GEP software meeting agendas/minutes
From SBS wiki
Contents
GEP software meetings
| Name | GEP-1 | GEP-2 | GEP-2a | GEP-3 | GEP-3mod |
|---|---|---|---|---|---|
| (aka GEP-0) | |||||
| Beam Energy (GeV) | 6.476 | 8.588 | 4.359 | 10.688 | 10.688 |
| SBS angle (deg) | 25.7 | 22.1 | 28.5 | 16.9 | 18.6 |
| Central/nominal Q^2 (GeV^2) | 5.732 | 8.127 | 3.860 | 12.039 | 11.109 |
| ECAL angle (deg) | 29.46 | 27.27 | 35.0 | 29.75 | 27.0 |
| ECAL distance (m) | 8.0 | 6.0 | 5.0 | 4.7 | 6.0 |
| SBS distance (m) | 1.6 | 1.6 | 1.6 | 1.6 | 1.6 |
| HCAL distance (m) | 10.0 | 10.0 | 10.0 | 10.0 | 10.0 |
| Central proton momentum (GeV) | 3.881 | 5.185 | 2.845 | 7.294 | 6.794 |
| Central electron energy (GeV) | 3.422 | 4.257 | 2.302 | 4.273 | 4.768 |
| SBS magnetic field (% of maximum) | 53 | 71 | 39 | 100 | 93.1 |
| SBS BdL (T*m, central ray) | 1.28 | 1.71 | 0.94 | 2.41 | 2.243 |
| SBS current setting (A, (% of maximum)) | 851.3 (40.53%) | 1158.4 (55.16%) | 624.3 (29.73%) | 2100 (100%) | 1762.2 (83.9%) |
| Central precession angle (deg, rough) | 43.7 | 57.7 | 32.8 | 80.5 | 74.4 |
| epsilon | 0.733 | 0.720 | 0.691 | 0.616 | 0.676 |
| P_T | -0.068 | -0.044 | -0.114 | -0.029 | 0.001 |
| P_L | 0.674 | 0.692 | 0.707 | 0.787 | 0.737 |
Notes on the kinematics table (August 13, 2024)
- ECAL distance and central angle for GEP-2a are not yet finalized; need to optimize, check snout aperture, acceptance matching, etc.
- Nominal magnetic field settings are for nominal production data taking (optimizing acceptance/event rate). Some fraction of the data may be taken at other field settings to study systematics of SBS optics and spin precession. In particular, some fraction of the GEP-2a and/or GEP-1 data may be taken at the higher field settings relevant for GEP-2/GEP-3
- Central precession angle is calculated assuming a central field integral of 2.43 T*m for the maximum field setting.
- HCAL distance of 10 meters is assumed for all settings. It may be desirable to put HCAL slightly closer for the low-Q^2 settings, but coverage of the useful acceptance seems good even for those settings.
- Central kinematics (Q^2, proton momentum, scattered electron energy, etc) are calculated using the beam energy and the central SBS angle. The central ECAL angle may differ slightly for GEP-2a from the angle implied by the central proton kinematics and the beam energy. Need to check acceptance matching and vacuum snout aperture on ECAL side.
- For the modified highest-Q^2 point, I may have used a slightly different form factor ratio parametrization that happens to cross zero earlier to calculate the values of PT and PL
Useful documents/links
- Original proposal
- PAC47 (Jeopardy) proposal
- PAC52 proposal for "GEP+": PDF
- GEP software "TO-DO LIST" and discussion: link title
Useful links for analysis/experiment running
Agendas and Minutes
We are collecting meeting agendas/minutes/links to slide shows here for the time being. The meetings are currently Mondays, 1:00 PM. Subscribe to sbs_software@jlab.org for announcements/updates.
Tuesday, August 6, 2024 (no meeting was held)
