Minutes of the Oct 3, 2008 Tevatron Dept Meeting

http://indico.fnal.gov/conferenceDisplay.py?confId=2151

* News (Ron) - The Tevatron ended the FY08 running with nearly
1800 pb^-1 delivered to CDF and D0, nearly 500 pb^-1 more than the 
previous best.  The Accelerator Division had a very safe FY08: 
there were no recordable injuries or days away/restricted duty.  
There will be (nearly) site-wide power outages next week on Monday 
and Friday from 07:00 to about 07:30.  Booster Tower West will 
have no power all day on Tuesday.  Plan accordingly.

* Weekly Operations Summary (Bruce Hanna) - The Tevatron delivered 
over 47 pb^-1 to the experiments this week.  There have been 10 
stores with initial luminosities between 184 and 274 ub^1/s. Store 
6460 was lost prematurely when a breaker in the B4 house tripped 
and cut power to all the electronics; nothing was found wrong with 
the breaker.  One shot was lost as collisions were initiated - 
high proton losses arising from beam-beam effects were the cause.  
We have been fighting high losses at CDF due to the apparent 
aperture restriction there - pbar intensities have been kept lower 
intentionally as we attempt to diagnose.  (See more below.)  The 
Recycler's Electron Cooling failed on Thursday resulting in lower 
pbar intensities and larger emittances. Multi-bunch proton 
injection was used successfully for store 6469. Other problems 
include: E1 and F1 wet engines tripping off during HEP, D17-3 
collimator not moving, continued timeouts when trying to make 
setting to dipole corrector, spurious B48 separator sparks.

* CDF Aperture Scan Results - Scans at 150 GeV using new bumps 
developed by Alex Valishev indicate an aperture restriction 
consistent with the B-side corrugated beampipe, not something 
dangling in the pipe as previously thought.  The restriction 
located fairly well to ~1.7 upstream of the B0DN BPM - near the 
interface between the rigid and corrugated sections of (warm) 
beampipe.  It looks as though the pipe is low and to the radial 
inside.  We will try to adjust the pipe during next week's shutdown.

* Shutdown Planning - Jim Volk reviewed the jobs currently in the 
worklist.  Most jobs are simple, minor maintenance in the cryo, 
electrical and mechanical systems.  A priority is a survey and 
adjustment of the B-side CDF beampipe.  Another priority is to 
hunt for the ground fault in F4.  We will also try to make roll 
measurements of all the magnets using Jim's digital protractors. 
The shutdown will likely start 1 day early on Sunday since 
Recycler electron cooling is broken.  We expect the Tevatron to be 
ready for start-up on Saturday.