General Meeting Summary 5/10/18

DISCUSSION TCS SETUP (Vardan)

• General description: polarization in horizontal direction, two calorimeters and detectors stacked vertically (vertical polarization and side-by-side detectors not possible due to target properties), currently assume g2p target scattering chamber

• In simulation place loose cuts for apertures and see where events of interest go

• Results:

• Reasonable acceptance, can get 10-20% detection efficiency
• can optimize hodoscope
• need to optimize trigger to handle background - coplanarity scheme?

DISCUSSION TCS PHYSICS CASE (Marie)

• Here assume few percent acceptance (would gain additional statistics if using Vardan's result), 5% error on cross section, and evaluate impact of measurement on global GPD fits together with existing data

• Discussion about TCS measurement in context of already completed experiments, e.g. neutron

• need to measure both for flavor composition
• include impact of these measurements on deuterium in uncertainties with caveats about differences

• Discussion about physics case in context of leading twist and leading order

• Discussion about if material sufficient to proceed with full PAC proposal this year

• Could consider an LOI since made much progress with more worked out concepts since 2015 and can demonstrate that experiment doable - if decide to proceed this way need draft to group for feedback before 17 May
• In general, main aspect to work out for full proposal: show that can handle background

CRYSTAL STATUS UPDATE

• Update on email communications with CRYTUR about 450 crystal order

• Update on communications with SICCAS about current order and possible crystal replacements

• Discussion about path forward

• near term: wait for official response from CRYTUR
• check in with Rainer

NEXT MEETINGS: THURSDAY 17 MAY AT 9:00AM (EDT), THURSDAY 31 MAY AT 9:00AM (EDT)