Showing papers by "S. Nakayama published in 1999"
01 Jan 1999
TL;DR: A total of 614 upward through-going muons of minimum energy 1.6 GeV were observed by Super-Kamiokande during 537 detector live days as discussed by the authors.
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.)) × 10 −13 cm −2 s −1 sr −1 compared to an expected flux of (1.97 ± 0.44(theo.)) × 10 −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 �µ ↔ �� oscillation hypothesis with sin 2 2� > 0.4 and 1 × 10 −3 < �m 2 < 1 × 10 −1 eV 2 at 90 % confidence level.
285 citations
University of Tokyo1, Boston University2, Brookhaven National Laboratory3, University of California, Irvine4, California State University5, George Mason University6, Gifu University7, University of Hawaii at Manoa8, Kobe University9, Los Alamos National Laboratory10, Louisiana State University11, University of Maryland, College Park12, University of Chicago13, Stony Brook University14, Niigata University15, Osaka University16, Seoul National University17, Tohoku University18, Tokai University19, Tokyo Institute of Technology20, University of Warsaw21, University of Washington22, California Institute of Technology23, Stanford University24
TL;DR: In this article, a measurement of the energy spectrum of recoil electrons from solar neutrino scattering in the Super-Kamiokande detector is presented, where the shape of the measured spectrum is compared with the expectation for solar {sup 8}B neutrinos.
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 were obtained from 504 days of data taken between 31 May 1996 and 25 March 1998. The shape of the measured spectrum is compared with the expectation for solar {sup 8}B 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}{sup 2} of 25.3 with 15 degrees of freedom, corresponding to a 4.6{percent} confidence level. {copyright} {ital 1999} {ital The American Physical Society}
253 citations
University of Tokyo1, Boston University2, Brookhaven National Laboratory3, University of California, Irvine4, California State University, Dominguez Hills5, George Mason University6, Gifu University7, Kobe University8, Kyoto University9, Los Alamos National Laboratory10, Louisiana State University11, University of Maryland, College Park12, Stony Brook University13, Niigata University14, Osaka University15, Seoul National University16, Tohoku University17, Tokai University18, Tokyo Institute of Technology19, University of Warsaw20, University of Washington21, California Institute of Technology22
TL;DR: In this paper, the authors measured the upward through-going muon flux and calculated the stopping/through-going flux ratio R, which has less theoretical uncertainty than the expected values.
136 citations