General Meeting Summary 9/30/21

PARTICIPANTS: Aaron Brown, Alexandre Camsonne, Arshak Asaturyan, Fernando Barbosa, Brad Sawatzky, Carlos Munoz-Camacho, Charles Hyde, Hamlet Mkrtchyan, Julie Roche, Marie Boer, Paulo Medeiros, Emmanuel Rindel, Rolf Ent, Stephen Wood, Vardan Tadevosyan, Vladimir Berdnikov, Tanja Horn

HV DIVIDERS (Fernando)

• Final tests performed, e.g. to check the baseline noise

• noise was dominantly from darkbox - will verify with additional tests on a different dard box, but no showstopper anticipated

• Next steps progress correlated with low voltage cabling - need to add a connector to PCB, so need final decisions on that

LOW VOLTAGE CABLE STRATEGY (IJCLab-Orsay Team)

LV CONNECTOR AND CABLING

• Several different options for cabling investigated and evaluated

• Final decision: Add additional connector to PCB and add flat cables

• Two options for the connector: pin (six pin) connector or surface mount - have identified a pin connector, but not surface mount

• Action items:

• review connectors and identify a surface mount connector, if none available proceed with the pin connector
• proceed with adding the connector to the PCB

ADDITIONAL GROUNDING

• Motivation for additional grounding: noise reduction

• Electrical grounding - already have good grounding between mu metal and PMT block

• Options for adding additional grounding between mu metal tube and aluminum block PMT support

• picoflex connector with pins (can be disconnected)
• solder pad (permanent)

• Discussion of the grounding connectors

• Pin solution may allow for making decision later if want to use additional grounding or not
• On the other hand, have to make decision before assembly anyway

• Global grounding already exists - or already being worked on

• isolate chassis from detector - i.e., overall grounded block
• PMT blocks are already well grounded
• internal to chassis: if good connection PMT and chassis then should be ok

• Action items:

• Prepare scheme of global grounding scheme, general ground and localized ground

MECHANICAL (Paulo)

• Cable layout design ongoing

DSG UPDATES (Aaron)

• Crystal thermal simulations

• No heat load applied - temperature along crystal very stable

• Applying 3.5 W heat source (18degC central crystal)

• most heat dissipated in first 2cm
• specifications on temperature stability and uniformity - overall stability is more important than uniformity, e.g., can tolerate few degree difference in temperature at end of crystal

• Action item:

• complete additional studies, e.g., scale up to full detector size

REFLECTOR PRE-SHAPING

• Reflector pre-shaping is taking place at two sites: ODU and JLab

• both sites use the same shaping tools
• Ovens and annealing procedure are slightly different
• Initial foils prepared at ODU seem consistent with those prepared at JLab, but need to verify

• JLab oven has been used by another group on 9/29 - need to check availability of oven

• Action items:

• ODU provide details of the annealing methods used for the initial foils for validation of the procedure
• Find out groups that use the JLab oven

NEXT MEETING: THURSDAY 28 OCTOBER AT 9AM ET