Minutes of the Dec 2, 2005 Tevatron Dept Meeting.

* News (Jerry) - Department (actually the West Booster Tower residence) Christmas party 
will be on December 16.  Also, Vahid received a letter of recognition from Roger Dixon 
for his development of the orbit stabilization program.  This has allowed the experiments 
to run more efficiently and the Tevatron has required less on-call intervention.  The 
Tevatron Dept still needs to plan for 3 low luminosity stores.  There will be 2 stores 
that will collide 1 Proton on 4 Pbars at D0.  This store will be at flattop with separators 
off.  A third low luminosity store will be done at collision optics but with reduced 
brightness.  Since the department meeting it was decided that these store will take place 
in January.  Each of these stores are planned to last 20 to 30 hours.

* Weekly Summary - There was no beam run during the last week because of the the component 
failure at B17.  The vacuum failure was a result of the pressure spike during the quench 
resulting from the B11 Horizontal separator spark.  The bad component was the Spool at 
B17-1A.  The adjacent bypass had damage to its super insulation, but it was determined 
that the bypass could remain in operation.  Changing the bypass would have been a very 
difficult and time consuming job.  The dipole just downstream of the bypass was changed 
as a precaution as it was the weakest (quench current) device in the house.  A more robust 
dipole was put in adjacent to the damaged bypass.  During the qualification hipot, the dipole 
at B11-2 was found to have a sparking ground fault above 600 volts so this dipole was 
replaced as well.  The B11 separator developed a leak on a ceramic feedthrough that 
required letting up the separators.  This repair necessitates a bake, and this will likely 
be the job that determines the length of the Tevatron down time.

Other jobs that will be done during this shutdown include:
IPM/OTR installation
TEL gun, modulator replacement and BPM calibration
B0QT3 polarity change
QPM installation on DQ0
New abort kicker power supplies
repair A48 power lead leak
Other jobs that should have no effect on acclerator operation.

* D0 Low Beta Quad motion instrumentation (Todd) - Some new instrumentation was installed 
on the D0 low beta quad to help diagnose the motion problem.  The air flow monitor shows 
that the temperature change and motion occurs very suddenly when the direction of air flow 
reverses.  Conditions stay much more stable when the hall is kept at positive pressure 
with respect to the tunnel.  Early results from new LVDTs between the quad and the floor 
indicate that the quads move uniformly when reacting to the air flow change.

* Sextupole circuit modification (Alex) - Work has been done to re-orginize the sextupole 
circuits to better control the 2nd order chromaticity.  This is important now, but would be 
even more important if we move the working point near the half integer.  By breaking T:SF and 
T:SD into 4 circuits each we could almost eliminate the chromatic beta beating.  Beam-beam 
problems would be significantly reduced.  The new circuits requires much effort and money, 
so futher work and review will probably continue.

* B11 separator status (Bruce) - Since the vacuum problem that developed during the 
Tevatron safety tests, there have been more problems.  During conditioning, the voltage 
was turned up to 150 KV and this caused too many sparks.  A ceramic HV feedthrough broke 
during the current shutdown. The repair work will need to be followed by a 5 day bake and at 
least 24 hours of conditioning.

* Plans for next week (Jerry) - Finish vacuum work at B1 and begin cooldown.  Repair B11 
separator and begin 5 day bake.  Finish other smaller approved jobs.  At conclusion of 
separator bake, re-connect HV cables and begin conditioning.  For starup, we will probably 
need about 4 shifts.  We will want to tune up the ramp, and parse the squeeze druing 
startup.