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1. The Super-Kamiokande detector

Author

Kimihiro Okumura, Makoto Sakuda, B. K. Kim, S. Fukuda, K. Martens, S. Moriyama, Toshio Suzuki, Todd Haines, S. B. Boyd, M. L. Chen, T. Hasegawa, Z. Conner, M. Kitaguchi, K. Nishikawa, K. S. Ganezer, Alec Habig, M. Earl, B. Viren, J. Kameda, M. Koga, H. Okazawa, R. W. Ellsworth, A. Okada, M. Takahashi, J. S. George, K. Ishihara, Atsumu Suzuki, T. Inagaki, Shoichi Yamada, Takaaki Kajita, S. Matsuno, T. Iwashita, K. Fujita, H. G. Berns, M. Ishitsuka, S. Desai, Koji Nakamura, M. Miura, Y. Ichikawa, Mikio Morii, E. Guillian, C. K. Jung, M. Takahata, H. Nishihama, J. Hsu, K. Ito, Toshio Namba, D. Kielczewska, T. Ishii, Kunio Inoue, S. Nakayama, John G. Learned, I. Kato, M. Etoh, I. Nishiyama, T. Futagami, A. L. Stachyra, K. Miyano, C. Saji, Y. Hatakeyama, T. Hayakawa, H. Maesaka, R. A. Doyle, Florian Goebel, M. B. Smy, J. L. Stone, D. W. Liu, David William Casper, E. Ichihara, T. Hashimoto, A. K. Ichikawa, C. Yanagisawa, K. Nishijima, S. Hatakeyama, M. Kohama, Akira Hasegawa, G. W. Sullivan, Henry W. Sobel, K. Nitta, Y. Kobayashi, A. Sakai, M. Takita, M. Ackerman, Frederick Reines, L. R. Price, J. Shirai, W. Wang, T. Horiuchi, H. Takeda, V. J. Stenger, M. Masuzawa, E. Sharkey, Minoru Yoshida, Yoshitaka Itow, D. Turcan, S. Inaba, N. Sakurai, T. Takayama, Y. Kanaya, M. Kirisawa, R. Svoboda, M. Koike, J. Hill, Shuji Yamamoto, A. Kusano, K. Higuchi, Hiroaki Nishimura, Masaya Hasegawa, Y. Watanabe, K. Kaneyuki, T. Kobayashi, R. Sanford, Osamu Sasaki, Magdalena Malek, Y. Kajiyama, A. Kibayashi, L. R. Sulak, W. Doki, S. Tasaka, T. Toshito, W. E. Keig, Y. Nagashima, H. Fujiyasu, J. A. Goodman, J. T. Hong, Y. Takeuchi, F. Tsushima, C. W. Walter, Soo-Bong Kim, S. Kasuga, Y. Fukuda, E. Kearns, Y. Totsuka, M. Koshiba, Hyosun Kim, C. McGrew, Yoshihiro Suzuki, K. Kobayashi, M. Nemoto, D. Kerr, T. Maruyama, Takashi Yamaguchi, M. D. Messier, S. Echigo, T. Kato, C. Mitsuda, P. G. Halverson, R. J. Wilkes, U. Golebiewska, K. K. Young, S. Mine, Y. Obayashi, Y. Gando, E. Blaufuss, Junichi Kanzaki, C. Mauger, J. Yoo, Masato Shiozawa, T. Barszczak, T. Oyabu, A. Suzuki, Tsuyoshi Nakaya, Masayuki Nakahata, Hirokazu Ishino, L. Wai, M. Oketa, J. W. Flanagan, Hiroshi Ogawa, M. R. Vagins, H. Kobayashi, W. Gajewski, Kate Scholberg, W. R. Kropp, Y. Oyama, Y. Hayato, T. Iwamoto, and Yusuke Koshio

Subjects
Physics, Nuclear and High Energy Physics, Particle physics, Physics::Instrumentation and Detectors, Cherenkov detector, Solar neutrino, High Energy Physics::Phenomenology, T2K experiment, law.invention, Neutrino detector, law, High Energy Physics::Experiment, Neutrino astronomy, Neutrino, Super-Kamiokande, Neutrino oscillation, Instrumentation
Abstract

Super-Kamiokande is the world's largest water Cherenkov detector, with net mass 50,000 tons. During the period April, 1996 to July, 2001, Super-Kamiokande I collected 1678 live-days of data, observing neutrinos from the Sun, Earth's atmosphere, and the K2K long-baseline neutrino beam with high efficiency. These data provided crucial information for our current understanding of neutrino oscillations, as well as setting stringent limits on nucleon decay. In this paper, we describe the detector in detail, including its site, configuration, data acquisition equipment, online and offline software, and calibration systems which were used during Super-Kamiokande I.

