LhARA radiobiology; meeting: 16Oct25; 14:00 BST

ZOOM: ​https://imperial-ac-uk.zoom.us/j/98220889714?pwd=SM90vOF7BKSXoU3mD9q7OwBQo4IVB3.1

Attended: CW, RW, AFr, EM, BT, TP, JMcG, ND, JP, KL

Meeting Notes

1. Minutes and actions:

• CD/RW/ND: Meet to discuss RCF calibration
  • Done
• RW: Fine-tune installation of cell carousel
• DA: Sample simulated beamline more frequently
  • Done
• CD: Investigate defocussing to improve uniformity
  • Done
• CD/RW: Design RCF holder
  • Done
• KL: Discuss sparse diagnostic at CLF
  • Done

2. Strathclyde: BT, ED, RW
   

• Processing the RCF from Phase 1
  • Proton Number Results:
    • Collected the source spectrums at 40mm from the laser target
    • Producing similar numbers of protons as Nick
    • See an interesting amount of lower energy dose
      • Not too concerned as expect these to get absorbed in the mylar
    • See transmission of ~1% for 8-10MeV and 4% for 10MeV
    • Slides
    • Robbie to send the spectra to Tony who can pass it through his G4 simulation of the cell dish and return dose rate

3. Simulation CD, DA, AFr:
   

• Results of an Au foil in the beamline with a better source (Afr):
  • Greatly reduced the CV (Coefficient of Variation) in all cases due to better source
  • Foil in tube too close to the cells to make a difference
  • At tube entrance providing possibly the best option at 10.9%
  • Slides
  • Robbie provided locations of Gold foil:
    • [raw_attachment:AU_Foil_placement_15102025_v1.pdf Slides]
• Results of defocussing the beam
  • Manage a nice uniformity when only using a 10MeV gaussian
  • However, when a laser-driven source is inputted a cross reappears
  • Repeat uniformity tests but using selection of laser-driven spectrum
  • Slides
• Results of 8MeV setup:
  • Rough results but appears the quads need to be moved closer to the source and closer together
  • Repeat with selection of laser-driven spectrum
• Next minimise CV for best quad and gold foil locations
  • 2x2cm foil

4. BioPrep EM, JP:
   

• Hoods up and running
  • Emma sent the risk assessments and cost forms to Mark
  • Online training to be completed
• Check the incubator at SCAPA
  • Switch on the gas on in the incubator should be 5%
  • Water from the bottom needs to be distilled
• Final confirmation of dates
  • Week 1: 27/10 - 31/10
  • Week 2: 3/11 - 7/11
  • Week 3: 17/11 - 21/11
  • Next Thursday: LAST possible date for the discussion of the irradiation plan
• Contact Marie Boyd? - Yes
• Cells need to be fixed and stained - 9 days after irradiating
  • Diaza is best placed for this
  • Contact Marie Boyd as well

• Discussion Point: Recreate the setup at Birmingham?
  • Too much effort for what it would tell us
  • Cyclotron struggles to have a stable beam with less than 12MeV protons

5. Beam Diagnostics KL, CD:
   

• Show RCF holder idea
  • Has reference to the outer curve of the carousel
  • Introduce a lip to fix this
  • Cut the RCF to 0.5mm of the measurements of the holder
  • Design sent to CLF to be cut
  • Slide
• Add Lanex to the outside of the cell dish to check the beam is present
  • Outer diameter of cell dish is 2.2cm

6. DoNM

• Next Week: 23th Oct

7. AoB

• Excel sheet complete with shot plan: ​https://docs.google.com/spreadsheets/d/13vkixxNBZX42WFtxw7_MFJTU-gc06J19N8zpTcMKFys/edit?usp=sharing
• If visiting SCAPA please email Robbie and fill it out on the Google excel sheet

Summary of actions

• RW: Send proton numbers to Tony to get the dose rate
• CD/DA/Afr: Find final beam setup with gold foil
• CD: Find alternative 8MeV setup
• EM/JMcG/DA/more visitors: Complete the online training indicated by Mark
• CW/RW: Turn on and clean the water in the incubators
• CW/Most likely to get their attention: Contact Marie Boyd
• RW: Add lip to RCF holder

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