Agenda

Fluka optical response (photoelectrons) of pion detector to electrons, neutrons, photons, using the GEANT4 momentum-spectra for each particle type (Neven) [1]
New geometry of the lead donut with the rotated pion detector system- Blackening different faces of Lucite (Elham) [2]
Muon telescope setup at W&M (David) [3]
AOB

Attendance

David, Sudip, Neven, Elham, Wouter, Kate, Dustin

Fluka and GEANT4 seem to agree reasonably for PEs from electrons and gammas (given the spectra that GEANT4 predicts for what the pion detector sees using the Moller generator). The agreement is less good for neutrons, where Fluka seems to predict much smaller PE response than did GEANT4, but the good news is that in either case, the copious neutron flux is not expected to be a significant contribution to the PMT signal in the lucite. Fluka is probably a better estimate for the low energy neutrons relative here.

Comment - Perhaps we should move to the "precision physics list" for future GEANT4 simulations for the pion detector, to do a better job in particular with the low-energy neutron interactions

Elham has tried blackening various faces of the lucite using GEANT4. In agreement with Neven's earlier Fluka results, we see that the pi/e ratio degrades whenever we blacken. Optimum seems to be no blackening. Blackening seems to emphasize particular locations in the lucite.
Some progress on using the CAEN 6725 digitzer in external triggered mode.