| Автор | Motoyasu Ikeda |
| Автор | the Super-Kamiokande Collaboration |
| Дата выпуска | 2008-11-01 |
| dc.description | The third phase of Super-Kamiokande experiment (SK-III) has been running since 12th July, 2006. The SK-III detector is achieved 40% photo-cathode coverage with 11,129 20-inch PMTs. One of the physics goals in SK-III is observing the transition of solar neutrino oscillations between vacuum and matter oscillation around 4MeV. From 24th January, 2007 to 2nd March, 2008, we obtained data of live-time 288.9 days with energy threshold 6.5MeV (Full Final sample: FF sample). For data with a lower energy threshold 5.0MeV, we needed remove high radon contaminated period from the FF sample, then we obtained another data sample (Radon reduced sample: RR sample) with live-time 191.7 days. The current measurements show that SK-III has already achieved a similar signal to noise ratio as SK-I for energy range from 5.0 to 20.0MeV, and the solar angle distribution of FF sample shows that the solar neutrino event rate also looks consistent with SK-I for energy range from 6.5 to 20.0MeV. As for the RR sample, although the vertex distribution of low energy events is not uniform in the detector and there are more BG events in the edge of fiducial volume, it is clear that SK-III BG level is smaller than that of SK-I in the central region of the detector. Finally, the future plan for lowering the energy threshold shows a 2a discovery potential of the energy spectrum upturn with 3 years of observation after both software and hardware improvements. |
| Формат | application.pdf |
| Издатель | Institute of Physics Publishing |
| Копирайт | © 2008 IOP Publishing Ltd |
| Название | Solar neutrino measurements with Super-Kamiokande III |
| Тип | paper |
| DOI | 10.1088/1742-6596/136/4/042009 |
| Electronic ISSN | 1742-6596 |
| Print ISSN | 1742-6588 |
| Журнал | Journal of Physics: Conference Series |
| Том | 136 |
| Первая страница | 42009 |
| Последняя страница | 42009 |
| Аффилиация | Motoyasu Ikeda; Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Gifu, 506-1205 Japan |
| Аффилиация | the Super-Kamiokande Collaboration; Kamioka Observatory, Institute for Cosmic Ray Research, University of Tokyo, Kamioka, Gifu, 506-1205 Japan |
| Выпуск | 4 |
