Accelerator Update for April 30, 2008 - May 2, 2008

Wednesday April 30

The day shift began with Operations monitoring the Recycler stash (239.9E10), with the Antiproton Source (Pbar) stacking (30.2E10), with the Main Injector, Booster and Linac operating normally, with the Collider Detector at Fermilab (CDF) and DZero (D0) in access, and with the NuMI and SciBooNE / MiniBooNE (BNB) experiments taking beam.

At 8:30 AM, a Linac Klystron RF station (KRF6) tripped off. It reset.

Operations began preparing the Tevatron (TeV) F- sector for access at 8:37 AM.

Operations put Pbar in standby at 8:38 AM due to the F-sector access.

Operations reported at 8:45 AM that technicians would be working on the MINOS sump pumps and there might be some alarms.

Operations had the TeV A-E sectors prepared for access by 9:38 AM.

Operations prepared the TeV transfer hall for access at 9:43 AM.

Cryo system experts began warming up the TeV sector A4 cryo system at 9:45 AM to work on a Kautzky valve.

Operations reported at 9:59 AM that operators had the Pbar PreVault and Pretarget prepared for access.

CUB reported at 10:10 AM that they were switching the Linac LCW pumps.

Operations reported at 10:12 AM that operators had prepared the NuMI absorber and alcoves for access.

A LCW expert reported at 10:47 AM that pump #4 had faulted off twice due to its driver. He switched Linac back to its original pump configuration, using pump #5.

Power supply experts reported at 11:20 AM that they had inspected a TeV quadrupole power supply (DQ0) and had found a loose connection that was causing the unexplained polarity changes.

A RF expert reported at 11:28 AM that he was working on a Pbar Accumulator RF station (ARF4).

Booster experts reported at 11:46 AM that they were working on a Booster kicker (MP03).

Instrumentation experts reported at 11:59 AM that they were calibrating the TeV DCCT.

The TeV F-sector access ended at noon.

Operations established beam to BNB at 12:21 PM.

Operations established beam to Switchyard (SY) and the MTest experiment at 12:50 PM.

At 1:09 PM, the Linac Klystron Vernier tripped off. It reset.

Operations began sending beam to Pbar for stacking at 1:50 PM.

At 2:14 PM, BRF11 tripped off. It reset.

NuMI came out of access. Operations established beam to NuMI at 2:19 PM.

Water experts reported at 2:51 PM that the TeV sector A4 air compressor was failing. They valved in the backup compressor.

Cryo system experts reported at 3:22 PM that they had completed their work on the TeV sector A4 cryo system and were beginning its cool down.

The TeV A-E sectors came out of access at 3:25 PM.

CDF experimenters informed Operations at 3:27 PM that they had closed up the detector’s west plug.

At 3:33 PM, KRF7 tripped off. It reset.

At 3:52 PM, the NuMI beam permit tripped off. It reset.

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

At 4:06 PM, KRF7 tripped off. It reset.

At 4:45 PM, KRF3 and KRF4 tripped off. They reset.

Operations prepared the TeV A-E sectors at 5:41 PM for an access by interlock experts.

At 6:01 PM, KRF6 tripped off. It reset.

A MI expert finished a study at 6:13 PM.

At 6:21 PM, BRF11 tripped off. It reset.

Interlock experts reported at 6:55 PM that they found and repaired a bad emergency exit switch at TeV sector A3.

Operators completed searching and securing the CDF collision hall at 7:22 PM.

D0 came out of access at 7:35 PM.

Operations began the TeV turn on at 7:36 PM.

Operations disabled beam to MTest at 8:15 PM.

At 9:28 PM, KRF7 tripped off. It reset.

At 9:30 PM, KRF4 tripped off. It reset.

Operations put the TeV through a dry squeeze at 9:46 PM.

At 10:07 PM, KRF6 tripped off. It reset.

Operations put the TeV through a wet squeeze around 10:45 PM.

Operations put the TeV into shot setup at 11:05 PM.

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

Thursday May 1

The midnight shift began with the TeV in shot setup, with Operations monitoring the stash (323.5E10), with Pbar stacking (133.5E10), and with NuMI and BNB taking beam.

At 12:43 AM, KRF3 tripped off. It reset.

At 12:58 AM, Operations reported that a TeV antiproton abort kicker (C:AAK1) had faulted. Operators investigated and found the kicker’s filament power supply was off. Operators contacted an expert who had them turn the power supply on and began the timing in process.

At 1:02 AM, KRF6 tripped off. It reset.

Operations established store 6102 at 1:12 AM with an initial luminosity of 234.9E30.

TeV experts warned at 2:03 AM that C:AAK1 would probably prefire and cause a quench. Operations warned CDF of this possibility and they turned off their Silicon detector. C:AAK1 power supply had timed in after about 15 minutes and charged to 36kV.

