Accelerator Update for December 5, 2008 - December 8, 2008

The Integrated Luminosity for 12/1/08 to 12/8/08 was 55.29  Pb^-1.

Friday Dec 5

The day shift began with Operations monitoring the Tevatron (TeV) store 6619 (161.5E30) and the Recycler stash (131.5E10), with the Antiproton Source stacking (20.8E10), with the Linac, Booster, and Main Injector (MI) operating normally, with the Collider Detector at Fermilab (CDF) and D-Zero (D0) experiments using the colliding beams, and with the MiniBooNE experiment taking beam. NuMI was down due to a horn problem.

At 8:53 AM, the Pbar Debuncher lithium lens (D:LNV) tripped off. Operations put Pbar into standby and contacted an expert.

MI RF experts turned off the South Anode Power Supply at 9:57 AM so that they could begin repairs on MI RF station #1 (MIRF1).

A Pbar expert reported that he replaced a fuse holder for the lithium lens power supply. Pbar resumed stacking at 10:22 AM.

At 10:33 AM, the P1 transfer line beam permit tripped off for the first of three times in 30 minutes. It reset. Operations restored a good autotune file.

At 11:39 AM, Operations reported that the MiniBooNE beam permit had tripped off three times. It reset. Operations notified an expert.

The Neutron Therapy Facility reported at 12:55 PM that they had completed treatment on their last patient for the day.

At 3:18 PM, MI RF experts reported more problems with MIRF1. They bypassed the station.

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

MI RF experts brought MIRF1 back online at 4:02 PM with a temporary repair.

At 8:32 PM, store 6619 was lost when the TeV suffered an abort; there was no quench. Operators investigated and discovered that a 13.8 kV breaker tripped off at TeV sector B2. Operators continued their investigations and called in experts.

At 10:18 PM, Operators reported that they found a bad Pbar Debuncher power supply at AP-3 (D:HT906T). They replaced the power supply with a spare.

At 11:45 PM, Operators reported that the bad spare Pbar Debuncher power supply was also bad. They replaced the supply again.

TeV experts reported at 11:47 PM that they were beginning their repairs at sector B2.

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

Saturday Dec 6

The midnight shift began with TeV experts working at sector B2, with Operations monitoring the stash (375.5E30), with Pbar stacking (62.4E10), and with MiniBooNE taking beam.

Operations put the TeV through a dry squeeze at 1:25 AM.

Operations put the TeV through a wet squeeze at 1:59 AM.

At 2:07 AM, the P1 transfer line tripped off for the first of three times in 13 minutes. It reset.

Operations put the TeV into shot setup at 2:23 AM.

At 3:24 AM, the MiniBooNE horn tripped off. It reset.

Operations established store 6622 at 3:46 AM with a corrected initial luminosity of 332.18E10. Operators reported a luminosity difference between CDF and D0. (The Run Coordinator gave Operations the corrected luminosity number.)

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

A TeV expert reported at 2:06 PM that the TeV was not causing the D0/CDF luminosity difference.

Operations terminated store 6622 at 3:33 PM.

TeV experts began a lattice study at 3:35 PM.

Operations put the TeV through a wet squeeze at 6:33 PM.

Operations put the TeV into shot setup at 6:59 PM.

Operations reported at 8:05 PM that the Recycler had stashed 11 times during the last 12 hours.

Operations established store 6625 at 9 PM with a corrected initial luminosity of 355.07E30. This set a new record luminosity. (The Run Coordinator gave Operations the corrected luminosity number.)

Sunday Dec 7

The midnight shift began with Operations monitoring store 6625 and the stash, with Pbar stacking, and with MiniBooNE taking beam.

Operations reported at 8:01 AM that the Recycler had stashed 11 times during the last 12 hours.

Operations terminated store 6625 around 9 AM.

Operations prepared CDF and D0 for an access at 9:18 AM.

Cryo system experts began work on the TeV sector A3 wet engine at 9:36 AM.

Pbar experts began a study at 2:18 PM that halted stacking.

The Pbar study ended and stacking resumed stacking at 3:56 PM.

A Pbar expert began another study at 4:15 PM.

At 4:54 PM, a TeV sector B0 quadrupole power supply tripped off on a ground fault indication. Operators investigated and called in an expert.

TeV power supply experts brought B0Q5 on at 6:28 PM.

Operations began ramping the TeV at 7:52 PM.

Operations reported at 7:54 PM that the Recycler had stashed six times during the last 12 hours.

Operations put the TeV through a dry squeeze at 8:04 PM.

Operations put the TeV through a wet squeeze at 9:23 PM.

Operations put the TeV into shot setup at 9:46 PM.

Operations established store 6628 at 11:06 PM with an initial luminosity of 338.67E30.

At 11:16 PM, the P1 transfer line tripped off. It reset.

Monday Dec 8

The midnight shift began with Operations monitoring store 6628 and the stash, with Pbar stacking, and with MiniBooNE taking beam.

Operations reported at 8:14 AM that the Recycler had stashed nine times during the last 12 hours.

The Plans for Monday

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

Accelerator Update Archive

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