General Meeting Summary 4/18/19

DISCUSSION OF DRAFT TALKS

TANJA

• Make clear what the scope is - point out subsystems that will be discussed in subsequent talks
• Make clear that detector consists of an array of 30x36 crystals and outer layers only catch showers - full acceptance is 25 msr
• Make clear that DVCS and SIDIS run together as a run group

STEVE W.

• Make clear what the scope is - point out subsystems that will be discussed in subsequent talks
• Make clear that detector consists of an array of 30x36 crystals and outer layers only catch showers - full acceptance is 25 msr
• Owner, maintenance, control: add list of collaboration responsibilities
• Magnet:

• no technical correctors - Steve L. will show detector details
• if magnet comes close to beamline, need to worry about impact on beam steering - Jay will show impact on beam

• Radiation levels:

• add that only small tasks to be done in hall during run (bolt on/off shelf from platform)
• add Hall A/DVCS as example of level of anticipated additional activation

• Documentation:

• NPS detector access need harness
• access to platform covered by standard hall operation documentation
• need OSP for experiment operation of NPS magnet
• add NPS airflow check to checklist

STEVE L.

• Downstream beam pipe: make clear that the minimum scattering angle in the beamline will not change

• changes in upstream part of the downstream beamline do not change the critical angle of the present Hall C small angle beam pipe

• Installation Schedule: add magnet testing - Charles will provide input on need for testing on floor or in place
• If possible, include downstream beam pipe in plot shown on page 11

CHARLES

• Include details on plan for mapping and running magnet
• Include details on safety and operation - OSP
• Add impact on optics - see Bogdan/Rolf slides from 4/4 meeting

CARLOS

• Anticipated timeline
• Add alignment requirements, e.g. survey points on frame taking advantage of carbon structure
• Add crystal and PMT info - Vladimir and Tanja can provide info

• Expected number of crystals and PMTs
• Final layout

• Add plan for HV dividers - Vladimir and Alex S. can make plots from recent beam tests
• Include required manpower - time requirement and match with collaboration resources

BRAD

• Add details on manpower requirement for firmware, e.g. fast electronics and Hall C
• Add details on slow controls (LED and cooling) - Carlos can provide information, templates available from Hall D prototype tests
• Near term analysis requirements - in Julie's talk

• estimated data volume
• on site (farm) vs. offsite analysis - will do onsite to allow more collaborators access to data
• distribution between Hall C cluster and farm

• Support for test/calibration on floor
• Block occupancy - estimate of 75 blocks is good within factor two based on Hall A DVCS experience

JAY - slides look good

JULIE

• Add analysis scheme - use hcana and load DVCS libraries

• works for HMS - load libraries as module, should not require major modifications
• currently have some support for waveforms, but might need development for fitting
• need to change decoder from DVCS to fADC

• Include Ho San's work on implementing Hall A library into Hall C analysis

• Ho San can send plots and figures

• Need to discuss what plots needed for online analysis during shifts - currently have root files and path for offline analysis of the waveforms

• aim that data are taken correctly and all waveforms are there

NEXT MEETINGS:

• THURSDAY 2 MAY at 9:00 AM (ET)
• DRY RUNS ON THURSDAY 9 MAY