At 2:08 AM, KRF7 tripped off. It reset.

At 2:28 AM, KRF6 tripped off. It reset.

At 5:25 AM, KRF4 tripped off. It reset.

At 5:47 AM, BRF13 & 14 tripped off due to a Booster vacuum pump (IPRF23) tripping off. Everything reset.

At 5:50 AM, KRF3 tripped off. It reset.

At 5:54 AM, BRF13 & 14 again tripped off due to IPRF23. Everything reset.

Operations established beam to MTest at 6:39 AM.

At 6:41 AM, KRF4 tripped off. It reset.

At 7:44 AM, KRF2 tripped off. It reset.

Operations reported at 7:55 AM that the Recycler had stashed five times during the midnight shift.

At 8:53 AM, KRF7 tripped off. It reset.

At 11:39 AM, KRF7 tripped off two times in about 90 minutes. It reset.

At 12:03 PM, KRF4 tripped off. It reset.

At 12:19 PM, KRF6 tripped off. It reset.

At 12:37 PM, BRF9 tripped off. It reset.

At 1:18 PM, KRF3 tripped off. It reset.

Cryo system experts reported at 1:20 PM that they had completed their repairs on the TeV sector A DEWAR.

At 1:42 PM, Operations reported that about 50E10 of antiprotons were lost from the stash. Later, Recycler experts reported that the loss was due to a temperature problem with the new dampers.

At 2:15 PM, BRF9 tripped off. It reset.

Operations terminated store 6102 at 2:30 PM. A TeV kicker expert began his C:AKK1 repair.

Operations prepared CDF for access at 2:44 PM.

At 3:25 PM, the NuMI beam permit tripped off due to a power supply’s (E:V108) low output current. It reset.

Recycler experts reported at 3:36 PM that they were switching back to the old damper.

A MI expert began a coalescing study at 3:58 PM.

At 3:59 PM, KRF6 tripped off. It reset.

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

CDF came out of access at 4:41 PM.

The expert working on the AAK1 kicker reported at 4:47 PM that he had replaced its breaker and had conditioned all the TeV sector A0 kickers.

At 5:29 PM, KRF4 tripped off. It reset.

Operations put the TeV through a dry squeeze at 5:50 PM.

At 5:53 PM, the TeV sector A1 air compressor tripped off. Operators investigated and unstuck the valve that opens automatically to drain water out of the tank.

Operations halted the MTest beam for the night at 6:06 PM.

Operations put the TeV into shot setup at 6:20 PM.

At 7:26 PM, KRF2 tripped off. It reset.

At 7:31 PM, just as the next store was about to be established, the TeV suffered a quench at sectors B0 and F4 during the squeeze. Operators investigated and informed TeV experts.

At 9:18 PM, LRF3 tripped off. It reset.

At 9:34 PM, KRF7 tripped off. It reset.

Operations put the TeV through its first ramp at 10:45 PM.

Operations put the TeV through the first of three dry squeezes at 11:04 PM.

At 11:15 PM, MIRF6 tripped off. It would not reset. Operators investigated and then bypassed the station. Operations had to lower the intensity of the beam to NuMI due to the RF reconfiguration.

At 11:29 PM, KRF7 tripped off. It reset.

Operations put the TeV through the second of three dry squeezes at 11:58 PM.

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

Friday May 2

The midnight shift began with the TeV in a dry squeeze, with Operations monitoring the stash (121.8E10), with Pbar stacking (33.8E10), and with NuMI and BNB taking beam.

At 12:22 AM, Operations reported that the Pelletron VME was not responding. Operations called in an expert.

At 12:46 AM, BRF4 tripped off. It reset.

Operations put the TeV through its third dry squeeze at 12:48 AM.

At 1:34 AM, the Linac Klystron Debuncher went 180 degrees out of phase. Operators brought the station back within its tolerances.

Operations put the TeV through a wet squeeze at 2:31 AM.

Around 2:45 AM, KRF3 tripped off. It reset.

A Recycler expert reported at 2:46 AM that he was able to reset the front end. Operations turned the Pelletron back on.

Operations put the TeV into shot setup at 4:43 AM.

Operations established store 6109 at 6:39 AM with an initial luminosity of 176.16E30.

At 7 AM, BRF6 tripped off. It reset.

At 7:14 AM, KRF4 tripped off. It reset.

Operations established beam to MTest at 7:35 AM.

Operations reported at 7:59 AM that the Recycler had stashed three times during the midnight shift.

The Plans for Friday and the Weekend

The plans for today are to return to stable stacking, stashing, and storing. The Run Coordinator will allow TeV experts to conduct orbit studies, for MI an expert to conduct coalescing studies, and for Linac experts to conduct an LRF4 study.

Accelerator Update Archive

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