Minutes of the Mar 18, 2005 Tevatron Dept Meeting

1. News: DoE Review Mar 29-31; rehearsal Mar 23.

2. XiaoLong on operations: 5 stores, all ended intentionally, Lumi btw 84
and 102; effective emittance in the last 4 stores is ~1pi larger - still
unclear why, longitudinal noise still an issue; pbar losses at seq 24
still hurt D0 - need ideas how to fix it; D0 luminosity monitors corrected
for deadtime and should report +10% higher lumi at start of stores (that's
happened today in the record store #4048 avg=113, CDf=120, D0=106e30).

3. Vladimir reported that introduction of octupoles at 150 has helped:
some 2% of pbars and <1% of protons are saved; positive effect is clearly
seen in the plots of vert. emittance vs pbar loss rate and Pbar intensity
vs proton loss rate (see doc-1740); better chromaticity measurement
techniques are needed for tuneup at 150 (e.g. head-tail).

4. Tan attended a TuneTracker workshop at BNL and learned about the
problems RHIC guys have with the TT if tunes cross each other; he is
convinced that 60 Hz lines in base-band Schottky spectra are real (i.e.,
in beam) - phenomenon we see in the Tev and seen at RHIC.

5. Yuri gave a seminar at BNL and attended RHIC beam studies with Cu-Cu.
He reports that there is a coherent beam-beam instability in RHIC beams at
injection energy similar to what we observe at LB (unstable modes in
separated beams).

6. Ron scaled helix by + and -10% in the middle of the store #4046 and
observed changes in the luminosity lifetime (larger helix -> better
lifetime). Still, better analysis is needed to understand how
beam-beam-induced lifetime depends on the helix size. He also reported tiny
tune changes <0.001 for +-10% scaled helix.

7. Dean showed how to use new Tev studies request Web page (one can go to
Tev main page and try).

8. Jean-Paul reported that longitudinal phase monitor LPM001 is
reconnected at E0 and timed to bunch P1 (since Mar 14); also, confirmed
that no betatron motion is seen in EoS beam position measurement data
taken with digital scope (he and Vic did that 2-3 weeks ago)... even with
VTICK on.


Minutes recorded by V. Shiltsev; edited by R. Moore