4-8 July 2016
Kramer Law building
Africa/Johannesburg timezone
<a href="http://events.saip.org.za/internalPage.py?pageId=10&confId=86">The Proceedings of SAIP2016</a> published on 24 December 2017

Understanding proton induced radiation damage in plastic scintillators using electron paramagnetic resonance and DFT modelling

5 Jul 2016, 14:20
20m
4B (Kramer Law building)

4B

Kramer Law building

UCT Middle Campus Cape Town
Oral Presentation Track A - Division for Physics of Condensed Matter and Materials Division for Physics of Condensed Matter and Materials (2)

Speaker

Mr Chad Pelwan (University of Witwatersrand)

Level for award<br>&nbsp;(Hons, MSc, <br> &nbsp; PhD, N/A)?

MSc

Apply to be<br> considered for a student <br> &nbsp; award (Yes / No)?

Yes

Abstract content <br> &nbsp; (Max 300 words)<br><a href="http://events.saip.org.za/getFile.py/access?resId=0&materialId=0&confId=34" target="_blank">Formatting &<br>Special chars</a>

Plastic scintillators form and integral part of particle detectors, such as the ATLAS detector at the LHC, as they are able to measure energies and track momenta of particles after a collision. Electron paramagnetic resonance (EPR) has been employed to study unpaired electrons and ions that are present in pristine and damaged plastic scintillator samples. Six different types of plastics were investigated, based on either polystyrene or polyvinyl toluene (PVT) . Samples were subjected to irradiation doses between 0.8 – 80.0 MGy using 6 MeV protons. EPR studies conducted on these samples showed a decrease in g-factor of each sample with an increase dose. It is suggested that an increase in dose introduces secondary electrons and ions into the system increasing the spin density and the relaxation time. Computational DFT modeling of polystyrene and PVT monomers and dimers show that damaging the molecules decreases components of the g-tensor and alters the components of the hyperfine tensor related to the g-factor and relaxation time, respectfully.

Would you like to <br> submit a short paper <br> for the Conference <br> Proceedings (Yes / No)?

Yes

Main supervisor (name and email)<br>and his / her institution

Prof. Bruce Mellado, Bruce.Mellado@Wits.ac.za, The University of the Witwatersrand

Please indicate whether<br>this abstract may be<br>published online<br>(Yes / No)

Yes

Primary author

Mr Chad Pelwan (University of Witwatersrand)

Co-authors

Prof. Bruce Mellado (University of Wisconsin - Madison) Mr Charles Sandrock (University of the Witwatersrand) Prof. Daniel Joubert (School of Physics, University of the Witwatersrand) Prof. ELIAS SIDERAS-HADDAD (University of the Witwatersrand) Mr Gerrard Peters (University of the Witwatersrand) Mr Guy Moise DONGHO NGUIMDO (University of the Witwatersrand, Johannesburg) Ms Harshna Jivan (University of the Witwatersrand) Prof. Jonathan Keartland (University of the Witwatersrand) Ms Joyful Mdhluli (University of the Witwatersrand) Mr Kamela Sekonya (iThemba LABS (Gauteng)) Morgan Madhuku (iThemba LABS)

Presentation Materials

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