Published
2003
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2. 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
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3. 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
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4. Measurement of a small atmospheric ν/ν ratio

Author

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

Subjects
Momentum, Physics, Nuclear and High Energy Physics, Particle physics, High Energy Physics::Phenomenology, Monte Carlo method, Detector, Theoretical models, High Energy Physics::Experiment, Production (computer science), Atmospheric neutrino, Nuclear Experiment, Visible energy
Abstract

From an exposure of 25.5~kiloton-years of the Super-Kamiokande detector, 900 muon-like and 983 electron-like single-ring atmospheric neutrino interactions were detected with momentum $p_e > 100$ MeV/$c$, $p_\mu > 200$ MeV/$c$, and with visible energy less than 1.33 GeV. Using a detailed Monte Carlo simulation, the ratio $(\mu/e)_{DATA}/(\mu/e)_{MC}$ was measured to be $0.61 \pm 0.03(stat.) \pm 0.05(sys.)$, consistent with previous results from the Kamiokande, IMB and Soudan-2 experiments, and smaller than expected from theoretical models of atmospheric neutrino production.

Published
1998
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5. Erratum: Measurements of the Solar Neutrino Flux from Super-Kamiokande's First 300 Days [Phys. Rev. Lett. 81, 1158 (1998)]

Author

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

Subjects
Physics, Nuclear physics, Solar neutrino, General Physics and Astronomy, Flux, Super-Kamiokande
Published
1998
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6. Survival rates of patients with metastatic spinal cancer after scintigraphic detection of abnormal radioactive accumulation.

Author

Tatsui H, Onomura T, Morishita S, Oketa M, and Inoue T

Subjects
Adolescent, Adult, Aged, Aged, 80 and over, Bone and Bones diagnostic imaging, Female, Humans, Male, Middle Aged, Paralysis radiotherapy, Paralysis surgery, Radioactivity, Radionuclide Imaging, Retrospective Studies, Spinal Neoplasms diagnostic imaging, Time Factors, Neoplasm Metastasis diagnostic imaging, Spinal Neoplasms mortality, Spinal Neoplasms secondary, Spine diagnostic imaging, Survival Rate
Abstract

Study Design: This retrospective study analyzes the timing of spinal metastases and the survivability of patients with cancer after the detection of spinal metastases., Objective: To evaluate the timing of spinal metastases in primary lesions and the survivability of patients with metastatic spinal tumors., Summary of Background Data: Few studies have analyzed the influence of primary lesions on survival rates of patients with metastatic spinal tumors., Methods: This is a review of bone scintigraphy that was performed serially in patients with pulmonary cancer, breast cancer, prostatic cancer, cervical cancer, renal cancer, and gastric cancer from 1980 to 1991. To exclude false positive cases, the spinal areas showing abnormal accumulation on bone scintigrams were further examined by other methods of diagnostic imaging. The timing of scintigraphic detection of spinal metastases and the survivability were studied in 425 patients with spinal metastases. The survivability after spinal accumulation was determined by the Kaplan-Meier survival curve., Results: The mean period, from the diagnosis of the primary lesion to the detection of abnormal accumulation in the spine, was shortest in pulmonary cancer (3.6 +/- 6.1 months), and it was longest in breast cancer (29.4 +/- 33.5 months). The 1-year survival rate was high in breast cancer (78%) and prostatic cancer (83%), and it was low in pulmonary cancer (22%) and gastric cancer (0%), respectively. The 6-month survival rate of gastric cancer was 15%., Conclusions: When managing metastatic spinal tumors, it is essential to select therapeutic methods based on adequate consideration of the features of primary lesions and the expected prognosis.

Published
1996
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7. [A case of spinal glioblastoma with intracranial dissemination].

Author

Kawanishi M, Kuroiwa T, Nagasawa S, Ohta T, Oketa M, and Onomura T

Subjects
Brain Neoplasms diagnosis, Glioblastoma diagnosis, Humans, Magnetic Resonance Imaging, Male, Middle Aged, Spinal Cord Neoplasms diagnosis, Thoracic Vertebrae, Brain Neoplasms secondary, Glioblastoma secondary, Spinal Cord Neoplasms pathology
Abstract

A 50-year-old male developed gait disturbance and bilateral sensory disturbance in territories below Th 11 level in February, 1990. On February 26, 1990, an intradural tumor was partially removed at Th 11-12 levels, which was histologically diagnosed as glioblastoma multiforme; followed by post-operative radiotherapy (40Gy to the tumor area). CT scan of the brain was unremarkable and he was discharged home as ambulatory in July, 1990. Gait disturbance, occasional headache and vomiting developed in June, 1991. MRI revealed multiple spinal cord tumors at Th 11-12 and L 2-3 levels, as well as multiple intracranial tumors in the cerebellum, cingulate gyrus, and sylvian fissure, all of which were thought to be located in the cerebrospinal fluid (CSF) space. VP shunt was performed for hydrocephalus. MRI taken 2 months after operation demonstrated diffuse subarachnoid dissemination and new spinal cord tumors at C 3-4 and Th 3-10 levels. Although pathology of the intracranial tumors was not confirmed, dissemination from the spinal tumor was strongly suggested by the evidence including the long interval after the spinal cord operation, the location of the multiple tumors in the CSF space, and the simultaneous intraspinal dissemination. Only 31 cases with intracranial dissemination from malignant spinal astrocytoma or glioblastoma have been reported, and, of these, most were located around the brainstem, cerebellum, and other regions bordering the CSF space. In malignant spinal cord tumor, every effort should be made to prevent CSF dissemination at operation or to detect it as early as possible thereafter. MRI was found to be the most effective method for evaluating CSF dissemination.

Published
1993

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