Proton Calorimetry/Meetings/2017/03/29: Difference between revisions

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'''ABF''':
'''ABF''':
*  
* Looking at specific peak PMT current:
** Acquire data with different rates:
** Calculate average current to compare at what point saturation occurs.
** Matches predictions almost exactly!
** Small rise at "saturation" current before drop off.
* Will pass on information to Hamamatsu to "guide" them in producing lower gain PMTs.


'''LK''':
'''LK''':
* [http://www.hep.ucl.ac.uk/pbt/wikiData/presentations/2017/LK20170329_ProtonBuildUp.pdf Looking at dose build-up effect in proton therapy and secondary particles].
* [http://www.hep.ucl.ac.uk/pbt/wikiData/presentations/2017/LK20170329_ProtonBuildUp.pdf Looking at dose build-up effect in proton therapy and secondary particles].
** Dose increases at start of X-ray depth dose curve due to short-range electron shower.
** Secondary particles in Geant4 difficult to characterise due to range cut.
** Effect present for protons but much smaller.
** <code>GetTotalEnergyDeposit()</code> doesn't include energy from secondary particles...
* Managed to reproduce results over 10mm from Benjamin Tham's previous simulations.
** Need to check whether 20 micron range cut is short enough with '''Adam Gibson'''.
* Build-up effect present for both electrons and secondary hadrons, but build-up much shorter for electron shower (~1mm).
* Clear build-up effect from secondary protons:
* Will run simulations for 100MeV and 200MeV with higher statistics.
** Need to check RBE of the resulting short-range protons.
** Effect of hadronic build-up means Bragg curve incorrect for entrance dose.

Latest revision as of 14:11, 29 March 2017

Minutes for UCL Proton Calorimetry Meeting, 29th March 2017 (D17, Physics & Astronomy, UCL)

Present

Simon Jolly, Laurent Kelleter, Anastasia Basharina-Freshville

ABF:

  • Looking at specific peak PMT current:
    • Acquire data with different rates:
    • Calculate average current to compare at what point saturation occurs.
    • Matches predictions almost exactly!
    • Small rise at "saturation" current before drop off.
  • Will pass on information to Hamamatsu to "guide" them in producing lower gain PMTs.

LK:

  • Looking at dose build-up effect in proton therapy and secondary particles.
    • Secondary particles in Geant4 difficult to characterise due to range cut.
    • GetTotalEnergyDeposit() doesn't include energy from secondary particles...
    • Need to check whether 20 micron range cut is short enough with Adam Gibson.
  • Clear build-up effect from secondary protons:
    • Need to check RBE of the resulting short-range protons.
    • Effect of hadronic build-up means Bragg curve incorrect for entrance dose.