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Borexino is a particle physics experiment to study low energy (sub-MeV) solar neutrinos. The name Borexino is the Italian diminutive of BOREX (Boron solar neutrino experiment). The experiment is located at the Laboratori Nazionali del Gran Sasso near the town of L'Aquila, Italy, and is supported by an international collaboration with researchers from Italy, the United States, Germany, France, Poland and Russia. The experiment is funded by multiple national agencies including the INFN (National Institute for Nuclear Physics) and the NSF (National Science Foundation). The detector is a high-purity liquid scintillator calorimeter. It is placed within a stainless steel sphere and shielded by a water tank. The primary aim of the experiment is to make a precise measurement of the beryllium-7 neutrino flux from the sun and comparing it to the Standard solar model prediction. This will allow scientists to further understand the nuclear fusion processes taking place at the core of the Sun and will also help determine properties of neutrino oscillations, including the MSW effect. Other goals of the experiment are to detect boron-8, pp, pep and CNO solar neutrinos as well as antineutrinos from the Earth and nuclear power plants. The project may also be able to detect neutrinos from supernova within our galaxy. Borexino is a member of the Supernova Early Warning System. == Results == As of May 2007, the Borexino detector started taking data.〔(【引用サイトリンク】publisher=Laboratori Nazionali del Gran Sasso press release )〕 The project first detected solar neutrinos in August 2007. This detection occurred in real-time. The data analysis was further extended in 2008. In 2010, geoneutrinos from Earth's interior have been observed for the first time. These are anti-neutrinos produced in radioactive decays of uranium, thorium, potassium, and rubidium.〔(【引用サイトリンク】publisher=INFN press release )〕 In 2011, the experiment published a precision measurement of the beryllium-7 neutrino flux,〔(【引用サイトリンク】publisher=Borexino Collaboration press release )〕 as well as the first evidence for the pep solar neutrinos.〔(【引用サイトリンク】publisher=PhysOrg.com )〕 In 2012, they published the results of measurements of the speed of CERN Neutrinos to Gran Sasso. The results were consistent with the speed of light. See measurements of neutrino speed. In 2013, they set a limit on sterile neutrino parameters. They also extracted a signal of geoneutrinos, which gives insight into radioactive element activity in the earth's crust.〔(【引用サイトリンク】url=http://cerncourier.com/cws/article/cern/53073 )〕 In 2014, they published an analysis of the proton–proton fusion activity in the solar core, finding output has been solar activity has been consistent.〔(【引用サイトリンク】url=http://cerncourier.com/cws/article/cern/58520 )〕 In 2015, an updated spectral analysis of geoneutrinos was presented. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Borexino」の詳細全文を読む スポンサード リンク
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