European underground laboratories: An overview

Underground laboratories are complementary to those where the research in fundamental physics is made using accelerators. This report focus on the logistic and on the background features of the most relevant laboratories in Europe, stressing also on the low background facilities available. In particular the report is focus on the laboratories involved in the new Europeean project ILIAS with the aim to support the European large infrastructures operating in the astroparticle physics area.Comment: 9 pages, 6 figures, Invited talk: Topical Workshop in Low Radioactivity Techniques (Sudbury, Canada) December 12-14, 2004. To be publish in AIP conference proceeding

Neutrinos and (Anti)neutrinos from Supernovae and from the Earth in the Borexino detector

The main goal of the Borexino detector, in its final phase of construction in the Gran Sasso underground laboratory, is the direct observation and measurement of the low energy component of neutrinos coming from the Sun. The unique low energy sensitivity and ultra-low background bring new capabilities to attack problems in neutrino physiscs other than solar ones. Investigation about the study of Supernoavae neutrinos and neutrino coming from the Earth (Geoneutrinos) are here resumed.Comment: 7 pages, 6 figures, proceedings of the The 1st Yamada Symposium on Neutrinos and Dark Matter in Nuclear Physics June 9-14, 2003, Nara Japa

Borexino: A real time liquid scintillator detector for low energy solar neutrino study

Borexino is a large unsegmented calorimeter featuring 300 tons of liquid scintillator, contained in a 8.5 meter nylon vessel, viewed by 2200 PMTs. The main goal of Borexino is the study, in real time, of low energy solar neutrinos, and in particular, the monoenergetic neutrinos coming from $^7Be$, which is one of the missing links on the solar neutrino problem. The achievement of high radiopurity level, in the order of $10^{-16} g/g$ of U/Th equivalent, necessary to the detection of the low energy component of the solar neutrino flux, was proved in the Borexino prototype: the Counting Test Facility. The detector is located underground in the Laboratori Nazionali del Gran Sasso in the center of Italy at 3500 meter water equivalent depth. In this paper the science and technology of Borexino are reviewed and its main capabilities are presented.Comment: 8 pages, 3 figures, 10th International Conference on Calorimetry in High Energy Physics. http://3w.hep.caltech.edu/calor02

Solar Neutrino Physics: historical evolution, present status and perspectives

Solar neutrino physics is an exciting and difficult field of research for physicists, where astrophysics, elementary particle and nuclear physics meet. \ The Sun produces the energy that life has been using on Earth for many years, about $10^9$ y, emits a lot of particles: protons, electrons, ions, electromagnetic quanta... among them neutrinos play an important role allowing to us to check our knowledge on solar characteristics. The main aim of this paper is to offer a practical overview of various aspects concerning the solar neutrino physics: after a short historical excursus, the different detection techniques and present experimental results and problems are analysed. Moreover, the status of art of solar modeling, possible solutions to the so called solar neutrino problem (SNP) and planned detectors are reviewed.Comment: 139 pages, 42 figure

Borexino

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Advancements in solar neutrino physics

We review the results of solar neutrino physics, with particular attention to the data obtained and the analyses performed in the last decades, which were determinant to solve the solar neutrino problem (SNP), proving that neutrinos are massive and oscillating particles and contributing to refine the solar models. We also discuss the perspectives of the presently running experiments in this sector and of the ones planned for the near future and the impact they can have on elementary particle physics and astrophysics.Comment: 15 page

Solar neutrino detection

More than 40 years ago, neutrinos where conceived as a way to test the validity of the solar models which tell us that stars are powered by nuclear fusion reactions. The first measurement of the neutrino flux, in 1968 in the Homestake mine in South Dakota, detected only one third of the expected value, originating what has been known as the Solar Neutrino Problem. Different experiments were built in order to understand the origin of this discrepancy. Now we know that neutrinos undergo oscillation phenomenon changing their nature traveling from the core of the Sun to our detectors. In the work the 40 year long saga of the neutrino detection is presented; from the first proposals to test the solar models to last real time measurements of the low energy part of the neutrino spectrum.Comment: 8 pages, 5 figures. III School on Cosmic Rays and Astrophysics August 25 to September 5, 2008 Arequipa (Peru) AIP conference proceedin

Fabrication of quencher-free liquid scintillator-based, high-activity 222^{222}Rn calibration sources for the Borexino detector

A reliable and consistently reproducible technique to fabricate $^{222}$Rn-loaded radioactive sources ($\sim$0.5-1 kBq just after fabrication) based on liquid scintillator (LS), with negligible amounts of LS quencher contaminants, was implemented. This work demonstrates the process that will be used during the Borexino detector's upcoming calibration campaign, with one or several $\sim$100 Bq such sources will be deployed at different positions in its fiducial volume, currently showing unprecedented levels of radiopurity. These sources need to fulfill stringent requirements of $^{222}$Rn activity, transparency to the radiations of interest and complete removability from the detector to ensure their impact on Borexino's radiopurity is negligible. Moreover, the need for a clean, undistorted spectral signal for the calibrations imposes a tight requirement to minimize quenching agents ("quenchers") to null or extremely low levels