November 23, 2009 (11AM), Physics Working Group

Connect Information

ESNET and EVO will be available:

1. ESNET: 85-42553 (85-HALLD)

2. An EVO room under GlueX will be reserved

Agenda

Possible plan of action for evaluating the effects of a smaller magnetic field:

• 1. Scale the charged particle momentum resolution in HDParSim.

• 2. Update the acceptance tables in HDParSim to account for changes in geometrical acceptance.

• 3. Study the EM background levels in the FCAL, TOF, and FDC. The increased backgrounds will require either (a) running at lower luminosity (how much lower?), or (b) increasing the dead area of the FDC or widening the holes in the TOF and FCAL (how much wider?).

• 4. Assuming the central holes of the FCAL, TOF, and FDC need to be widened due to EM background, the acceptance tables in HDParSim would need to be updated.

• 5. Study missing mass resolution.

One possible study would be to see how much the background from:

gamma p --> pi+ pi+ pi- Delta0; Delta0 --> pi0 n

leaks into

gamma p --> pi+ pi+ pi- n

for different missing mass resolutions. The size of the background could be used as a measure of our sensitivity to an exotic wave (e.g. if the background from the Delta reaction is 10%, it becomes pretty dubious to fish out a 5% signal from the pi+ pi+ pi- n reaction).

• 6. Study the shapes of acceptances in Gottfried-Jackson angles for 3pi reactions for different magnetic fields.

• 7. Use the kinematic fitter and the TOF to see how much PID degrades with worse resolution (and a potentially larger hole in the TOF).

• 8. Perform a PWA on 3pi final states. (This might not be necessary if step 5 or 6 show unacceptable degradation).

• (work done by Pawel: File:Eta-sim-at-gluex-prot.pdf)