| Records |
| Author |
Super-Kamiokande Collaboration (Abe, K. et al); Molina Sedgwick, S. |
| Title |
Neutron tagging following atmospheric neutrino events in a water Cherenkov detector |
Type |
Journal Article |
| Year |
2022 |
Publication |
Journal of Instrumentation |
Abbreviated Journal |
J. Instrum. |
| Volume |
17 |
Issue |
10 |
Pages |
P10029 - 41pp |
| Keywords |
Particle identification methods; Cherenkov detectors; Neutrino detectors; Large detector systems for particle and astroparticle physics |
| Abstract |
We present the development of neutron-tagging techniques in Super-Kamiokande IV using a neural network analysis. The detection efficiency of neutron capture on hydrogen is estimated to be 26%, with a mis-tag rate of 0.016 per neutrino event. The uncertainty of the tagging efficiency is estimated to be 9.0%. Measurement of the tagging efficiency with data from an Americium-Beryllium calibration agrees with this value within 10%. The tagging procedure was performed on 3,244.4 days of SK-IV atmospheric neutrino data, identifying 18,091 neutrons in 26,473 neutrino events. The fitted neutron capture lifetime was measured as 218 +/- 9 μs. |
| Address |
[Abe, K.; Haga, Y.; Hayato, Y.; Hiraide, K.; Ieki, K.; Ikeda, M.; Imaizumi, S.; Iyogi, K.; Kameda, J.; Kanemura, Y.; Kataoka, Y.; Kato, Y.; Kishimoto, Y.; Miki, S.; Mine, S.; Miura, M.; Mochizuki, T.; Moriyama, S.; Nagao, Y.; Nakahata, M.; Nakajima, T.; Nakano, Y.; Nakayama, S.; Okada, T.; Okamoto, K.; Orii, A.; Sato, K.; Sekiya, H.; Shiozawa, M.; Sonoda, Y.; Suzuki, Y.; Takeda, A.; Takemoto, Y.; Takenaka, A.; Tanaka, H.; Tasaka, S.; Tomura, T.; Ueno, K.; Watanabe, S.; Yano, T.; Yokozawa, T.] Univ Tokyo, Inst Cosm Ray Res, Kamioka Observ, Gifu, Akita 5061205, Japan, Email: hayato@icrr.u-tokyo.ac.jp |
| Corporate Author |
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Thesis |
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| Publisher |
IOP Publishing Ltd |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
|
| ISSN |
1748-0221 |
ISBN |
|
Medium |
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| Area |
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Expedition  |
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Conference |
|
| Notes |
WOS:000898723700008 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
5441 |
| Permanent link to this record |
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| Author |
Super-Kamiokande Collaboration (Abe, K. et al); Molina Sedgwick, S. |
| Title |
Solar neutrino measurements using the full data period of Super-Kamiokande-IV |
Type |
Journal Article |
| Year |
2024 |
Publication |
Physical Review D |
Abbreviated Journal |
Phys. Rev. D |
| Volume |
109 |
Issue |
9 |
Pages |
092001 - 44pp |
| Keywords |
|
| Abstract |
An analysis of solar neutrino data from the fourth phase of Super-Kamiokande (SK-IV) from October 2008 to May 2018 is performed and the results are presented. The observation time of the dataset of SK- IV corresponds to 2970 days and the total live time for all four phases is 5805 days. For more precise solar neutrino measurements, several improvements are applied in this analysis: lowering the data acquisition threshold in May 2015, further reduction of the spallation background using neutron clustering events, precise energy reconstruction considering the time variation of the PMT gain. The observed number of solar neutrino events in 3.49-19.49 MeV electron kinetic energy region during SK-IV is 65, 443(-388)(+390) (stat.) +/- 925(syst.) events. Corresponding B-8 solar neutrino flux is (2.314 +/- 0.014(stat.) +/- 0.040(syst.)) x 106 cm(-2) s(-1), assuming a pure electron-neutrino flavor component without neutrino oscillations. The flux combined with all SK phases up to SK-IV is (2.336 +/- 0.011(stat.) +/- 0.043(syst.)) x 106 cm(-2) s(-1). Based on the neutrino oscillation analysis from all solar experiments, including the SK 5805 days dataset, the best-fit neutrino oscillation parameters are sin(2)theta(12,solar) = 0.306 +/- 0.013 and Delta m(21,solar)(2) = (6.10(-0.81)(+0.95)) x 10(-5) eV(2), with a deviation of about 1.5 sigma from the Delta m(21)(2) parameter obtained by KamLAND. The best-fit neutrino oscillation parameters obtained from all solar experiments and KamLAND are sin(2)theta(12, global) = 0.307 +/- 0.012 and Delta m(21,) (2)(global) = (7.50(-0.18)(+0.19)) x 10(-5) eV(2). |
| Address |
[Abe, K.; Bronner, C.; Hayato, Y.; Hiraide, K.; Hosokawa, K.; Ieki, K.; Ikeda, M.; Imaizumi, S.; Iyogi, K.; Kameda, J.; Kanemura, Y.; Kaneshima, R.; Kashiwagi, Y.; Kataoka, Y.; Kato, Y.; Kishimoto, Y.; Miki, S.; Mine, S.; Miura, M.; Mochizuki, T.; Moriyama, S.; Nagao, Y.; Nakahata, M.; Nakano, Y.; Nakayama, S.; Noguchi, Y.; Okada, T.; Okamoto, K.; Orii, A.; Sato, K.; Sekiya, H.; Shiba, H.; Shimizu, K.; Shiozawa, M.; Sonoda, Y.; Suzuki, Y.; Takeda, A.; Takemoto, Y.; Takenaka, A.; Tanaka, H.; Watanabe, S.; Yano, T.] Univ Tokyo, Kamioka Observ, Inst Cosm Ray Res, Kamioka, Gifu 5061205, Japan |
| Corporate Author |
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Thesis |
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| Publisher |
Amer Physical Soc |
Place of Publication |
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Editor |
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| Language |
English |
Summary Language |
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Original Title |
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| Series Editor |
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Series Title |
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Abbreviated Series Title |
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| Series Volume |
|
Series Issue |
|
Edition |
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| ISSN |
2470-0010 |
ISBN |
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Medium |
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| Area |
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Expedition |
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Conference |
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| Notes |
WOS:001261161700001 |
Approved |
no |
| Is ISI |
yes |
International Collaboration |
yes |
| Call Number |
IFIC @ pastor @ |
Serial |
6210 |
| Permanent link to this record |
