General Meeting Summary 11/10/22

PARTICIPANTS: Arthur, Hamlet, Mark, Tanja, Charles, Steven L. , Carlos, Paulo, Vardan Petr, Alexandre, Yeran, Bogdan, Rolf, Pramita, Julie, Bob Michaels, Deb, Brad,

NPS ASSEMBLY AND FIRST LOOK AT COSMICS

• First look at cosmic data for the four columns installed (Pramita slides)

• 25 events for one PMT, fADC window 400ns
• Cosmic rate
• Trigger: AND of two integrated Scin paddles
• HV on NPS crystals: 800 V (higher than experiment)

• Additional details on cosmic data in the NPS log (Brad)

• System is working
• 100k triggers (trigger made in NIM), 4mV threshold, selecting events for events going through entire detector
• average to get pulse profile for each crystal - out of 100k any crystal has ~1% chance for good cosmics pulse
• average pulse height ~10mV - noise on order ~1mV
• observe oscillations in some channels - might be cross talk, but needs more investigations
• HV channels - a few are problematic (over voltage) - need to keep track of and address

• Overall, the first test was successful and system seems to be working fine. Ready to cable up rest of the columns

• Temperature control and LED - in discussion with DSG - not yet ready to test

• Action item: continue working with DSG on this

• Cabling (Yeran)

Have bundled over 900 cables - 14 boxes to go

• Action item: need to get 14 additional boxes

MECHANICAL

• Cable management: tested cable dollies - all seems to work fine; will use that now instead of cable conduits

• tested with 240 cables (1/4 of all cables that will be used, cooling, LV cables)
• designed to work for both sides of the spectrometer
• moving cables still a major challenge - manageable, but need to plan
• Action item: check out GeP example where used dollies with three layers vertically - can it be used for NPS

• Water cooled corrector for pion beam setup

LOGISTICS

• Recent change in personnel: Vladimir (CUA) left and took a position at JLab; Brad (JLab) left and though still at JLab has new responsibilities that considerably limit his available time on NPS

• CUA hired a new postdoc (Yeran) who is stationed at JLab and part of her responsibilities is NPS; NPS collaboration has been having (additional) collaborators on site for various tasks over the last year (e.g., AANL, CUA, IJCLab-Orsay, OU, U. Glasgow, UIC), Brad has been continuing his support for NPS, but his cycles have been becoming more limited

• Overall, on-site organization for NPS is needed and becoming more important as going towards installation

• starting in March 2023 need collaboration representation at JLab for cabling/decabling etc. and other efforts to install the NPS; a good time period might be: April - mid-July

• Action item: separate meeting to discuss possible path forward for on-site organization

PREPARATIONS FOR INSTALLATION

• Beam time request for neutron DVCS has been submitted

• Final readiness review: no formal review format, review of documentation

• February 2nd, 2023: NPS collaboration meeting

• Review of the installation schedule (Steven L.)

• Installation schedule was reviewed by work coordinators and engineering
• No one sees a problem with it other than the delivers of the beam line corrector magnets and PSUs. Even those should have enough float to meet the July 7 startup date.
• The cable installation/connections and detector installation/checkout are swags and the collaboration should look has ownership of these items. Coordination of those items and time to finish them should be reviewed. DSG could not provide an estimate when asked about them.
• Need to identify additional tech help needed before moving NPS into the hall

• Action items:

• Start planning for final readiness review
• Identify if any additional tech help needed before moving NPS into the hall
• Tidy up endgame - note that the hook up of cables is planned for June (approximately 4-6 weeks before start of beam), which is a tight schedule

NEXT MEETING: THURSDAY 1 DECEMBER 2022 AT 9AM ET