Accelerator Update for October 29, 2008 - October 31, 2008

Wednesday Oct 29

The day shift began with the Tevatron (TeV) in shot setup, with Operations monitoring the Recycler stash (38.7E10), with the Antiproton Source (Pbar) stacking (120.8E10), with the Linac, Booster, and the Main Injector (MI) operating normally, with the Recycler’s Pelletron down, with the MiniBooNE, NuMI, and Meson MTest experiments using the beam, and with the Collider Detector at Fermilab (CDF) and D-Zero (D0) waiting for the next store.

Operations established store 6528 at 8:13 AM with an initial luminosity of 81.51E30.

Operations reported at 9:48 AM that Pbar experts were beginning their studies.

A MI expert began a coalescing study at 11:21 AM.

At 11:33 AM, a Linac Klystron RF station (KRF1) tripped off on a transformer LCW flow fault. It reset, but then tripped off on a CS flow fault. It reset, but then tripped off on a RF leak detection. Experts reported that the Linac Klystron test stand was sparking due to a study they were running and this had caused KRF1 to trip on a RF leak indication.

Linac resumed sending beam at 11:51 AM.

At noon, KRF1 tripped off for the first of two times in six minutes. It reset.

Linac experts began a RF station study (LRF5) at 12:15 PM.

Pelletron experts reported around 12:15 PM that Electron Cooling had been restored.

A Pbar expert reported at 12:49 PM that they had completed their studies.

Pbar resumed stacking at 12:55 PM.

Operations prepared Pbar and the Pbar Prevault area for a 90-minute access at 12:59 PM.

At 2:19 PM, Operations reported that a Pbar power supply (H704) would not turn on. Operations contacted a power supply expert who brought it back online.

Pbar resumed stacking at 3:02 PM.

At 3:55 PM, the Pelletron tripped off due to a voltage drop. An expert investigated and reported that the voltage drop was due to a corona discharge in the gas. Operations reset the Pelletron.

Operations reported at 4 PM that TeV experts had begun an end-of-store study.

Operations reported at 4:03 PM that the Recycler had stashed antiprotons once during the day shift.

Linac experts reported at 4:39 PM that the LRF5 studies had ended and they had returned the station to its normal operating mode.

Operations disabled the MTest beam at 6:13 PM.

TeV experts reported at 8:42 PM that they had completed their end-of-store studies.

Operations terminated store 6528 around 9:14 PM.

Operations put the TeV into shot setup at 9:21 PM.

Operations established store 6529 at 10:49 PM with an initial luminosity of 215.07E30.

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

Thursday Oct 30

The midnight shift began with Operations monitoring store 6529 (158.88E30) and the stash (60.7E10), with Pbar stacking (25.8E10), and with the MiniBooNE and NuMI experiments taking beam.

Operations turned off the MiniBooNE beam at 5:56 AM in preparation for an all day access.

At 6:03 AM, store 6529 aborted at TeV sector C3. Operators investigated and discovered that the C3 vacuum had caused the abort.

Controls experts reported at 7:22 AM that they had replaced a ‘Fan-In’ box, a cable, a relay, and they swapped the valve control card with the sector C2 house control card.

Operations reported at 8:06 AM that the Recycler had stashed eight times during the midnight shift.

At 8:29 AM, the P2 beam permit tripped off for the first of two times in four minutes due to a power supply (I:HV12) tripping off. Everything reset.

Cryo system experts reported at 8:36 AM that they were working on the TeV sector D3 wet engine. When through with D3 the cryo experts will move on to E3 and F1.

Operations put the TeV through a dry squeeze at 11:01 AM.

Operations put the TeV through a wet squeeze at 11:50 AM.

Operations put the TeV into shot setup at 12:33 PM.

Operations established store 6532 at 2:14 PM with an initial luminosity of 293.58E30.

A LCW expert from CUB reported at 2:52 PM that he had brought column #1 online.

At 3:11 PM, KRF5 tripped off. It reset.

Operations reported at 4 PM that the Recycler had stashed six times during the day shift.

At 5:01 PM, LRF5 tripped off. It reset.

Operations disabled the MTest beam at 6:14 PM.

At 7:50 PM, LRF5 tripped off. It reset.

At 8:31 PM, Operations reported that the Pbar Lithium Lens had tripped off for the first of two times in one hour and 45 minutes. It reset. Operations contacted an expert.

At 10:23 PM, LRF2 tripped off. It reset.

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

Friday Oct 31

The midnight shift began with Operations monitoring store 6532 (94.23E30) and the stash (228.3E10), with Pbar stacking (34.5E10), and with the MiniBooNE and NuMI experiments taking beam.

Operations terminated store 6532 at 5:25 AM.

Operations put the TeV into shot setup at 5:38 AM.

Operations established store 6533 at 7:08 AM with an initial luminosity of 316.74E30. (This was the second highest store luminosity. The highest store luminosity of 318.49E30 was set on 7/5/08.)

At 7:52 AM, Operations reported problems with getting beam into the Accumulator. Pbar experts investigated.

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

The Plans for Wednesday

The plans for today and the weekend are, in general, to stack, stash, and store. However, all plans are on hold until the Pbar experts discover what is causing the stacking problem.

Accelerator Update Archive

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