LhARA radiobiology; meeting: 17Dec25; 12:00 BST

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

Attended: CD, PH, AFr, MB, RA, KL, EM, HO, JP, MH

Meeting Notes

1. Minutes and actions:
   • MB/EM: Evaluate the cells
     • STANDS
   • CD, AFr: Complete analysis of RCF with Error Calculation
     • STANDS (Waiting for Orientation Scans)
   • EM/ED/LJ: Send calibration films to SCAPA and scan them in both orientations
     • STANDS
   • AFr, DA: Write out RCF procedure document
     • STANDS
   • EM, JMcG: Write up summary of PoPLaR Phase 2, including technical summary of cell irradiation procedure
     • STANDS
   • RW, CD: Study correlation between laser diagnostics and mean dose
     • STANDS
   • CD, TP: Evaluate LET in the cells with the RCF in front
     • STANDS
   • CD: Compare dose profile consistency
     • DONE

2. SCAPA RW,ED:

No Update

3. Bio EM,JP,MB:
   • See cells in FaDu from all days and the higher seeding densities.
     • Seeing a clear dose response.
     • Still looks like the radiation has been too high.
   • No cells in HeLa.
     • Seem to be more sensitive.
     • Emma mentioned that people working with them in Birmingham at the same time as phase 2 were struggling to get results with them. So could be the cell line? However, since Emma has got back she has done more work with them and they seem fine?
     • Possibly worth moving to a different cell line in the future?
   • Cells back with Mark and he will organise their delivery to Birmingham. (Most likely after Christmas)
   • Results hopefully can be produced by end of Jan
   • Marie is keen to stay connected. She is putting together a grant about different radiation types so this work is all useful.
   • Emma to share the counting software she uses with Marie
   • Still uncertain about the uniformity.
     • Comet analysis should help with this
       • But cells were on ice for a while before being forzen so may have repaired.
     • Calvin to send Emma min and max dose

4. Beamline Diagnostic, KL, TP, CD, PH:
   • RCF Update
     • RCF not sent up yet, so will send in Jan
   • KL, PH on Sparse Sci-Fi Slides
     • Peter has a simulation of the fibres used (50mm long fibre polysterene core and PMMA cladding as per BCF50)
     • If using a remote camera recieve order of 1/1000 power from scintillation as if using a nearby screen.
     • Key questions: 1) What is the typical light produced in a sparse fibre per laser pulse
       • How many protons per shot pass through each fibre
         • 20-30 is fine but 1 or 2 is too few
       • Can be done in sim but requires a better understanding of the source distribution
       2) Dimensions of the vacuum chamber
     • Instead of remote could also looking at capturing the light into a larger fibre to collect more light
   • Phosphor screen requires face-on viewing so possibly some practical difficulties
     • Peter also happy to simulate this
   • Using the discarded beam (Photodiode).
     • Beam consistency shows a Pearson Correlation Coefficient of minimum 0.83.
     • Predicting the average pixel count inside the cell dish from the beam outside the cell dish provides a Pearson correlation coefficient of 0.991, and can predict with a 6% error.
     • Better analysis to be done with dose once RCF properly calibrated
   • Delaminated RCF
     • Mark Hill has some and will take it to Birmingham tomorrow.
     • Will need to do a calibration of this before we start a new run
     • Least popular option

5. Lessons Learnt and Aims for Timeline, CD:
   • Critical issues are:
     • Beam uniformity
     • Shot-to-shot variation
     • Control Survival
   • Plan for next run (minimum requirements):
     • Repeat of phase 2
     • Move the scatterer forward to improve beam uniformity
     • Have an in-beam diagnostic
       • Minimum option is delaminated RCF
         • Requires calibration and full description of RCF errors
       • Hopefully test a sparse sci-fi
     • Reduce the time the cells are in carousel
       • Reduce time between shots
       • Make people aware of the importance of this
     • Use SCAPA as destination for immediate cell work
       • Require an inverted microscope
       • At the end of the week move the cells to Marie's lab for better control
     • Discussion needed on the benefits of doing this run?
   • Longer-term
     • Remove scatterer and introduce more quads
     • Introduce a dipole chicane
     • Use an X-ray control
     • Introduce a (pseudo-)beampipe
     • Look at ELIMED option
     • Permanent SCAPA beamline?

6. In-Person Meeting
   • Date: February (9th, 10th, 24th, 25th, 26, 27th are currently the best options)
   • Place: Strathclyde will be the default. Second choice would be Birmingham
     • Need to discuss further
   • lettuceMeet: ​https://lettucemeet.com/l/lWwgW

7. DoNM

• 8th Jan (Only if necessary to sort out deliveries etc) Emma to host

8. AoB

• Ken keen for support for Royal Society Exhibition
• Merry Christmas!!!

Summary of actions required (so far)

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
• Unassigned (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

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