  We has set up a light scattering spectrometer to study the depolarization of
light scattering in linear alkylbenzene. From the scattering spectra it can be
unambiguously shown that the depolarized part of light scattering belongs to
Rayleigh scattering. The additional depolarized Rayleigh scattering can make
the effective transparency of linear alkylbenzene much better than it was
expected. Therefore sufficient scintillation photons can transmit through the
large liquid scintillator detector of JUNO. Our study is crucial to achieving
the unprecedented energy resolution 3\%/$\sqrt{E\mathrm{(MeV)}}$ for JUNO
experiment to determine the neutrino mass hierarchy. The spectroscopic method
can also be used to judge the attribution of the depolarization of other
organic solvents used in neutrino experiments.
