Nanoparticle based scintillators and wavelenght shifters for Particle Physics Detectors.
Cattadori C.M., Brovelli S., Meinardi F.
I - Fisica nucleare e subnucleare
Aula Palazzo dell'Emiciclo - Sala Ipogea - Martedì 24 h 09:00 - 12:00
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The transmission of light by Total Internal Reflection (TIR) is exploited in plastic scintillator light guides, optical fibers, liquid scintillator cells, etc. Fibers and plastic scintillators may be doped with organic dye molecules to match the spectral quantum efficiency of the adopted photodetector. In the last 5 years the tremendous development of nano-technologies and the ability to produce luminescent nano-particles at well tunable absorption and emission wavelengths, allowed a significant increase of the Light Solar Concentrators power conversion efficiencies. In particle physics detectors large volumes of cryogenic noble gases (Ar, Xe) or organic liquid scintillator are the targets, and the UV-VUV light emitted by the ionizing radiation must be downshifted when it first interacts, to reach and match the photodetector sensitivity. This is accomplished by coating with organic fluorescent molecules the photodetectors and/or the reflectors surfaces. In this work we explore the use of a nanoparticle-based wavelength shifter embedded in a plastic scintillator as PEN or in PMMA matrix, for particle physics applications, and present the first comparative results for the downshift of UV-VUV light by nano-particle compounds, with respect to the so far adopted tetraphenylbutadiene (or equivalent) wavelength shifter coatings.