. D. Kass, Moo Hyun Lee, Winston Ko, S. Kobayashi, Susumu Terada, R. Poling, T. Thomas, D. Blanis, A. Abashian, K. L. Sterner, Rr Mcneil, F. Kajino, R. Tanaka, J. Rowe, A. Bodek, Y. Sakai, Yasuhiro Sugimoto, and Y. Fujii

Subjects
Physics, Nuclear physics, Quantum chromodynamics, Nuclear and High Energy Physics, Particle physics, Photon, Luminosity (scattering theory), Scattering, Nuclear Theory, High Energy Physics::Phenomenology, Hadron, High Energy Physics::Experiment, Nuclear Experiment
Abstract

We present results of an experimental study of e+e−+ hadrons in the kinematic regime for which the process is interpreted as hadron production in collisions of almost-real photons. The data sample corresponds to an integrated luminosity of 27.5 pb− and covers center-of-mass energies from 55 to 61.4 GeV. We observe more events than expected from the incoherent sum of quark-parton and vector-meson-dominance models, and we give a quantitative explanation of the excess by including the hard scattering of the hadronic constituents of the photons calculated with QCD.

Published
1992

46. Search for neutralino dark matter in Kamiokande

Author

Kazumasa Miyano, K. Nakamura, Yuichi Oyama, Y. Totsuka, E. W. Beier, K. S. Hirata, K. Kahara, Weiya Zhang, H. Miyata, M. Koshiba, R. Van Berg, Toru Tanimori, A. Suzuki, K. Kaneyuki, Mihoko M. Nojiri, Soo-Bong Kim, E. Kodera, W. Frati, Nobuaki Sato, Takaaki Kajita, H. Takei, Yasunari Suzuki, F. M. Newcomer, Kyoshi Nishijima, Miho Yamada, Kasuke Takahashi, Y. Fukuda, M. Takita, T. Tajima, Takanori Ishida, Y. Yaginuma, Y. Nagashima, Masaki Mori, A.K. Mann, E. D. Frank, K. Inoue, Masayuki Nakahata, and T. Suda

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Physics::Instrumentation and Detectors, High Energy Physics::Phenomenology, Dark matter, Astrophysics::Cosmology and Extragalactic Astrophysics, Supersymmetry, Astrophysics, Lightest Supersymmetric Particle, Neutralino, Warm dark matter, High Energy Physics::Experiment, Neutrino, Light dark matter, Minimal Supersymmetric Standard Model
Abstract

A search has been made for upward-going muons in the Kamiokande detector as a possible signal from neutralino dark matter captured in the earth. We found the upward-going muon flux from the earth is consistent with that produced by the atmospheric neutrinos. Assuming the galactic halo contains neutralino dark matter, this result provides limits on the neutralino mass in the region 30–80 GeV and gives stringent constraints on the allowed regions of the parameter space in the framework of the minimal supersymmetric standard model.

Published
1991

47. Real-time, directional measurement ofB8solar neutrinos in the Kamiokande II detector

Author

M. Takita, W. Frati, K. Nishijima, Kunio Inoue, F.M. Newcomer, Toru Tanimori, L. R. Feldscher, K. S. Hirata, M. Koshiba, E. Kodera, K. Kaneyuki, K. Nakamura, Y. Yaginuma, Takanori Ishida, Kazumasa Miyano, S. B. Kim, S. Ohara, Y. Nagashima, E. W. Beier, Y. Oyama, Y. Fukuda, Weiya Zhang, A.K. Mann, A. Suzuki, T. Tajima, R. Van Berg, K. Takahashi, Miho Yamada, Masayuki Nakahata, T. Suda, K. Kihara, Y. Totsuka, Masaki Mori, E. D. Frank, H. Takei, Yasunari Suzuki, H. Miyata, Nobuaki Sato, and Takaaki Kajita

Subjects
Physics, Nuclear physics, Standard solar model, Particle physics, Electron energy, Scattering, Solar neutrino, Product (mathematics), High Energy Physics::Experiment, Electron, Neutrino, Recoil electron
Abstract

