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

Monday August 18

The day shift began with Operations monitoring the Tevatron (TeV) store 6364 (94.25E30) and the Recycler (RR) stash (267.2E10), with the Antiproton Source stacking (36.2E10), with Linac, Booster, and the Main Injector operating normally, with the Collider Detector at Fermilab (CDF) and DZero (D0) using the colliding beams, and with the MiniBooNE, NuMI, and the Meson MTest experiments taking beam.

At 8:16 AM, the Linac Klystron Vernier tripped off on a LCW flow fault. It reset.

At 9:17 AM, Operations reported that they had lost the ability to plot and had no t-clock or alarm information. The Booster accelerator was down and the operators could not see why. Controls experts investigated and found a bad power supply for the repeater cards. Normal operations resumed 10 minutes later.

At 9:20 AM, Operations reported that Booster was down due to a kicker’s (MP02) power supply. Booster experts replaced the power supply. Booster resumed sending beam about 10 minutes later.

At 9:38 AM, Operations reported that MP02 was causing more Booster problems. Experts investigated.

Booster experts reported at 10:42 AM that they had repaired an interlock issue with MP02.

At 11:05 AM, an odd alignment of beam out of Linac caused Booster and MI to trip off due to bad beam positions. Everything reset.

At 11:31 AM, Operations reported that the TeV sector A0 helium Dewar pressure was reading low. Cryo system experts and CHL took care of the problem.

A TeV expert reported at 12:18 PM that he was rebooting the TeV BLMs.

At 12:35 PM, MTest tripped off. Operators investigated and discovered that an interlocked beam detector had failed.

At 1:13 PM, the P2 transfer line beam permit tripped off due to a current drop on a quadrupole power supply (QF12).

At 1:38 PM, MP02 tripped off. Operations contacted experts. Booster resumed sending beam at 2 PM.

Operations terminated store 6364 at 2:02 PM.

Operations prepared D0 and CDF for access at 2:24 PM.

Cryo system experts began their repairs on the TeV sector E2 wet engine flywheel at 2:25 PM.

At 2:47 PM, Operations reported that an air conditioning unit used to cool the Main Control Room (MCR) developed a leak. FESS personnel and operators responded and turned off the unit.

The picture above shows what it looked like with chilled water shooting out of a 1/8-inch hole in a very old spigot. FESS repaired the leak.

Operations turned off the Linac beam at 3:05 PM so that Preaccelerator experts could access the H- Source and replace a power supply. Experts also worked on the cavity water regulation for KRF6.

Operations loaded an energy conservation time line into the Time Line Generator (TLG) at 3:08 PM.

At 3:39 PM, the TeV suffered a quench in E sector. There was no store or beam in the machine.

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

At 4:10 PM, a Linac quadrupole power supply (QPS225) tripped off. It reset.

D0 and CDF came out of access at 4:29 PM.

At 4:50 PM, the Linac Klystron Vernier tripped off on a LCW flow fault. It reset.

Operations put the TeV through a dry squeeze at 5:35 PM.

Operations put the TeV through a wet squeeze at 5:43 PM.

Operations put the TeV into shot setup at 6:44 PM.

Operations established store 6367 at 8:18 PM with an initial luminosity of 307.35E30.

At 9:16 PM, the MI South Anode Power Supply tripped off. It reset.

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

Tuesday August 19

The midnight shift began with Operations monitoring store 6367(170.64E30) and the stash (138.4E10), with Pbar stacking (31.2E10), and with the MiniBooNE and NuMI experiments taking beam.

At 1:59 AM, Operations reported that a MI RF station (MIRF2) had tripped off for the first of three times in about an hour and brought down the NuMI beam permit each time. Everything reset.

At 4:50 AM, the Linac Klystron Vernier tripped off. It reset.

At 4:51 AM, a Pbar Accumulator RF station’s (ARF4) VME was not responding. Operators investigated and then called in an expert.

At 6:34 AM, the Linac Klystron Vernier tripped off. It reset.

At 6:45 AM, Operations reported a problem with ARF1. Operators investigated and then contacted a Pbar expert. (Later they reported that the ARF1 problem was due to ARF4.)

Operations established beam to MTest at 7:30 AM.

Operations reported at 8 AM that the Recycler had stashed three times during the midnight shift.

An expert restored the TeV sector D1 BPMs at 9:59 AM.

Operations prepared Pbar for an access at 10:42 AM. RF and Instrumentation experts will adjust the notch filter in the Pbar Debuncher stochastic cooling. Mechanical experts will measure the kicker tank. Vacuum controls experts will add diagnostics to a beam valve (D:BV728) CIA crate.

A MI expert began a coalescing study and a Recycler expert began a cooling study at 10:43 AM.

At 11:10 AM, the Linac 400 MeV area beam permit tripped off for the first of two times in about 10 minutes. Coincidentally, KRF7 had a phase problem with each trip. Everything reset.

At 11:29 AM, BRF15 tripped off. It reset.

Pbar came out of access at 11:45 AM.

The MI study ended at 11:52 AM.

At 12:13 PM, LRF2 tripped off. It reset.

At 12:37 PM, Operations reported that the Switchyard CAMAC link was down between TG-9 and SSB. Operations contacted controls experts.

At 12:46 PM, the 400 MeV area tripped off. It reset.

At 12:56 PM, LRF4 and LRF5 tripped off. It reset.

At 1:04 PM, Operations reported problems with the antiproton production being down 50%. Pbar experts investigated.

Pbar experts began a destructive Debuncher cooling study at 2:26 PM.

At 3:20 PM, a cryo system expert reported problems with the TeV sector C4 reciprocating engine.

Operations reported at 4:01 PM that the Recycler had stashed three times during the day shift.

Operations disabled the MTest beam at 4:34 PM. This ended the T979 experiment for now. A new MTest experiment (T984) will begin on 8/20/08.

At 7:02 PM, the P2 transfer line beam permit tripped off due to a quadrupole power supply (I:QF12) output sag. Everything reset.

Operations terminated store 6367 at 7:33 PM.

Operations put the TeV into shot setup at 7:47 PM.

At 8:39 PM, LRF4 tripped off. It reset.

Operations established store 6368 at 9:15 PM with an initial luminosity of 300.52E30.

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

Wednesday August 20

The midnight shift began with Operations monitoring store 6368 (178.25E30) and the stash (97.3E10), with Pbar stacking (36.5E10), and with the MiniBooNE and NuMI experiments taking beam.

At 2:26 AM, the NuMI beam permit tripped off when a quadrupole power supply’s (E:QF107) output current sagged. Everything reset.

At 2:46 AM, the TeV sector B1 air compressor tripped off on low pressure. Operators reset the compressor.

At 6:07 AM, a Booster vacuum pump (IPRF17) tripped off and caused BRF7 & 8 to trip off. Everything reset.

Operations reported at 7:53 AM that the Recycler had stashed five times during the midnight shift.

The Plans for Wednesday

The plans for today are to terminate store 6368 at noon and then let the cryo system technicians begin replacing the TeV sector C4 cold compressor. This job will take from 6 to 8 hours. The Run Coordinator will allow certain jobs to take place during the cryo work.

Accelerator Update Archive

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