Accelerator Update - August 4-August 6

The integrated luminosity for last week was 6.0 pb^-1.

Monday August 4
The day shift began with the Antiproton Source (Pbar) stacking, and with the Tevatron (TeV) being put through a dry squeeze.

Switchyard experts established 120 GeV protons to the MTest experiment in the Meson beam line.

Operations put the TeV into shot setup at 9:04 AM.

Two Booster RF station (BRF5 & 6) tripped off due to high vacuum pressure. They reset okay.

Operations established store 2859 at 11:41 AM with an initial luminosity of 4.1E31. Pbar resumed stacking.

MiniBooNE technicians accessed their tunnel at 12:15 PM.

A Booster expert began work on a power supply (ORBMP) at 12:41 PM. He found a small internal LCW leak. This halted stacking. He had the supply back in operation by 1:37 PM.

At 1:57 PM, the Main Injector (MI) suffered a vacuum pump trip and valve closure.

A MI expert began a slipstacking study at 3 PM. She finished her study at 4:34 PM.

Stacking stopped at 8:21 PM. Operators investigated and discovered a bad Pbar crate power supply. They changed the power supply and stacking resumed at 9:13 PM.

At 8:31 PM, at Linac RF station (LRF2) tripped off. It reset okay, but operators reported hearing a loud humming noise. A Linac expert suggested a fix when an appropriate moment occurred.

Tuesday August 5
The midnight shift began with Operations monitoring store 2859, with Pbar stacking, and with MiniBooNE taking beam.

TeV experts began an end-of-store study at 7:29 AM.

Operations terminated store 2859 at 7:35 AM.

At 8:31 AM, Fermilab experienced a network problem. The Feynman Computing Center lost its power. This problem was resolved later in the morning.

Operators prepared MiniBooNE for access at 9 AM.

While trying to set up a TeV 36x4 study-store, the TeV aborted due to a sector A4 quench. A quadrupole magnet (A4Q9) quenched. Experts replaced a quench card and installed a recorder to monitor the power supply.

At 1:13 PM, operators discovered at TeV quadrupole power supply (C:BQ0) with no output current. Earlier this morning operators noted this supply's odd behavior. Experts were called to investigate.

Pbar resumed stacking at 2 PM.

Operations put the TeV through a dry squeeze at 2:04 PM.

TeV power supply experts began replacing C:BQ0's reversing switch at 2:11 PM. They completed their work at 3:41 PM.

Operators prepared the Collider Detector Facility (CDF) for access 2:47 PM. The experimenters came out of access fifty minutes later.

Operations established beam to MiniBooNE at 3:29 PM.

Operations put the TeV through a dry squeeze at 4:37 PM and then at 6:44 PM established a 36x4 study-store.

At 6:45 PM, the TeV suffered a sector A4 quench.

A Booster RF station (BRF12) tripped off at 6:52 PM for the first of three times over an hour. It reset okay each time.

At 8:06 PM, the TeV sector A0 cryo compressor tripped off due to a loss of power, as did several others around the ring. The Duty Electrician reset the tripped breaker, which initially caused the problem. He could not find a cause for the trip.

Operator found the QPMs for TeV sector F3 & 4 not responding. They reloaded data. Operators believed that this was also due to the power outage.

Pbar resumed stacking at 10:16 PM.

Operations put the TeV through a dry squeeze at 11:47 PM.

Wednesday August 6
The midnight shift began with Pbar stacking, with MiniBooNE taking beam, and with Operations putting the TeV through a squeeze.

Operations put the TeV into shot setup at 1:24 AM. At 4:27 AM, Operations established store 2864 with an initial luminosity of 3.6E31. Pbar resumed stacking.

Operators tuned the Booster beam at 5:28 AM.

Today's Plan
The plan for today is to stack and store. Accelerator Update Archive

More Information
For Tevatron luminosity charts and the current status of Fermilab's accelerators and detectors (live!), please go to Fermilab Now

Comments and Suggestions
What do you think about the Accelerator Updates? Please send comments and suggestions to: accelupdates@fnal.gov.