Minutes of the Oct 15, 2010 Tevatron Dept Meeting

http://indico.fnal.gov/conferenceDisplay.py?confId=3669

* News (Ron) - Alex Valishev has transferred to the APC, but he will continue
to support Tevatron operations as part of his duties.

* Weekly Operations Summary (Xiaolong Zhang) - The Tevatron delivered 44 pb^-1
to CDF and D0 to the experiments over the past 7 days.  There have been 9 HEP 
stores with initial luminosities between 157 and 337 ub^-1/s.  Store 8172
aborted after only 1 hr from a fault with the E3 electrical dump.  Two other
stores were lost during shot-setup: shot 8159 quenched in the squeeze when
a low-beta trim quad supply could not slew fast enough for a newly added alpha
bump at D0 and caused high losses (was not a problem for check-out with a 
proton-only store); shot 8166 quenched during the b2 unwind early in ramp due
to a single corrupted slot in a sextupole current card.  We need to attack a 
couple of problems: decreasing pbar lifetime later in stores which has reduced
integrated luminosity, and occasional spikes observed in the Schottky power
apparently caused by something kicking or putting noise on the beam(s).
Instrumentation experts continue debugging the D1 BPM problems.

* Longitudinal Distribution Study (C-Y Tan) - In this latest iteration shaking
the RF phase to change the longitudinal distributions of proton bunces, Tan
used beam with 5-bunch coalescing to obtain smaller initial emittances.  He
also tried shaking in 1-second intervals instead of single, longer shake.
There is always some beam loss regardless of the shaking scheme.
Bunch-to-bunch differences can cause some bunches to continue "dancing" while
others become stable.  He will examine pbars which should be dancing more
strongly at 150 GeV due to their small longitudinal emittance.

* TEL-2 Hollow e-beam Studies (Giulio Stancari) - Giulio and Alex conducted
their first beam studies with the new hollow e-beam gun in TEL-2.  After
aligning the e-beam on pbar bunches, they varied the e-beam hole size to
demonstrate how the loss rate changes.  With a small electron hole, the
observing scraping was mainly longitudinal (off-momentum particles were 
removed).  They demonstrated TEL-2 can be run with little impact on the 
bunches being acted upon.  They will repair the measurements with TEL-1 on (to
clean the abort gap) so they can do their TEL-2 studies parasitically during
HEP stores.

* Plans for Next Week (All)

   - Deliver luminosity.
   - Investigate decreasing pbar lifetime and occasional Schottky noise spikes.
   - D1 BPM investigation and tests (Instrumentation)
   - T-980 Crystal Collimator (Dean et al., end-of-store)
   - TEL-2 (Alex and Giulio, end-of-store)