Accelerator Update for June 18, 2008 - June 20, 2008

Wednesday June 18

The day shift began with Operations monitoring Tevatron (TeV) store 6228 (48.87E30) and the Recycler (RR) stash (163.2E10), with the Antiproton Source stacking (27.8E10), with the Main Injector, Booster, and Linac operating normally, with the Collider Detector at Fermilab (CDF) and DZero (D0) using the colliding beams, and with the SciBooNE / MiniBooNE (BNB) experiments taking beam.

At 8:37 AM, a MI RF station (MIRF1) tripped off. It reset.

A water expert reported at 8:39 AM that he was cleaning the MI-62 heat exchanger. The LCW pump was turned off to allow him to do this work.

The above pictures are of the MI-62 heat exchanger

TeV experts began an end-of-store collimator study at 11 AM.

TeV experts began an end-of-store separator study at 12:13 PM.

At 12:26 PM, the TeV suffered a low beta magnet quench at TeV sectors BA and BB.

Operations prepared D0 and CDF for access at 1:02 PM.

At 2:12 PM, a Linac Klystron RF station (KRF3) tripped off on a solenoid flow fault. It reset.

CDF and D0 were both out of access by 3:15 PM.

Operations put the TeV through a dry squeeze at 3:35 PM.

At 3:44 PM, the Linac buncher tripped off. It reset.

Operations reported at 3:59 PM that the Recycler had stashed antiprotons six times during the day shift.

At 4:04 PM, Operations reported that the TeV sector B48 separator would not change to the positive polarity. Operations contacted an expert.

At 4:06 PM, KRF4 tripped off. It reset.

TeV experts reported at 5:14 PM that the B48 separator must be locked so it can only run in the positive polarity. This will cause a HELIX alarm during injection, but the alarms will clear when the TeV starts to ramp.

At 5:15 PM, MIRF13 tripped off. It reset.

Operations put the TeV through a dry squeeze at 6:38 PM.

At 7:49 PM, KRF1 tripped off. It reset.

Operations put the TeV through a wet squeeze at 7:50 PM.

Operations established store 6232 at 10:10 PM with an initial luminosity of 278.5E30.

At 10:43 PM, Operations reported that a Linac quadrupole power supply (L:QPS106) had been tripping off. Operators swapped all of the supply’s control cards, but nothing improved. When they put the original cards back, the power supply began working.

Operations reported at midnight that the Recycler had stashed twice during the evening shift.

Thursday June 19

The midnight shift began with Operations monitoring store 6232 (184.8E30) and the stash (109.3E10), with Pbar stacking (44.3E10), and with BNB taking beam.

At 12:01 AM, BRF12 tripped off. It reset.

At 12:40 AM, a vacuum pump for BNB was found off. It reset.

At 3:11 AM, a Linac quadrupole power supply (QPS208) started making noise. Operators swapped out control cards until the problem went away.

At 5:33 AM, a TeV vertical separator at B11 sparked. The TeV lost about 41E30 of luminosity.

Operations reported at 7:56 AM that the Recycler had stashed six times during the midnight shift.

At 8:02 AM, the TeV store 6232 aborted at sector A2 due to an A2 power supply problem. There was no quench. Operators investigated and later discovered it had tripped on an overcurrent indication.

At 8:22 AM, cryo system experts reported that they were at the TeV sector A4 cryo building to investigate a problem with a helium sniffer.

TeV experts reported at 9:10 AM that they had found a bad +15 volt power supply on the ring overcurrent chassis.

At 9:24 AM, the Booster West Anode Power Supply tripped off. It reset.

At 9:28 AM, BRF3 tripped off. It reset.

A Recycler expert began, during a stash, a counterwave bump study at 9:54 AM.

An instrumentation expert reported at 10:24 AM that he was rebooting the MI DCCT.

Operations put the TeV through a dry squeeze at 11:17 AM.

Operations put the TeV through a wet squeeze at 12:01 PM.

Operations put the TeV into shot setup at 12:38 PM.

At 1:44 PM, the Linac low energy buncher tripped off. It reset.

MI and Recycler experts began study periods at 2:20 PM. Stacking had to be halted for the MI study.

At 2:21 PM, MI and LCW experts began a test; they turned off the MI-50 LCW and pond water pumps to see if the rest of the system could handle the added heat load. The old method of cleaning heat exchangers required the LCW system to be turned off. This test showed that only the local heat exchanger’s LCW pump needed to be turned off.

Operations established store 6235 at 2:40 PM with an initial luminosity of 265.14E30.

The MI study ended. Pbar resumed stacking at 3:10 PM.

The Recycler expert reported at 3:15 PM that he had completed his Electron Cooling drag rate measurements.

At 3:36 PM, a MI sextupole power supply (I:SEXVPS) tripped off. It would reset, but then immediately trip off again. Operations contacted an expert who adjusted the power supply’s trip limits.

Operations reported at 3:56 PM that the Recycler had stashed three times during the day shift.

Operations reported at 4:40 PM that they had run a special “Proton Load” timeline that manipulated the power supplies to put a big heat load on the MI LCW system and that the system handled it.

At 4:47 PM, KRF5 tripped off. It reset.

At 7:25 PM, the Pbar sweeper magnet power supply tripped off for the first of two times in 10 minutes. It reset.

At 10:36 PM, a Pbar Debuncher vacuum pump (D:IP712) tripped off. It reset.

Operations reported at midnight that the Recycler had stashed five times during the evening shift.

Friday June 20

The midnight shift began with Operations monitoring store 6235 (93.03E30) and the stash (237.1E10), with Pbar stacking (22.2E10), and with BNB taking beam.

At 12:46 AM, KRF2 tripped off. It reset.

At 5:01 AM, KRF5 tripped off. It reset.

Operations terminated store 6235 at 6:10 AM.

Operations prepared CDF for an access at 6:17 AM.

At 7:18 AM, a Booster vacuum pump (IPRF17) tripped off and caused BRF7 & 8 to trip off. Everything reset.

CDF came out of access at 7:43 AM.

A Pbar expert reported 7:58 AM that the sweeping magnet had no current reading. Operations reported that there was no alarm. The expert fixed the problem.

Operations reported at 7:58 AM that the Recycler had stashed five times during the midnight shift.

The Plans for Friday and the Weekend

The plans for today and the weekend are to stack, stash, and store.

Accelerator Update Archive

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