8 research outputs found
Borexino calibrations: Hardware, Methods, and Results
Borexino was the first experiment to detect solar neutrinos in real-time in
the sub-MeV region. In order to achieve high precision in the determination of
neutrino rates, the detector design includes an internal and an external
calibration system. This paper describes both calibration systems and the
calibration campaigns that were carried out in the period between 2008 and
2011. We discuss some of the results and show that the calibration procedures
preserved the radiopurity of the scintillator. The calibrations provided a
detailed understanding of the detector response and led to a significant
reduction of the systematic uncertainties in the Borexino measurements
Large underground, liquid based detectors for astro-particle physics in Europe: scientific case and prospects
This document reports on a series of experimental and theoretical studies
conducted to assess the astro-particle physics potential of three future
large-scale particle detectors proposed in Europe as next generation
underground observatories. The proposed apparatus employ three different and,
to some extent, complementary detection techniques: GLACIER (liquid Argon TPC),
LENA (liquid scintillator) and MEMPHYS (\WC), based on the use of large mass of
liquids as active detection media. The results of these studies are presented
along with a critical discussion of the performance attainable by the three
proposed approaches coupled to existing or planned underground laboratories, in
relation to open and outstanding physics issues such as the search for matter
instability, the detection of astrophysical- and geo-neutrinos and to the
possible use of these detectors in future high-intensity neutrino beams.Comment: 50 pages, 26 figure
Phenylxylylethane (PXE): A high-density, high-flash point organic liquid scintillator for low energy neutrino experiments
We report on the study of a new liquid scintillator target for neutrino interactions in the framework of the research and development program of the Borexino solar neutrino experiment. The scintillator consists of 1,2-dimethyl-4-(1-phenylethyl)-benzene (phenyl-o- xylylethane, PXE) as solvent and 1,4-diphenylbenzene (para-Terphenyl, p-Tp) as primary and 1,4-bis(2- methylstyryl)benzene (bis-MSB) as secondary solute. The density close to that of water and the high flash point makes it an attractive option for large scintillation detectors in general. The study focused on optical properties, radioactive trace impurities and novel purification techniques of the scintillator. Attenuation lengths of the scintillator mixture of 12 m at 430 nm were achieved after purification with an alumina column. A radiocarbon isotopic ratio of has been measured in the scintillator. Initial trace impurities, e.g.could be purified to levels below by silica gel solid column purification