Minutes of the Feb 1, 2008 Tevatron Dept Meeting

http://indico.fnal.gov/conferenceDisplay.py?confId=1549

* News (Ron) - The Tevatron "vacation" calendar is now available at
http://www-bd.fnal.gov/servlets/webcal?project=tevatron
(on-site only).  In addition to using it to indicate vacation days, you can 
see when Tevatron folks are taking their furlough days/weeks.

* Weekly Operations Summary (Bruce Hanna) - The Tevatron delivered 34.4 pb^-1
(average) to CDF and D0 this week.  The January monthly delivered total of
164.9 pb^-1 is the second highest ever.  There were 6 stores with initial
luminosities between 130 and 266 ub^-1/s.  A 7th store was lost just as
HEP was declared when the HA24 corrector tripped and caused a quench; a failed
cable splice was found and repaired.  The lower peak luminosities were caused
by fewer available pbars - the Recycler lost one nice stash and then there
was a long MI access to replace a quadrupole magnet.  Shot 5872 was ended
by a ground fault on the D0Q6 circuit; after much investigation, it was
found that the LCW supply for the C46 and C47 spool power leads was valved
out and caused stagnant water to plate crud onto the ceramics.  Our "PBJ" was
used successfully to blow-up pbar emittances before the squeeze of store 5874;
some more work needs to be done before using it routinely.  Low-beta lattice
measurements were also performed.  The BPMs have been mysteriously getting
into the wrong DAQ mode and causing problems with our in-store orbit 
stabilization and drifting orbits; experts have added additional diagnostics 
and continue their investigation.  An access was needed to fill the F17K2 
proton injection kicker with fluorinert.

* Low-Beta Optics Measurements (Alex Valishev) - Measurements of the low-beta
lattice were made on the proton helix and, for the first time, on the pbar
helix (simulated with dipole correctors).  The measured beta* at CDF and D0
are consistent with each other.  The proton and pbar helix horz beta* are
equal, but the vert beta* differ by 20% between the proton and pbar helix.  
There is a 6 cm D* (dispersion) at D0 that is large enough to account for the 
observed CDF/D0 luminosity ratio.  The D0 beta* z-position may also differ
between the proton and pbar helix, but the accuracy of that measurement is
poor.  Alex can now model the observed luminosity evolution during stores
with RF station trips by including bunch length and dp/p changes.  Alex
is developing lattice corrections to reduce the D0 D*.

* Single Kick Pbar Emittance Blow-up (Valeri Lebedev) - Valeri compared the 
predicted change in transverse distribution for a bunch kicked by a single
kick or multiple random kicks (as we are doing with the PBJ).  The single kick
method doesn't provide much benefit unless the initial emittances are small
enough (3 pi?) such that a very hard single kick would be needed to create
the desired final emittance.  So, proceeding with the multiple kick PBJ is fine
for now to make larger pbars at flattop.  Implementing bunch-by-bunch kick
amplitudes/durations would still be nice feature to have.

* Plan for Next Week

   - Deliver luminosity
   - AC Dipole Measurements (Ryoichi, proton-only or during shot-setup)
   - Exercise PBJ remote control (end-of-store)
   - Try low-beta corrections when ready (end-of-store first)