[Hallc_running] [New Logentry] Status Update

[pooser at jlab.org]

Logentry Text:
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Production data continued to be collected during day, swing, and owl shifts yesterday.  The SHMS kinematic point of 29 deg and -3.7 GeV was completed and ~80% of the LH2 data was obtained for the SHMS at -3.0 GeV.  The beam quality was quite good during day and swing shifts however, the owl shift was plagued by separator issues.  

While the average RF trip rate yesterday was ~4 trips/hr, which is being revered as quite the accomplishment for the accelerator, the inability to sustain > 750 kW in the machine is not understood.  After the morning meeting MCC organized a meeting of the machine system experts in order to formulate a plan to shake out the systems which are causing the power limiting issues and develop a plan moving forward.

It was made clear this morning that beam similar to this past weekend will not be available during day shift today.  They will require Hall-C to act as a high current beam dump for the machine therefore, it is likely that no accesses to the hall will be possible.  However, if the machine encounters a hard down, then MCC will facilitate an access for work on the HMS dipole power supply.  The target has been moved to the home position and will remain there until MCC’s diagnostic work is complete.

Upon the conclusion of MCC’s work today, “production” beam will likely be made available during swing and owl shift tonight and we will continue with the F2 run plan.  The day shift leader is on stand-by. All other shifts are required to be fully staffed unless otherwise notified.

Special Requests:
Brad Sawatzky: DAQ buffer mode tests

Work completed in the hall during accelerator accesses:
Jack Segal: HMS Q2 power supply
Hall-C Techs: HMS dipole penning vacuum gauge

Special notices in effect for shift crews:
Recovering the HMS DAQ: https://hallcweb.jlab.org/wiki/index.php/Hall-C_HMS_DAQ_Failure_Modes
TO Instructions for LH2 <--> LD2 switches : https://logbooks.jlab.org/entry/3534487, https://logbooks.jlab.org/entry/3547019

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This is a plain text email for clients that cannot display HTML.  The full logentry can be found online at https://logbooks.jlab.org/entry/3548244
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