Meeting Summary Notes2022

INTRODUCTION

• In Experiment Table move item E12-06-114 ("DVCS days moved from Hall A") to position #3

• included in beam time request
• part of Phase 1, but was not part of ERR in 2019
• uses the same equipment

• Hall C planning process for the next few years is ongoing

• Mark has been talking to different groups and will try to make a decision soon

• Action item: Mark check with Patrizia Rossi to get formal approval for E12-06-114

MECHANICAL DESIGN AND STATUS

• Detector support structure - components in house and ready for assembly this SAD

• Cable support: method with support running underneath the SHMS platform

• Roof block cutting planned for this SAD

• time estimate - 2 weeks (checked with Walter)
• hole will be covered up with additional shielding

• NPS installation timeframes (expectation from Project estimates)

• HB removal - 2 weeks
• HB re-install - 3 weeks
• NPS initial install (SHMS right) - 50 days
• NPS removal from right side - 3 weeks
• NPS initial install (hardware) left side - 25 days
• NPS moved from SHMS right side to left side (looking downstream) - 1 week including 3 days of radcon cooling if immediately after a run
• Moving the sweeper magnet in same side setup will take a work day with survey support

• Discussion about ground during welding to protect detectors

• welding machines will be grounded to the hall floor

• Schedule for SAD - some concerns about physics starting in June instead of July

• Action items:

• check again if grounded signals/HV cables are isolated from the frame
• Mark check with Walter and Steven L. to make sure resources are available

DETECTOR SUPPORT GROUP

• Overview of all DSG projects completed and ongoing: HV cables and testing, ESR pre-shaping, hardware monitoring, hardware interlock system (ongoing), signal monitoring, software configuration, thermal simulation (ongoing)

• HV cables

• Fabricated 40 cables, need 30, so have 10 spare HV cables
• Estimate ~30 minutes for changing HV cables (turn off all HV in crate and unplug/plug)

• Crystal temperature depends on ambient temperature - may be of interest to have additional temperature sensors on the inside of the detector box

• discussion about where these would go - not much space inside the box
• cooling is outside the frame

• Action item:

• Make model for placement of the temperature sensors inside the box and figure out cable routing

HV DIVIDERS

• Completed studies and now procuring components

• hybrid approach to manufacturing

• Procurement complete in December 2021

• components
• LV cables
• PCB assembly

• Completion goal: originally 1 May (with delays 27 May 2022)

• one SAMTEC connector is late due to supply chain issues (current estimate is 9 March 2022)
• removed more than half dividers (from old PCB) and plan additional recources for socket installation to mitigate the impact of the delays and speed up how many dividers can be produced per week
• first dividers will be ready before March 27th and trying to further optimize
• plan to test every single divider with functional tests with LED

• Action items:

• Further optimize divider production - all dividers will be needed at the start of the assembly and stacking will take 1 week

SOFTWARE ANALYZER DEVELOPMENT

• Work has been completed to integrate DVCS into HCANA and infrastructure for fADC mod 10 has been implemented

• mod10 - oscilloscope trace around trigger time
• software can be adapted to obtain amplitude from trace

• Discussion about DAQ setup, HV, diagnostic tools for trigger setup test, LED, etc.

• need to define diagnostic histograms needed for cosmics tests
• set of histograms available - check what can be used

• Action Items:

• need firmware development
• need to implement event decoding in analyzer (VTP event unblocking)

CRYSTALS OVERVIEW

• All crystals are on site and ready for assembly

• Stacking strategy: all Crytur crystals

• Light yield measurement done with teflon and electrical tape wrapping

• Observe no difference in performance of crystals produced with old and new powder

• Discussion about crystal tracking

• goal: capture information for each module
• web-based spreadsheet for use during assembly
• database for longer term
• have experience from BigCal

• Crystal pre-shaping

• 700 pre-shaped foils are available
• 400 unshaped foils and tools are at JLab
• Completion goal: have all foils ready by the end of May

• Action Items:

• Collect information on what columns are needed for the web-based spreadsheet
• discuss with JLab about developing an Excel sheet with hidden columns etc.
• find out options how to turn the web-based spreadsheet into a database
• organize and carry out the shaping of the remaining ESR foils

CRYSTAL WRAPPING PROCEDURE

• Estimate ~1 week for 4 people to wrap all crystals

• 12 days for 2 people

• Pre-assembly tasks

• PMT+base assembly
• PMT kapton protection

• Assembly tools have been shipped to JLab and a step-by-step guide for the assembly is available on the Wiki

• Storage space for crystals needs to be checked and finalized

• see drawing from Brad's talk

• Discussion about monitoring module sizes

• Aim: monitor crystal size as modules are being prepared - do this row-by-row
• do not expect problems with fit as a carbon frame is used that defines the module compartments
• carbon compartments were made to accommodate the larger SICCAS crystal size - now that only Crytur crystals are used there should be enough space

TRAVEL AND ASSEMBLY IN CURRENT MEDCON 4 STATUS

• For international travel (if expect support from JLab) formal approval from DOE is needed

• timeframe: submit TA 45 days in advance of travel

• For domestic travel (if expect support from JLab) need formal approval from director and Site Office

• timeframe: submit forms ~2 weeks in advance - foreign nationals need to provide a CV

• Action Item:

• Send list of names of people planning to be on site for NPS assembly to Mark

DAQ, HV, CABLES, LAYOUT

• Components in hand, but some items need attention, e.g., cable bundling, software development

• Detector assembly layout in EEL

• crystal shelving holds ~300 crystals

• Action Items:

• Determine what would help for crystals storage

ASSEMBLY DISCUSSION

• Overall have a clear plan for the first 3 weeks for assembly - see the step-by-step guide and time estimates

• DAQ/electronics test specifics

• Aim: LED, cluter trigger tests
• need a coordinator (Brad?) and a DAQ expert to lead the setup, as well as participants

• Action Items:

• Make a step-by-step lust for the DAQ test specifics, e.g., cosmic tests, preliminary gain matching, etc.
• Identify a DAQ expert to lead the DAQ/electronics setup (LED, cluster trigger checking)
• Check with Jack Segal's group on cable patch panel and cable checkout