July 31, 2020:

• Hall B put into beam permit. The plan is to take beam to tagger dump tonight and send to Faraday cup during day shift tomorrow.
• Shifts begin tomorrow at 8 a.m.. We are ready to resume RG-F!

• Dealt with vacuum issue in the upstream beamline. Everything is now pumped down without issue.
• Final DAQ checkout complete - ready for the run.
• MCC completes hall beamline hot checkout.

• Ramped torus and solenoid to full field for final checkout. All went well.
• Completed a series of cosmic runs for the RTPC as different solenoid fields to check the response.

• Completed final checkout of the RICH detector.
• Finalized trigger configuration file for run.

• Completed RTPC cosmic ray studies with solenoid at 500 A (1 T).

• Power up torus and solenoid to 500 A to continue checkout before ramping up to full field. Will leave on for the weekend.

• Investigating vacuum degradation and cryogenic instabilities in the solenoid that began last night.
• CVT cart was pulled upstream from the solenoid to investigate noise associated with several cables. Seems to appear when inserting cart in solenoid. Investigation begun.
• Identified issue with RTPC absolute pressure transducer.
• Completed magnetic sweep for the torus and solenoid magnets and marked field boundary in preparation of energizing the magnets for testing (possibly tomorrow).
• Pedestal run for FMT looks good. System is ready for beam.

• The RTPC and FMT detectors were moved into the solenoid in their final position.
• Took cosmic ray data on the RTPC checkout.

• Installed FMT on the downstream end of the RTPC and cabled it. An FMT pedestal run was completed. The FMT gas is now flowing.
• HV testing of the FMT completed.
• BONUS central detector installation and cabling complete. Ready to install into the solenoid.

• Finished preparation of two RG-F target straws now with 30 micron thick windows (instead of 15 micron thick of the old straw).
• The first straw tested fine with no leaks. The helium extension tube was attached and clamped in place.
• Completed high voltage checkout of the RTPC after installing the new target straw. All checked out good.
• Recabled the RTPC after the completion of the target straw replacement. Completed a pedestal run to check that there are no cable disconnects.

• Work continued on preparing the new RG-F target straws.

• Removed the FMT for checkout of the leaking target straw.
• The target straw was removed and found to be leaking at the upstream window.
• The plan is to build two new targets with thicker window over the next several days.

• Replaced the beam offset monitor PMT with the broken pin and the BOM is now working.
• Target straw leak confirmed at a rate of 2 psi/min when the straw is isolated from the supply and return.
• Took cosmic run for Forward Carriage/Drift Chambers to verify that DC readout is working with new DCRB firmware.
• Tested the spare target straw and it failed completely (window blew out during the test).
• Made decision to replace the target straw. Took down the upstream beamline and pulled back the RTPC cart from the solenoid. Unplugged cables to give access to gas feed line to target

• Performed cosmic run for RTPC
• There seems to be a leak in the target system; investigations are underway
• Trouble-shooting of beam offset monitor that was not counting; found problem with a pin connection

• Connected the target gas line
• Started flowing HeCO2 in RTPC
• Tested the target straw
• Check motors of beamline devices (harps, collimator, beam blocker) and checked their calibrations
• Checked halo counters (validated at HV)
• Troubleshooting beam offset monitor
• Tested new version of DCRB firmware; updated all DCRB crates

• Magnet Group completed initial checkout of the solenoid magnet power supply and interlocks
• JLab Survey and Alignment Group checked positions of BPM, harp, and beam pipe

• JLab Survey and Alignment Group aligned the RTPC/FMT detector to the beamline in its installed position in the solenoid.
• The beamline was assembled and pumped down to vacuum
• The tagger and Moller polarimeter magnets were tested and are ready to go
• Completed the maintenance on the RICH compressor
• Magnet Group completed initial checkout of the torus magnet power supply and interlocks

• Connected RTPC to gas and checked that flow behavior is comparable to what was seen on the floor (so leak rate checks good)
• Cabled up RTPC HV and temperature sensors. Applied HV to RTPC with He-CO2 gas mixture - the system checks good
• All FMT services connected, LV is on, and flow differential is good (i.e. the leak rate is good)
• Completed RTPC pedestal run and FMT pedestal run
• Took cosmic data for DC

• The JLab Survey and Alignment Group completed the as-found survey of the FMT
• The RTPC support/installation cart was craned from the floor of Hall B to the target level of the Space Frame and the gas panel was installed and connected

• The FMT has been mounted on its support tube downstream of the RTPC on the floor of Hall B. The signal, HV, ground cables, and gas lines have been connected.

• Replaced three ECAL ribbon cables between discriminator and TDC that were causing problems in TDC distributions in S1 and S4.
• The FMT support tube was installed on the end of the RTPC. The readout was given a full checkout and several cables that became disconnected during the FMT tube installation were reseated. All pedestals of RTPC measured. Now ready to attach the FMT.

• Working ongoing to debug some problems with the DAQ

• Completed second cosmic run for Central Detector after adjusting CND discriminators
• Completed final leak checking of the RTPC using He/CO₂ mixture. Now done sealing the detector. Ready to install the FMT tube.

