Accelerator Update for April 25, 2008 - April 28, 2008

Friday April 25

The day shift began with the Tevatron (TeV) in shot setup, with the Antiproton Source (Pbar) stacking (89.0E10), with the Recycler, the Main Injector, the Booster and Linac operating normally, with the Collider Detector at Fermilab (CDF) and DZero (D0) waiting for the colliding beam, and with the NuMI and SciBooNE / MiniBooNE (BNB) experiments taking beam.

Operations established store 6082 at 8:31 AM with an initial luminosity of 213.2E30.

A power supply expert reported at 8:26 AM that he was going to be working on a MI power supply (M:HV102) for about 30 minutes.

At 8:39 AM, a Linac Klystron RF station (KRF6) tripped off. It reset.

At 10:15 AM, Operations reported that a MI Lambertson (LAM10) tripped off. Experts investigated and reported that its safety system permit was missing. This Lambertson gets its permit from the Booster safety system. Interlock experts investigated and fixed the problem.

A RF expert began fixing the LCW leak on MIRF10 at 10:17 AM. He completed the repair about 40 minutes later.

Operations put Pbar into standby at 10:24 AM.

At 11:12 AM, Operations reported that experts had to open a MI power supply (HV860) to investigate LAM10 problem. The power supply is a critical device for BNB. Operators turned off BNB.

Pbar resumed stacking at 12:20 PM.

At 1:21 PM, LRF4 tripped off. It reset.

At 1:23 PM, BRF4 tripped off. It reset.

Operations reported at 1:47 PM that the Pbar stashing efficiency problem was caused by a MI power supply (M:HV102); it had two bad SCRs. Everything operated normally after the power supply repair.

Operations reported at 1:55 PM that a blown fuse in the LAM10 480-Volt safety system was the cause of the trip. A power supply expert reported that the he had replace fuse the and the contactor coil it was in series with.

At 2:29 PM, KRF3 tripped off. It reset.

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

At 4:17 PM, KRF7 tripped off for the first of two times in about two hours. It reset.

At 6:18 PM, the MiniBooNE dewatering system came into alarm. Operators investigated and reported that its water sensor (W3LVL) was indicating a fault. Operations contacted an expert.

At 7:44 PM, a Booster vacuum pump (B:IPRF17) tripped off and caused BRF7 & 8 to trip off. Everything reset.

At 8:01 PM, KRF7 tripped off. It reset.

At 10:11 PM, Operations reported that a TeV sector B17 vacuum pump was failing. Operations contacted an expert.

At 10:35 PM, BRF13 tripped off. It reset.

At 11:40 PM, KRF7 tripped off. It reset.

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

Saturday April 26

The midnight shift began with Operations monitoring store 6082 (51.71E30) and the stash (315.7E10), with the Pbar stacking (14.5E10), and with BNB taking beam.

Operations terminated store 6082 at 1:08 AM.

Operations put the TeV into shot setup at 1:19 AM.

At 1:36 AM, KRF6 tripped off. It reset.

At 3:06 AM, three minutes after the TeV reached flattop, the TeV quenched. Operators investigated and found that the TeV sector B2 door interlock had dropped, which caused a seven-house quench.

At 3:32 AM, a burned electronics odor was reported around a TeV quadrupole power supply (D0Q6).

At 3:33 AM, the cryo system experts at CHL reported that the system was losing helium. Operators investigated. CHL reported at 3:54 AM that the helium loss had stopped.

A vacuum expert reported at 4:14 AM that the TeV vacuum looked good.

Operations reported at 4:31 AM that an interlock expert was coming in.

Operations reported at 5:29 AM that they had prepared the TeV for an access.

Vacuum experts reported at 6:13 AM that they would come in to change vacuum turbo stations at TeV sectors B17 and E24.

Interlock experts reported at 6:34 AM that there was a little “play” in the door at TeV sector B2. It was probably a wind gust that moved the door enough to drop its interlock. The experts adjusted the door switch to allow a bit of door movement.

Two power supply experts arrived at 6:35 AM to check out the TeV sector D0 low beta magnet power supplies.

Operators completed their search and secure of TeV sector B at 6:40 AM.

At 7:06 AM, two power supply experts reported that D0Q6 had a bad contactor. They began their repairs.

A TeV expert reported at 7:36 AM that the CDF collision hall temperatures had been dropping since the experiment’s last access and would have probably caused a quench had not the TeV already quenched. Operations informed the CDF Building Manager of the temperature problem.

