Accelerator Update for September 22, 2008 - September 24, 2008

Monday Sept 22

The day shift began with the Tevatron (TeV) in shot setup, with Operations monitoring the Recycler stash (394.1E10), with the Antiproton Source (Pbar) stacking (94.5E10), with the Linac, Booster, and the Main Injector (MI) operating normally, with the MiniBooNE and NuMI experiments taking beam, with the Meson MTest experiment off during shot setup, and with the Collider Detector at Fermilab (CDF) and DZero (D0) waiting for the next store.

Operations established store 6434 at 9:12 AM with an initial luminosity of 293.97E30.

Operations established beam to MTest at 9:26 AM.

A Booster expert began tuning the Booster at 9:42 AM to get better beam to MiniBooNE.

A MI expert began a 12- batch slipstacking study at 10:39 AM.

At 10:44 AM, the MiniBooNE beam permit tripped off for the first of seven times in 2.5 hours due to bad beam positions.

A controls expert reported at 11:21 AM that he had replaced the MADC power supply for a Switchyard (SY) crate ($80).

At 2:31 PM, a Booster vacuum pump tripped off. An expert investigated.

At 2:40 PM, a Linac RF station (LRF1) tripped its breaker. An expert reset it.

A Pbar expert reported that they had re-enabled the SEM software drivers for crate #11 at 3:21 PM.

At 3:31 PM, Operations reported that the gradient for LRF4 was fluctuating. Linac experts investigated.

At 3:50 PM, Operations reported that the voltage for a Pbar Debuncher RF station (DRF1-5) decreased by a considerable amount. Operations contacted an expert.

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

At 4:27 PM, DRF1-7 tripped off. An expert investigated.

At 4:51 PM, a TeV vacuum trip caused the Tevatron Electron Lens (TEL) to trip off momentarily.

At 5:56 PM, an Accumulator RF station (ARF1) had its readback come into alarm on a high temperature indication. Operators opened the door to the station’s relay racks and positioned a fan. The temperature came down.

Operations disabled the MTest beam at 6:23 PM.

At 6:44 PM, Operations reported that ARF1 was pulsing only half of the time due to temperature problems. Operations contacted the Duty Mechanic who reported that the AC for AP-50 had tripped off. He brought it back on and with the help of an expert, operators managed to get ARF1 back to normal operations.

At 7:01 PM, Operations reported problems getting beam to NuMI. Operators investigated. A MI expert was called in.

Operations reported at 7:48 PM that even though the ARF1 profile looked better, too much beam was being left in the injection orbit. Operations contacted an expert.

Operators reported at 8:16 PM that they closed the door to the ARF1 relay racks and the station resumed normal operations. However, the temperature alarm returned.

At 9:27 PM, LRF1 tripped off. It reset.

An MI expert reported at 9:48 PM that he had found and fixed some wrong bucket parameters. NuMI resumed getting normal beam.

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

Tuesday Sept 23

The midnight shift began with Operations monitoring the store 6434 and stash (392.0E10), with the Pbar stacking (19.2E10), and with the MiniBooNE and NuMI experiments taking beam.

Operations terminated store 6434 at 12:46 AM.

Operations put the TeV into shot setup at 12:58 AM.

At 2:14 AM, the TeV suffered a quench at sectors B1, BC, and BD. Sectors BA and BB then quenched on a lead failure. The first quench occurred on step 17 of the low beta squeeze.

Operations reported at 3:28 AM that they discovered a bump that TeV experts had added just before this store. Operations talked with TeV experts and they confirmed that the quench was caused by the bump. Operators took the bump out of the sequence.

Operations established beam to MTest at 4:42 AM.

Operations put the TeV through a dry squeeze at 5:37 AM.

At 5:37 AM, BRF11 tripped off. It reset.

Operations put the TeV through the first of three wet squeezes at 6:20 AM.

Operations reported at 8:05 AM that the Recycler had stashed four times during the midnight shift.

At 8:19 AM, the MIRF watchdog tripped off on an “overdrive” indication. It reset.

A TeV expert began a chromaticity tracker study at 8:28 AM.

At 8:56 AM, the TeV aborted due to a sector F4 BLM. The abort reset and Operations injected more beam into the TeV.

At 9:24 AM, LRF4 tripped off. It reset.

At 10:02 AM, LFR4 tripped off for the first of two times in 18 minutes. Experts investigated.

Linac experts reported at 10:50 AM that they found and fixed an open circuit in LRF4.

At 12:35 PM, KRF6 tripped off and would not reset. Experts investigated. They had the station back online about 30 minutes later.

At 12:37 PM, Operations reported that the TeV sector E4 wet engine needed a bearing cap replacement. Cryo system experts completed the job in about 20 minutes.

The Neutron Therapy Facility reported at 1:19 PM that they had treated their last patient for the day.

MTA - MuCool came out of access at 2:11 PM.

A TeV RF expert reported at 3:06 PM that he had replaced the metering chassis for TRF4.

At 3:10 PM, KRF6 tripped off. It reset.

At 3:35 PM, the NuMI beam permit tripped off due to beam in the kicker gap for the first of three times in 37 minutes. A MI expert investigated.

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

At 4:25 PM, the 400MeV area beam permit tripped off due to bad beam positions. It reset.

TeV experts completed their studies at 6:11 PM.

Operations disabled the MTest beam at 6:24 PM.

Operations put the TeV into shot setup at 6:32 PM.

At 6:59 PM, the MIRF stations watchdog tripped off for the first of three times in one hour. It reset.

Operations established store 6442 at 8:15 PM with an initial luminosity of 267.74E30.

At 8:59 PM, the MiniBooNE horn tripped off on a ground fault indication. It reset.

At 9:09 PM, Operations reported that the antiproton production had slowed for a few minutes and then returned to normal with no indication of a problem.

At 10:08 PM, the MIRF stations watchdog tripped off. Operations noted that MIRF15 had been acting oddly. Operators bypassed the station.

At 10:51 PM, KRF1 tripped off for the first of many times over 10 minutes. Operators adjusted the switch balance.

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

Wednesday Sept 24

The midnight shift began with Operations monitoring store 6442 (144.4E30) and the stash (125.6E10), with Pbar stacking (36.0E10), and with the MiniBooNE and NuMI experiments taking beam.

At 1:06 AM, the MI Power Supply interlock Loop tripped off. Operators conferred with experts and then an expert was called in.

Operations put Pbar into standby mode at 1:14 AM.

A power supply expert reported at 3:10 AM that he found a failed control power supply in the MI-40 upper power supply. This supply was offline and not being used. MI resumed sending beam to Pbar and NuMI at 3:19 AM.

At 3:21 AM, Operations reported more MIRF watchdog trips. Operations lowered the beam intensity.

At 3:40 AM, LRF4 tripped off. It reset.

Operations established beam to MTest at 4:12 AM.

At 4:48 AM, LRF4 tripped off. It reset.

At 6:01 AM, a Booster vacuum pump (IPRF17) tripped off and caused BRF7 and 8 to also trip. Everything reset.

Operations reported at 7:59 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.

Accelerator Update Archive

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