The method of $^{8}\mathrm{B}$ solar-neutrino measurement by means of the reaction ${\ensuremath{\nu}}_{e}e\ensuremath{\rightarrow}{\ensuremath{\nu}}_{e}e$ in the Kamiokande II detector is described in detail. A data sample of 1040 live detector days in the time period January 1987 through April 1990 yields a clear directional correlation of the solar-neutrino-induced electron events with respect to the Sun and a measurement of the differential electron energy distribution. The measured flux of $^{8}\mathrm{B}$ solar neutrinos from the subsamples of 450 days at electron energy threshold ${E}_{e}\ensuremath{\ge}9.3$ MeV, and 590 days at ${E}_{e}\ensuremath{\ge}7.5$ MeV relative to calculations of the $^{8}\mathrm{B}$ flux based on the standard solar model are 0.46\ifmmode\pm\else\textpm\fi{}0.05(stat)\ifmmode\pm\else\textpm\fi{}0.06(syst) times the prediction of Bahcall and Ulrich, and 0.70\ifmmode\pm\else\textpm\fi{}0.08(stat)\ifmmode\pm\else\textpm\fi{}0.09(syst) times the prediction of Turck-Chi\`eze et al. The shape of the recoil electron energy distribution is consistent with that expected from the product of the known shape of the neutrino flux from $^{8}\mathrm{B}$ $\ensuremath{\beta}$ decay and the cross section for ${\ensuremath{\nu}}_{e}e\ensuremath{\rightarrow}{\ensuremath{\nu}}_{e}e$ scattering. Within the statistical error, there is no evidence in the solar-neutrino signal for a significant time variation.

Published
1991

48. Time Variation of the Cosmic Ray Muon Fluxin Underground Detectors and Correlationwith Atmospheric Temperature

Author

The Matsushiro Collaboration, Kazuoki Munakata, Tomohiro Tsuchida, Shuji Sagisaka, Motoyuki Shimada, Yukihiko Suzuki, Makoto Furuhata, Shinichi Yasue, Satoru Mori, The Kamiokande II Collaboration, Masaki Mori, Yuichi Oyama, Atsuo Suzuki, Kasuke Takahashi, Masashi Yamada, Kazumasa Miyano, Hitoshi Miyata, Hayanori Takei, Keiko S. Hirata, Takaaki Kajita, Ken-ichi Kihara, Masayuki Nakahata, Kenzo Nakamura, Sakuichi Ohara, Nobuaki Sato, Yoichiro Suzuki, Yoji Totsuka, Yoshitomo Yaginuma, Masatoshi Koshiba, Teruhiro Suda, Toshiyuki Tajima, Yoshiyuki Fukuda, Yorikiyo Nagashima, Masato Takita, Kenji Kaneyuki, Toru Tanimori, Eugene W. Beier, Edward D. Frank, William Frati, Soo Bang Kim, Alfred K. Mann, F. Mitchel Newcomer, Richard Van Berg, and Weiping Zhang

Subjects
Physics, Muon, Physics::Instrumentation and Detectors, Astrophysics::High Energy Astrophysical Phenomena, Detector, Astrophysics::Instrumentation and Methods for Astrophysics, General Physics and Astronomy, Cosmic ray, Astrophysics, Atmospheric temperature, Physics::Geophysics, Atmosphere, Observatory, Muon flux, High Energy Physics::Experiment, Variation (astronomy)
Abstract

Time variations of the cosmic ray muon flux observed during the period from January 1987 to April 1990 in the Matsushiro underground muon observatory and the Kamiokande-II detector are compared. A significant correlation between the two observations is found. The observed variations are well explained as a temperature effect in the atmosphere based on precise atmospheric temperature measurements by the Wajima Observatory of the Japan Meteorological Agency.

Published
1991

49. SEARCH FOR CHARGED HEAVY LEPTONS WITH ARBITRARY NEUTRINO MASSES IN e+e− ANNIHILATIONS AT $\sqrt{s} = 50 - 60.8~{\rm GeV}$

Author

Richard Breedon, M. H. Ye, Hiroyuki Sagawa, H. Miyata, J. Vinson, S. Lusin, W. Metcalf, K. Gotow, C. G. Trahern, T. Kumita, David Stuart, Takashi Sasaki, H. S. Budd, Kazuo Abe, C. Rosenfeld, Y. C. Zhu, S. L. Olsen, A. Sill, D. Perticone, F. Sannes, Y. Fujii, J. S. Kang, Y. Sugimoto, T. Mori, R. R. McNeil, Kaori Maeshima, K. Ohta, K. P. Hu, Winston Ko, K. Ueno, F. Kajino, Yasuo Higashi, M. H. Lee, R. Tanaka, E. J. Kim, E. H. Thorndike, J. Lim, G. N. Kim, S. Kobayashi, Robert Stone, J. Li, D. Blanis, Y. Sakai, Y. H. Ho, S.K. Kim, N. M. Shaw, Tsunehiko Omori, P. Gu, I. H. Park, S. Matsumoto, J. Liu, T. Nozaki, R. L. Malchow, P. Auchincloss, K. L. Sterner, Bj Kim, R. L. Imlay, D. H. Han, Yongsun Kim, J. Rowe, T. Ishizuka, R. D. Kass, K. Tomioka, A. Maki, C. P. Cheng, A. Bodek, C. A. Fry, S. S. Myung, H. W. Zheng, R. C. Walker, A. Bacala, Steve Schnetzer, H. Harada, Y. Takaiwa, Dong-Chul Son, H. Kagan, C. Velissaris, M. E. Mattson, A. Abashian, Y. Ishi, Yoshimasa Kurihara, E. H. Low, S. Wilson, P. N. Kirk, R. L. Lander, Y. Yamashita, Y. K. Li, A. Murakami, M. Frautschi, R. Poling, Kazumasa Miyano, Sarah Catherine Eno, Susumu Terada, T. Thomas, A. T.M. Wang, J. R. Smith, Hyunyong Kim, and L. E. Piilonen

