1. Kenny Walaron University of Glasgow / RAL
Beamline PID
Kenny Walaron
University of Glasgow / RAL

2. Scintillators At present absolute rate from target is poorly known
Essential to measure this, implications for detectors further downstream.
Best (Cheapest) way to do this is to measure rate with scintillating hodoscope detectors.
Must investigate optimal locations

3. Proposed locations

4. Code Can place polyethelene scintillators along beamline.
Need to model ionisation energy loss as particles traverse the medium.
Currently cannot be done with G4Beamline
Current virtual planes (Ascii detectors) produce a line of code for every particle passing through the plane.

5. Changes to Code First step
Implemented PDG Bethe-Block for each of the particles traversing the Ascii Detector.
Calculates and adds to the output file dE/dx
Obviously not proper way to do this.
Nasty and hardcoded

6. Changes to Code Cont. Hardcoded for Protons, Muons and Pions
Hardcoded for 1cm of Carbon
Only <dE/dX> calculated
Other physics processes e.g. production of delta electrons not catered for
Just wanted to have a look at such plots and check that it is feasible that we can differentiate between particles at this energy

7. Plots z=10mm

8. Z=6500

9. Z=15011

10. Z=17000

11. Summary of Plots Plane Protons Pi + Mu + Z=10 99956 45 Z=9000 59822
100 Pi+ created at target
Plane
Protons
Pi +
Mu +
Z=10
99956 45
Z=9000
59822
5385
Z=15011
139
6677
2617
Z=17000 23
2172
1291

12. Conclusions
Evidently not proper way to do things and was never meant to be
Need G4 implementation
Tom Roberts says this might not be straightforward. I don’t really know anything about inner workings of G4, mainly just a user.
My way does confirm that Proton/Pion differentiation should be possible. Theoretically this should have been the case but its nice to see the pics that confirm this.