TY - JOUR
T1 - A scintillator purification system for a large scale solar neutrino experiment
AU - Benziger, Jay Burton
AU - Johnson, Michael
AU - Calaprice, Frank
AU - Chen, M.
AU - Darnton, N.
AU - Loeser, R.
AU - Vogelaar, R. B.
N1 - Funding Information:
We thank for NSF (PHY-9313919) for their support of this work. We also thank the INFN for funding support of the hot oil and nitrogen systems. One of us (FPC) thanks the INFN for support during a sabbatical leave to help oversee the operation of the purification system. We finally thank the following people for their aid in data analysis: G. Almonti (for the 85 Kr analyses), L. Cadonati (for the radon analyses), C. Galbiati, S. Magni, E. Meroni, G. Ranucci, S. Schoenert and M. Lowry.
PY - 1998/11/11
Y1 - 1998/11/11
N2 - An on-line purification system for a large-scale low-background liquid scintillation detector has been tested with the 5 t liquid scintillation detector, the Counting Test Facility at Gran Sasso. Counter-current water extraction removes polar and charged impurities such as ions and metal salts. Vacuum distillation of the entire scintillator has been applied to remove both radioactive impurities and chemical impurities that affect the optical properties of the scintillator. Filtration with a 0.05 μm particulate filter removed suspended dust particles that may contain U, Th and K. Nitrogen stripping was employed to remove dissolved water and noble gases (e.g. 85Kr) from the scintillator. The system has effectively reduced the internal back in the 5 t liquid scintillation detector from 470 ± 90 events/d to the detection limit of the detector (± 45 events/d) in the energy window 250 < E < 800 keV.
AB - An on-line purification system for a large-scale low-background liquid scintillation detector has been tested with the 5 t liquid scintillation detector, the Counting Test Facility at Gran Sasso. Counter-current water extraction removes polar and charged impurities such as ions and metal salts. Vacuum distillation of the entire scintillator has been applied to remove both radioactive impurities and chemical impurities that affect the optical properties of the scintillator. Filtration with a 0.05 μm particulate filter removed suspended dust particles that may contain U, Th and K. Nitrogen stripping was employed to remove dissolved water and noble gases (e.g. 85Kr) from the scintillator. The system has effectively reduced the internal back in the 5 t liquid scintillation detector from 470 ± 90 events/d to the detection limit of the detector (± 45 events/d) in the energy window 250 < E < 800 keV.
KW - Liquid scintillator
KW - Radiopurity
KW - Solar neutrino
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U2 - 10.1016/S0168-9002(98)00767-0
DO - 10.1016/S0168-9002(98)00767-0
M3 - Article
AN - SCOPUS:0032204579
SN - 0168-9002
VL - 417
SP - 278
EP - 296
JO - Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
JF - Nuclear Instruments and Methods in Physics Research, Section A: Accelerators, Spectrometers, Detectors and Associated Equipment
IS - 2-3
ER -