= LhARA radiobiology; meeting: 13Nov25; 14:00 BST =

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

Attended: EM, CD, JMcG, DA, TP, ND, MH

== Meeting Notes == 

1. Minutes and actions:
- **CW:** Contact Marie Boyd
 - **Done** Waiting. Probably worth waiting till we irradiate cells.

2. Strathclyde: BT, ED, RW, CD, TP, EM \\
- RW: Update on laser
 - Front quad is quite shiny so placed something in front to reduce reflection.
 - Changed around 5 separate things and now (fingers crossed) do not see the burning...
 - Ran 20 shots on Tues and Weds and saw no burning
 - Does mean not sure what caused it and could be any of the 5 things, including front quad being reflective...

- CD: Recap of experimental and simulated results
 - [raw-attachment: Slides]
 - Nick pointed out there is still a flaw in the comparison based on the number of particles reaching the final dish
 - Simulations producing similar shapes to experimental results 
 - Based on Highland equation for multiple scattering angle (from Geant4 documentation) predicted the different scattering effects
 - Mark has offered 2.5um Gold if we wanted to try that?
 - Cu 10um at furthest distance from second quad seems like a sensible option
 - If not uniform enough can move it closer
 - If we move it so the copper is 300mm from second quad then sims predict the dose will drop by 45% and the CV goes down by 6%
 - Robbie has a spare drive that we could use to play with this without pumping down the vacuum chamber each time

- RCF update: Plan to recalibrate
 - EM update on Birmingham calibration
  - Calibration Done - [raw-attachment: Slides]
  - 2023 batch is much preferred due to the framing we see around the edge of the darker batch
  - If we use the darker batch in the future cut only for the centre to avoid the framing
  - Calibration was also complete for some of the framed parts of the film to get some values for previously scanned work
  - Three sheets of the 2023 batch with Emma
  - I think there is more in SCAPA - Ask Ewan
 - KL/CD update on 2023 getting cut to 1cmx1cm:
  - Hopefully done by tomorrow
 - For future use best to buy a new batch and complete a calibration just before irradiating
 - Scanner Best Practices:
  - Place black cardboard around the RCF on the scanner to fix its position
  - Run 5-10 scans before scanning RCF to allow the scanner lamp to warm up
 - RCF Dose Calculation:
  - [raw-attachment: Slides]
  - Key Conclusions:
   - Scanner Best Practices:
    - Place black cardboard around the RCF on the scanner to fix its position
    - Run 5-10 scans before scanning RCF to allow the scanner lamp to warm up
   - An x by x median filter kernel should be applied to the dose map before calculating the flatness. Tony uses x=5.
   - A three channel correction could provide a more accurate dose than using one channel
   - Variability pixel to pixel? - Comes from the scanner resolution and is not indicative of low stats hitting each cell
    - 1 Gy means around 70 particles traversing the nucleus

3. BioPrep EM, JP: \\
- EM: Dry run outcome
 - Staining to be completed on Monday
- CW: Marie Boyd update
 - Wait till we have some cells irradiated
- Emma has to be in Oxford on Friday so cells need to be irradiated before then
- Possibility of extra days due to laser downtime? - Chat more about this on Monday

4. Simulation CD, DA, AFr: \\
- No update other than sims included above

5. Beam Diagnostics KL, CD: \\
- Real-time beam diagnostic update
 - Lanex tested in the beamline appears to work
 - Lanex behind the cell dish

6. DoNM 
- 27th Nov

7. AoB
- Josie viva - Completed it mate
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