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arXiv · 2008.08634

A Spectrometric Approach to Measuring the Rayleigh Scattering Length for Liquid Scintillator Detectors

Abstract

Good optical transparency is a fundamental requirement of liquid scintillator (LS) detectors. Characterizing the transparency of a liquid scintillator to its own emitted light is a key parameter to determine the overall sensitivity of a large-volume detector. The attenuation of light in an optical-pure LS is dominated by Rayleigh scattering, which poses an intrinsic limit to the transparency of LS. This work presents a spectrometric approach of measuring the wavelength-dependent scattering length of liquids by applying the Einstein-Smoluchowski theory to a measurement of scattered light intensity. The scattering lengths of linear alkyl benzene (LAB) and EJ309-base (Di-isopropylnaphthalene, DIN) were measured and are reported in the wavelength range of 410 to 520 nm. The spectral peak of scintillation light emitted by a nominal LS is around 430 nm at which the scattering length for LAB and EJ-309-base was determined to be 27.9 +/- 2.3 m and 6.1 +/- 0.6 m respectively.

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S. S. Gokhale, R. Rosero, R. Diaz Perez, C. Camilo Reyes, S. Hans, M. Yeh. 2020-08-19. A Spectrometric Approach to Measuring the Rayleigh Scattering Length for Liquid Scintillator Detectors. https://doi.org/10.1088/1748-0221/16/03/p03009

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