Operations reported at 7:58 AM that the Recycler had stashed three times during the midnight shift.

At 8:05 AM, KRF4 tripped off. It reset.

Power supply experts reported at 8:44 AM that they had completed their repairs on D0Q6.

At 8:49 AM, KRF3 tripped off. It reset.

The TeV access ended at 8:52 AM.

D0 came out of access at 8:54 AM.

At 9:28 AM, KRF6 tripped off. It reset.

At 9:35 AM, the Pelletron tripped off. It reset.

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

At 11:22 AM, MIRF6 tripped off. It took multiple resets and lowering the beam intensity to NuMI to get the station back on.

At 11:48 AM, BRF4 tripped off. It reset.

At 12:48 PM, the 400 MeV area beam permit tripped off due a bad beam position. It reset.

At 1 PM, KRF 2 tripped off. It reset.

At 1:04 PM, KRF3 tripped off. It reset.

Operations put the TeV through a wet squeeze at 1:11 PM.

At 2:18 PM, a Booster vacuum pump (B:IPBD2) tripped off. It reset.

At 2:46 PM, KRF7 tripped off. It reset.

At 3:14 PM, a vacuum pump for LRF3 tripped off. It reset.

At 3:48 PM, Operations reported that a TeV power supply (VA49) had tripped off during the TeV wet squeeze. Operators investigated and found that during the last orbit smooth, the power supply had been pushed beyond its limits. This was fixed.

At 4:10 PM, KRF6 tripped off. It reset.

Operations put the TeV into shot setup at 4:38 PM.

At 5:21 PM, Operations reported that a power supply (VTF11) was causing the P2 transfer line beam permit to trip off. Operations restarted the Pbar auto oscillation program with settings from late on the midnight shift, and this fixed the VTF11 problems.

Operations established store 6090 at 6:19 PM with an initial luminosity of 165.67E30.

Operations reported at 7:57 PM that the Recycler had stashed three times during the last 12 hours.

At 8:42 PM, KRF7 tripped off for the first of two times in about three hours. It reset.

At 9:13 PM, KRF3 tripped off. It reset.

At 9:54 PM, MIRF18 tripped off and caused NuMI to trip. Everything reset.

Sunday April 27

The midnight shift began with Operations monitoring store 6090 and the stash, with Pbar stacking, and with NuMI and BNB taking beam.

At 12:51 AM, KRF3 tripped off. It reset.

At 1:33 AM, KRF7 tripped off. It reset.

At 1:55 AM, a Booster vacuum pump tripped off and caused BRF13 and 14 to trip. Everything reset.

At 1:56 AM, MIRF7 tripped off. It reset.

At 1:58 AM, KRF6 tripped off for the first of three times in a little more that two hours on a LCW flow fault. It reset.

Operations reported at 7:55 AM that the Recycler had stashed four times during the last 12 hours.

Operations terminated store 6090 at 8:17 AM.

A TeV expert began an orbit smooth at 8:33 AM.

At 8:57 AM, KRF7 tripped off for the first of four times over the next nine hours. It reset.

Operations put the TeV into shot setup at 10:40 AM.

At noon, KRF3 tripped off. It reset.

Operations established store 6093 at 12:33 PM with an initial luminosity of 199.53E30.

At 3:42 PM, KRF4 tripped off. It reset.

At 5:43 PM, LRF4 tripped off. It reset.

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

At 9:21 PM, KRF6 tripped off. Operators had to bring the station up slowly over 28 minutes before it would operate normally.

At 9:54 PM, KRF6 tripped off. It reset.

At 10:37 PM, BRF8 tripped off. It reset.

At 11:07 PM, a Booster kicker (MP03I) tripped off. It reset.

Monday April 28

The midnight shift began with Operations monitoring store 6093 and the stash, with Pbar stacking, and with NuMI and BNB taking beam.

At 12:05 AM, KRF2 tripped off on a transformer LCW flow fault.

At 12:58 AM, KRF7 tripped off for the first of three times in about an hour. It reset.

At 1:25 AM, LRF3 tripped off. It reset.

At 1:51 AM, KRF4 tripped off. It reset.

At 4:14 AM, MP03I tripped off. It reset.

At 4:55 AM, a Booster vacuum pump (IPRF23) tripped off and caused BRF13 & 14 to trip off. Everything reset.

Operations terminated store 6093 at 5:30 AM.

Operations prepared CDF for an access at 6:02 AM.

At 6:30 AM, KRF2 tripped off. It reset.

Operations reported at 7:56 AM that the Recycler had stashed once 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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