Minutes of the 23 April 2010 Tevatron Dept Meeting

http://indico.fnal.gov/conferenceDisplay.py?confId=3310

* News (Ron) - The new effort-reporting system will go live the week of June 7;
expect some training in mid-May.

* Weekly Operations Summary (Xiaolong Zhang) - The Tevatron delivered
53.3 pb^-1 to the experiements over the past 7 days.  There have been 7 stores
with initial luminosities between 266 and *ANOTHER NEW RECORD* 402 ub^-1/s!
Only store 7748 was lost uninentionally (after 38 hours) when an incorrect 
access key was turned and dropped the Tevatron electrical safety interlock.
Minor tuning was done to reduce proton halo at the start of HEP.  As a test,
the (proton) longitudinal damper gain was reduced at the onset of a pbar
longitudinal instability; whether that helped the pbars was inconclusive, but
the protons blew-up a few minutes later, so it's clear we need the higher gain
for the protons.  Various items fixed: synchtron light monitor readings, BLMs
in B1 (loose HV connector), 1.7 GHz Schottky proton horz channel, crystal
collimator/IPM front-end code, turbopump maintenance in A3.  The D4 house
requiring a cryogenic deriming (several hours) following a problem during wet 
engine maintenance.  We discovered the PBJ antiproton noise sournce has been 
in a low-power mode for an unknown amount of time; that may have contributed 
to the higher peak luminosities and we will disable it completely since losses
through the squeeze have been acceptable.

* Recent Crystal Collimation Results (Dean Still) - There has been effort to
improve the simulation and account for observations seen in the vertical
multi-strip volume reflection studies.  Incorporating particle loss in the
amorphous silicon part of the strips does help reproduce some structure in the
loss pattern downstream of the crystal.  Other items to address in simulation:
crystal imperfections/skewness, using recent lattice, effect of DC beam in/out
of time with bunches, physical apertures in machine.

* Plan for Next Week (All)

   - Deliver luminosity!
   - Crystal Collimator (Dean et al., end-of-store)
   - Pbar-only store? (verify BPM TBT timing, coupling on ramp, lattice 
                       measurements)
   - 150 GeV Chromaticity Study (Tan, proton-only)
   - B0/D0 Aperture Scans (Bruce, Alex, proton-only)