Accelerator Update for March 10, 2008 - March 12, 2008

Monday March 10

The day shift began with Operations monitoring the Tevatron (TeV) store 5970 (94.51E30) and the Recycler stash (225.2E10), with the Antiproton Source stacking (39.4E10), with the Main Injector (MI), Linac, and Booster operating normally, with the Collider Detector at Fermilab (CDF) and DZero (D0) using the colliding beams, with NuMI off for dehumidifier work, and with the SciBooNE / MiniBooNE (BNB) experiments taking beam.

At 8:24 AM, the AP1 transfer line beam permit tripped off due to bad beam positions. It reset.

MI experts began a coalescing study at 9:44 AM.

A TeV expert began a 30-minute Schottky study at 10:18 AM.

At 10:46 AM, Operations reported a Pelletron front-end (FE) alarm. An expert instructed Operations to reboot the FE, but this action broke the communication link between the Pelletron and the AccelNet2. Experts investigated.

At 12:44 PM, a TeV power supply (T:SF) tripped off on an interlock fault. This caused store 5970 to abort. Operators investigated and found a passive filter that had failed and a blown disconnect fuse. Experts began their repairs.

At 12:52 PM, the AP1 transfer line tripped off due to bad beam positions. It reset. Operations reported that the HV100 magnet trips off on a high temperature indication during each AP1 trip. An expert investigated to see if HV100 was the cause of the AP1 trips.

At 1:08 PM, AP1 tripped off for the first of five times in about 90 minutes. It reset.

Operations put the TeV through a dry squeeze at 1:13 PM.

A power supply expert reported at 2:22 PM that he was working on SQD1 and SQC4 while T:SF was being repaired. He completed his work about 45 minutes later.

At 2:23 PM, a MI RF station (MIRF15) tripped off. It reset.

At 2:46 PM, RF experts replaced the chassis for MIRF11.

The MI coalescing study ended at 3:04 PM.

The Neutron Therapy Facility (NTF) reported at 3:29 PM that they had completed treatment on their last patient for the day.

A power supply expert reported at 3:52 PM that the safety system was causing HV100 to trip off.

Operations reported at 3:57 PM that the Recycler had stashed antiprotons three times during the days shift.

At 4:23 PM, the AP1 transfer line tripped off due to bad beam positions for the first of three times in about 30 minutes.

At 5:29 PM, Operations reported that beam was not making it from Pbar into MI. Experts investigated.

A power supply expert reported at 5:33 PM that he had completed his work on T:SF.

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

A MI expert tuned the MI bunch rotation at 6:23 PM. She successfully made the beam narrower.

Operations put the TeV through a wet squeeze at 6:25 PM.

Operations put the TeV into shot setup at 7:37 PM.

At 7:53 PM, the AP1 transfer line tripped off due to bad beam positions for the first of four times in an hour.

Operations established store 5974 at 9:48 PM with an initial luminosity of 278.2E30.

At 10:56 PM, operators reported that they replaced a beam monitor at AP1.

Operations reported at 11:55 PM that the Recycler had stashed three times during the evening shift.

Tuesday March 11

The midnight shift began with Operations monitoring store 5974 (181.11E30) and the stash (96.9E10), with Pbar stacking (14.5E10), with NuMI off for dehumidifier work, and with BNB taking beam.

At 12:38 AM, the AP1 transfer line tripped off due to bad beam positions for the first of two times in 14 minutes. It reset.

At 1:21 AM, the AP1 transfer line tripped off due to bad beam positions for the first of 10 times in about five hours. It reset.

At 5:54 AM, a Linac Klystron RF station (KRF6) tripped off. It reset.

At 6:04 AM, the BNB horn LCW system alarmed on a low level indication. Operations contacted experts.

Operations turned off BNB beam at 7:21 AM so that experts could work on the horn LCW system.

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

Operations reported at 9:35 AM that Preaccelerator experts were switching from the H- Source to the I- Source.

Pbar experts began a study at 9:58 AM that halted stacking.

An RF expert began work on MIRF5 at 9:59 AM. After he completes that repair, he will then work on MIRF11.

Booster experts brought an octupole magnet power supply online at 10:02 AM. (Later, the experts reported that the octupole magnet didn’t perform as was hoped.)

At 11:12 AM, a controls problem halted the Pbar core cooling studies. Operations put Pbar into stacking mode.

At 11:55 AM, the 400MeV area beam permit tripped off due to bad beam positions. It reset.

A MI expert began an IPM study at 1:08 PM. The MI study ended at 3:45 PM.

Pbar and MI experts reported at 3:46 PM that they had been investigating the cause of all the AP1 transfer line trips.

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

The BNB horn LCW work was completed and Operations prepared the area to resume taking beam at 4:34 PM.

At 4:45 PM, an expert reported that the level of LCW in the BNB horn had dropped.

Operations terminated store 5974 at 5:05 PM. Operators prepared MiniBooNE for another access. Later, experts reported that there was air trapped in the LCW system.

Operations prepared D0 for an access at 5:23 PM.

MiniBooNE came out of access and Operations prepaired the area for beam at 5:40 PM.

At 6:45 PM, Operations reported problems with the beam to BNB. Operators investigated and discovered that the Booster dampers were off. Operations contacted Booster experts.

At 7:08 PM, the I- Source tripped off. Operators investigated and found the reference voltage off. It reset.

D0 came out of access at 7:09 PM.

NuMI finished their dehumidifier work and came out of access at 7:24 PM.

At 7:36 PM, LRF2 tripped off. It reset.

Operations put the TeV through a dry squeeze at 7:47 PM.

Operations put the TeV into shot setup at 8:28 PM.

At 9:28 PM, MIRF5 tripped off. It reset.

Operations reported at 9:33 PM, that a Booster expert found the cause of the bad BNB beam; it was due to the Booster radial offset curve getting its settings from a bad table. Normal beam to BNB resumed.

Operations established store 5977 at 10:32 PM with an initial luminosity of 247.4E30.

At 10:33 PM, BRF16 tripped off. It reset.

Operations established beam to NuMI at 11:42 PM.

Operations reported at 11:57 PM that the Recycler had stashed four times during the evening shift.

Wednesday March 12

The midnight shift began with Operations monitoring store 5977 (180.19E30) and the stash (64.0E10), with Pbar stacking (22.4E10), and with NuMI and BNB taking beam.

At 12:56 AM, BRF16 tripped off for the first of three times in one hour. It reset.

At 1:23 AM, KRF2 tripped off. It reset.

At 2:29 AM, LRF4 tripped off. It reset.

At 5:11 AM, the NuMI beam permit tripped off due to a current drop on a power supply (V108). It reset.

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

The Plans for Wednesday

The plans for today are to stack, stash, and store. Experts are investigating a possible MI LCW leak. NuMI reports that they will need an eight-hour access to blow out some clogged drain lines. The Run Coordinator may schedule this access, and possibly some other work, for this afternoon.

Accelerator Update Archive

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