  For the simulation of the scintillation and Cherenkov light propagation in
large liquid scintillator detectors a detailed knowledge about the absorption
and emission spectra of the scintillator molecules is mandatory. Furthermore
reemission probabilities and quantum yields of the scintillator components
influence the light propagation inside the liquid. Absorption and emission
properties are presented for liquid scintillators using 2,5-Diphenyloxazole
(PPO) and 4-bis-(2-Methylstyryl)benzene (bis-MSB) as primary and secondary
wavelength shifter. New measurements of the quantum yields for various aromatic
molecules are shown.

Instrumentation and Detectors