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, High Energy Physics::Phenomenology, Hadron, Astronomy and Astrophysics, Atomic and Molecular Physics, and Optics, Massless particle, Nuclear physics, Pair production, High Energy Physics::Experiment, Neutrino, Nuclear Experiment, Lepton
Abstract

Results of a search for the pair production of charged heavy leptons in e+e− annihilations over the center-of-mass energy range of 50 to 60.8 GeV are reported. We assume that the leptons are of the sequential type but have allowed for the case where the associated neutrino might be massive. Separate searches for evidence for decays to hadronic and leptonic final states, searches specialized for the case where the charged lepton and its associated neutrino are close in mass, and a search for stable heavy leptons have uncovered no evidence for the production of such particles at these energies. Mass limits for heavy leptons and their associated neutrinos are determined for a range of hadronic and leptonic decay branching fractions. A sequential charged heavy lepton with mass between 12.6 and 29.6 GeV/c2 and with massless neutrino is excluded at the 95% confidence level.

Published
1991

50. A measurement of the photon structure function F2

Author

J. Rowe, A. Bodek, Richard Breedon, T. Kumita, Y. Sugimoto, E. H. Low, Robert Stone, David Stuart, S. Kanda, M. E. Mattson, T. Nozaki, H. Kagan, J. S. Kang, Y. Ishi, C. Velisarris, E. J. Kim, Takashi Sasaki, Kazumasa Miyano, A. Murakami, Yusuke Higashi, K. Ueno, J. Vinson, L. E. Piilonen, J. R. Smith, P. N. Kirk, T. Kojima, T. Yasuda, Y. C. Zhu, Y. Yamashita, Kazuo Abe, S. L. Olsen, C. A. Fry, K. Gotow, S. K. Choi, M. H. Ye, N. M. Shaw, R. L. Malchow, H. Miyata, E. H. Thorndike, Hiroyuki Sagawa, C. P. Cheng, J. Lim, Kaori Maeshima, Yongsun Kim, A. T.M. Wang, M. Frautschi, W. Metcalf, Y. Yamagishi, H. Harada, R. D. Kass, B. J. Kim, Y. Takaiwa, Sarah Catherine Eno, P. Gu, Susumu Terada, A. Bacala, H. S. Budd, C. Rosenfeld, T. Ishizuka, A. Sill, R. L. Lander, Dong-Chul Son, Tsunehiko Omori, Yoshimasa Kurihara, S. Matsumoto, S. S. Myung, H. W. Zheng, Moo Hyun Lee, K. Ohta, S. Schenetzer, Winston Ko, P. Auchincloss, S. Kobayashi, F. Sannes, Y. H. Ho, Hyunyong Kim, K. P. Hu, D. H. Han, A. Maki, G. N. Kim, Y. K. Li, S. Lusin, S. Wilson, R. Poling, R. C. Walker, D. Blanis, R. Tanaka, K. L. Sterner, A. Z. Lai, Rr Mcneil, S. K. Kim, F. Kajino, Y. Fujii, Y. Sakai, T. Thomas, and A. Abashian

Subjects
Quantum chromodynamics, Nuclear physics, Physics, Nuclear and High Energy Physics, Particle physics, Structure function, Range (statistics), High Energy Physics::Experiment, Photon structure function
Abstract

The photon structure function F2 has been measured at average Q2 values of 73,160 and 390 ( GeV c ) 2 . We compare the x dependence of the Q2 = 73 ( GeV c ) 2 data with theoretical expectations based on QCD. In addition we present results on the Q2 evolution of the structure function for the intermediate x range (0.3⩽ x ⩽0.8). The results are consistent with QCD.

Published
1990

Catalog

Books, media, physical & digital resources
See catalog results