General Meeting Summary 10/20/22

PARTICIPANTS: Arthur Mkrtchyan, Mark Jones, Carlos Munoz-Camacho, Tanja Horn, Charles Hyde, Fernando Barbosa, David Hamilton, Aaron Brown, Brad Sawatzky, Bogdan Wojsethowski, Alexandre Camsonne, Rolf Ent, Pramita, Yeran Ghandilyan, Arshak Asaturyan, Hamlet Mkrtchyan, Marie Boer, Vladimir Berdnikov

HV DIVIDER ISSUE - RESOLVED (Brad, Fernando, )

• Identified source of noise: unterminated bases

• Tested bases with modified filter on front end - mixed results
• as part of testing made interesting observation: if plug in more adjacent bases (terminated) then oscillations seem to disappear
• went to installed NPS columns to check if see oscillations are there and they are not!
• so far no noise on four columns installed in NPS

• More on source of noise

• it is a self-feedback and oscillation - unterminated bases/supplies might have been pushing noise into the system or perhaps there is cross-talk between adjacent bases that are not terminated
• goes away when plugged into any terminated device (e.g., a scope, fADC250)
• more technical details:

• have feedback loop and no resistor in circuit with it
• now if one does not terminate, but has a short at the output then the feedback loop will try to compensate for that
• if one has 0 V at input and makes a perturbation at the output then the preamp in the loop responds to that 0 V (with no termination), but then there is no place for the perturbation/charge to go and the perturbation at the pre-amp, which then goes to the input causing the oscillations/reflections
• regarding the size of oscillations - have 2inch from chip to output connector - determines the characteristics of the oscillation

• Overall conclusion: pre-amps need to be terminated!

• Path forward: Continue with plan for the PMT installation (as it was in August 2022) - be vigilant and look out for the noise

• Note: f250 blind to oscillations at high frequency - check with oscilloscope with high frequency response

ASSEMBLY ACTIVITIES

• Problem on LV supply (+-3V to bases) - MPOD bases

• seems current limited below where it should be (limited at 2A, should be 10A)
• Action item: Fernando will look into it
• not an issue in general for proceeding with assembly

• Still have to look at impact of noise mitigation of shielding the entire detector box

• planned for this week

• Status of the DAQ - can we take cosmics now?

• in principle yes - should be all set up, already checked response of fADC250
• plan to take fADC data by the end of the week

• Good progress with NPS cabling.

• the team at the moment: Hakob, Pramita, Yeran
• Glasgow team (Rachel, Tony) arrives early next week and can help with the cabling as well

• IJCLab-Orsay team update:

• shielding installed
• thermal sensors
• more cabling installed
• plan to finish cabling in the next few weeks

DSG UPDATES (Aaron)

• Status of the various projects in response to questions from last meeting

• Phoebus HV GUI - needs instructions on how to install
• Chiller controls - working on finalizing instructions
• Thermal monitoring control
• Humidity control - work in progress - should be done in less than 3 weeks
• LV controls software - expect to be complete in ~3 weeks
• LED controls - work in progress - missing software drivers; Phoebus screens are being developed

• Overall need ~3 weeks (+1 week for missing software drivers between VME LED drivers and the Phoebus screen) to complete all the items above

• Action item: prioritize to finalize the slow control items as planned

• Note that these items need to be completed as soon as possible (critical path) to make sure all pieces are lined up for the NPS checkout - in particular the LED drivers will be needed in the near future though the calo tests can start without them

• Phoebus Controller will be NPS/Hall C owned - emphasis on having backup for the device

• Software version control - how is it controlled?

• HV GUI - channels may swap around over course of time - typically do that in GIT and have experts and users using software; avoid that developers and users work on same version at the same time
• especially important for Phoebus based controls
• Action item: make arrangement in GIT for this - lower priority than finishing the instructions and rolling out software

SOFTWARE/DAQ (David H)

• DAQ and software setup on cdaql3 should work

• Waiting for cosmic data to further debug, test, etc.

MECHANICAL (Paulo)

• beamline will arrive within a week

• cable tray layout complete - delivery within a week

• Action item: need to test cable dolly

• all that is left: beamline support

READINESS REVIEW 2023

• See the following link for the stages of experiment readiness reviews: https://www.jlab.org/physics/experiment_process/np-pfx-chart

• NPS is now in phase N3
• NPS nominally on schedule in July 2023 - no delays foreseen at the moment

• Preparing things:

• planning schedule - personnel list for installation and how they interact with Steven L and Paulo
• check opportunities for collaboration to contribute
• how many people on site in March 2023 - July 2023

• Action items:

• submit beam time request for neutron part (Carlos)
• Ask Steven L to present/review installation schedule in next meeting

NPS COLLABORATION MEETING

• Next collaboration meeting: tentatively 2 February 2023

NEXT MEETING: 10 NOVEMBER AT 9:00AM ET