4-8 July 2016
Kramer Law building
Africa/Johannesburg timezone
Paper Review: Initial screening in progress
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A study into the rate of photo-bleaching undergone by radiation damaged plastic scintillators

Presented by Ms. Harshna JIVAN on 6 Jul 2016 from 14:20 to 14:40
Type: Oral Presentation
Track: Track A - Division for Physics of Condensed Matter and Materials


Plastic scintillators play an important role in the field of detector physics due to their ability to undergo luminescence when interacting with ionising radiation. They typically consist of a polymer base containing an aromatic ring structure as well as small concentrations of fluorescent dopants. The π-electrons from the aromatic structure give rise to the primary scintillation mechanism, whilst the added fluors boost the eventual light yield as well as shift the wavelength of the emitted light. Upon excitation by energetic UV light (< 250 nm) in air, the scintillation mechanism can be stimulated with the fluorescent medium being subjected to the effect of photo-bleaching. Photo-bleaching leads to the chemical alteration of fluors, and renders them unable to fluoresce, thereby reducing the light yield of the scintillators. In this study, we investigate the rate of photo-bleaching for several plastic scintillators using an excitation laser of 229 nm. We further investigate the effect on the photo-bleaching rate for samples which have been subjected to proton induced radiation damage. The study will contribute to a comparative to be used by the Tile Calorimeter of the ATLAS detector where scintillators employed in the GAP region will be replaced in 2018.






Bruce Mellado Bruce.Mellado@wits.ac.za University of the Witwatersrand






Location: Kramer Law building
Address: UCT Middle Campus Cape Town
Room: LT1

Primary authors