LhARA radiobiology; meeting: 22Jan26; 14:00 BST

Attended: DA, JMcG, PH, MH, EM, RW, AFr, KL, CD

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

Meeting Notes

1. Minutes and actions completed:

• CD: Tell Emma the min and max dose seen on the cell dish
  • DONE
• RW, ED: Tell Peter the dimensions of the vacuum chamber
  • DONE

2. In-Person Meeting

• Date: DECIDED 24th Feb at Birmingham
• lettuceMeet: ​https://lettucemeet.com/l/lWwgW

3. SCAPA RW,ED:

• General Update
  • Laser down again
  • Not booked in for beamtime until April
• Beamline Developments:
  • Explanation of the previous meeting's discussion on whether we need additional vacuum for quads?
    • Josie's optimised position for 4 quads fit within the 0.975m distance from source to vac tube but require smaller drifts than currently possible. The optimisation had space up to 1.4m so including more space would not change this it seems?
    • However, it is likely we will need more space to fit all the drives in.
• Funding Updates
  • Josie has a small fund that might pay for a set of dipoles
  • Colin and Ken have a thread about the end of year money
  • Deadline to spend the infrastructure fund is 31st March - can extend to June
  • Should cost systems with 4 or quads and a chicane as well

4. Bio EM,JP,MB:

• Actions Checklist
  • MB/EM: Send and evaluate the cells
    • Cells not sent yet.
  • EM, JMcG: Write up summary of PoPLaR Phase 2, including technical summary of cell irradiation procedure
    • STANDS
  • EM: Share the counting software she uses with Marie
    • STANDS
  • MB: Comet analysis
    • STANDS
  • CD: Tell Emma the min and max dose seen on the cell dish
    • DONE
• General Updates
  • Emma on the Causes of Cell Issues
    • Biggest issue is the time taken to irradiate. (Was 1-1.5hrs in phase 2)
    • Can get the time between shots to possibly 1 second and easily a few seconds
    • Removing the need to shoot RCF after would signifcantly reduce the time as well
    • Add a temperature sensor to see how stable it is

5. Beamline Diagnostic, KL, TP, CD, PH:

• Actions Checklist
  • EM/ED/LJ: Send calibration films to SCAPA and scan them in both orientations
    • STANDS Leaving Birmingham today
  • AFr, DA: Write out RCF procedure document
    • STANDS Diaza will finish before the next meeting. Share it around once complete
  • CD, TP: Evaluate LET in the cells with the RCF in front
    • STANDS
  • Unassigned (CD): Use sim to answer how many protons per shot in each fibre
    • STANDS Urgent
  • RW, ED: Tell Peter the dimensions of the vacuum chamber
    • DONE
• General Updates
  • Peter Latest Update
    • Best to avoid active components inside the chamber
    • Need a good understanding of the background effects since the fibres will be in the chamber and naked
    • Peter simulating a real scintillating fibre: Slides
      • Can increase the power received by coupling to another fibre. Saw little impact from lateral or angular offset in the second fibre
      • Critically missing the typical light produced per fibre per typical pulse NEEDED
  • RCF Update
    • Mark left 5x delaminated EBT3 in Birmingham.
  • Tony in talks with NPL about a potential non-destructive dosimetry capable of ns/Gy - do simulations indicate it is possible?

6. DoNM

• Tony can no longer do Thursdays 2-6pm due to teaching commitments
  • Suggest moving the meeting day
  • Previous polls indicate that 10-12 on Monday is the best time?
  • Emma noted that Tony can only do 1-3 ish on Mon, Weds and Fri so unfortunately unlikely to find a time everyone can do based on previous polls
• 3rd Feb Confirmed at 14:00

7. AoB

• Register for CP4CT workshop (27th Feb)
• Colin is possibly organising for LhARA to be at the Glasgow Science Festival (June 2026)
• Ken planning a session of radiobiology rather than just PoPLaR since want to encourage a broader discussion including ELIMED and Birmingham radiation plans
• ELIMED are doing a workshop in March possibly have to sign up today: ​https://indico.eli-laser.eu/event/229/

Summary of actions required

Phase 2 Analysis

• EM, MB: Organise transport of cells to Birmingham for evaluation
• EM: Evaluate the cell results
• CD, AFr: Complete analysis of RCF with errors
• EM/ED/LJ: Send calibration films to SCAPA and scan them in both orientations
• EM, JMcG: Write up summary of PoPLaR Phase 2, including technical summary of cell irradiation procedure
• EM: Share the counting software she uses with Marie
• MB: Comet analysis
• CD: Tell Emma the min and max dose seen on the cell dish

Beam Diagnostics

• AFr, DA: Write out RCF procedure document
• Unassigned: Find all the errors associated with RCF
• RW, CD: Study correlation between laser diagnostics and mean dose
• CD, TP: Evaluate LET in the cells with the RCF in front
• RW, ED: Tell Peter the dimensions of the vacuum chamber
• CD: Use sim to answer how many protons per shot in each fibre

Improve Bio results

• EM, JP: Discuss cell line to use next time?
• Unassigned: Obtain an inverted microscope

Long-term

• CD, JMcG: Investigate how to achieve uniformity without a scatterer in place
• KL, CW: Cost 4 or 6 quad, and chicane systems

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