Abstract
Abstract
DANSS is a spectrometer for reactor antineutrinos based on
plastic scintillator. The sensitive volume of the detector is made
of 2500 polystyrene based scintillator plates with wavelength
shifting (WLS) fiber readout (strips). We present a study of the
light yield of strips during 6.5 years of DANSS continuous
running. Overall ageing at the rate
0.55 ± 0.05 (syst.) % per year is observed that is
considerably smaller than in other similar experiments. We also
observe the WLS fiber attenuation length shortening at the rate
0.26 ± 0.04(stat.) % per year.