• Applied final silicone sealing for gas leaks on the RTPC; leave overnight to set up.
• Electronics retested after applying silicone - all looks good.

• Tested the RICH compressor
• Changed CO2 dewar for the DC gas system
• Took Central Detector cosmic run for CTOF and CND after connecting trigger cable
• Tested electronics and connections for RTPC

• Connected RTPC to readout electronics for checkout. Issues with LVPS interlock need to be resolved for testing to proceed.

• Purified gas in LTCC S3 and S5 without going through the buffer tanks. The buffer tanks will be processed next.
• Begin connecting RTPC to readout electronics to allow for cosmic testing.

• Transferred RTPC electronics from EEL building to Hall B for testing of the RTPC after leak repairs.

• Leak checking of RTPC shows same leak rate as yesterday afternoon, even after additional epoxy sealing. Work to investigate the leak source remains in progress. At the end of the day, the output bubbler showed a bubble once every 3 s at an input flow rate of 200 scm, which is considered acceptable. The adapter boards were plugged back in after drilling out a few connector holes that had some inflow of epoxy.
• Begin preparations for electrical testing of the RTPC for early next week.

• Work on sealing the leaks in the RTPC continue. Additional epoxy applied and tests show improvement. Now output bubbler shows bubbles at input of 250 sccm. After a final round of epoxy sealing for the day, it was left to cure overnight.

• Tested leak-sealing on RTPC showed good improvement. After first round of sealing with epoxy, the detector bubbles at a flow rate of 350 sccm. The goal is to see bubbling at the output at an input flow rate of 200 sccm. Additional epoxy was applied at likely leak areas and left to cure overnight. More testing tomorrow.

• Attempted to purify some gas for LTCC S3 and S5, as well as the buffer tanks, to determine if the sectors are full of radiator gas. However, there was a problem with a faulty solenoid valves that will require some repair work.
• Opened buffer tanks to supply DC gas. This was the final step in the recovery of MEDCON6. The gas mixture in the chambers should be at the nominal ratio by the end of the week.
• Connected the gas panel to the RTPC for continued leak checking; the silicone used to attempt the first leak sealing of the detector was cleaned off and leak checking was repeated using H₂N₂ gas. Epoxy was applied to seal the leaking areas and left to cure overnight.

• The RTPC on its cart was moved to the floor to allow for better access for leak repair work to proceed. The FMT support tube was removed. Work began to prepare RTPC for applying sealant to the leaking seam area.
• Restored CTOF LVPS system for use with the shield compensation coils (still need to check functionality of interlocks and field polarity).

• Decided to move the RTPC off the beamline to the floor to allow for leak repairs. Today the detector was de-cabled and the gas panel was disconnected. Plan set up for Monday to move RTPC to the floor and start repairs. This will likely take most of next week.

• Work continued on the RTPC leak checking investigation. The leak is still present and options are being considered.

• Work continued on the RTPC. The leak checking today still revealed the presence of a leak where sealing was attempted yesterday. Additional sealant was applied and will be allowed to setup overnight.

• Checkout of FTOF channels requiring investigation after weekend cosmic runs; CTOF checkout for baseline PMT helium poisoning study before restart of RG-F.
• Worked to develop a tool to apply sealant to the BONUS RTPC seam where the He leak was detected. Applied sealer with tool and will wait for it to setup overnight.
• Replaced the power module for ECAL S5. HVPS tested fine. EC S5 now at voltage.

• Changed over the DC gas from pure argon to the nominal argon/CO₂ mix
• Leak tested RTPC and a leak is still present at the seam of the pad board - BONUS group notified

• Working on issues that occurred due to file server replacement (including fixing file server communications with VME crates and VTP boards). By the end of the day, all known problems were resolved and DAQ tested successfully.
• De-cabled and removed the FMT
• Work on leak checking of BONUS - found leak at helium tube endplate silicone joint and then resealed entire perimeter (now waiting for silicone to cure)
• Began to restore the DC gas system so next week nominal Ar/CO₂ can be set.
• Started Forward Carriage cosmic run (no EC S5 still)

• Began work on clonfs1 file server replacement in the morning. At noon Sergey reported the filter server was successfully completed on the CLON cluster and the most critical computers have been turned back on. In the afternoon some issues developed with the swap and investigations are in progress.
• Turned all readout crates on. DC LVPS on and communicating, CND CAMAC crate is on, LVPS for splitters is on, CTOF NIM bins on, beamline motors working.
• Turn on HVPS for FTOF, CTOF, and ECAL. There is a problem with EC S5 HVPS that needs attention.

• Begin restoration of the Hall B gas systems (DC, RTPC)
• Completed leak check of BONUS gas panel and external gas connections
• Moved RTPC installation cart upsteam to leak check detector at helium/CO2 flow of 400 sccm
• Leak found at downstream end of RTPC. After leak checking, reduced gas flow to 30 sccm

• Completed preparation of 5 HBList entries for upcoming work in/around Hall B - this includes one for the work in the EEL building to disassemble RTPC1

• JLab transitions from MEDCON6 to MEDCON5
• Bob Miller and Stepan Stepanyan are on-site to complete initial tour/inspection of Hall B and to discuss resumption of activities plan
• Begin preparation of HBList entries for upcoming work in/around Hall B