Minutes of the Tev Dept Meeting Fri 03/29/02

1. Vladimir informed the Department about recent DoE review where the lab
was criticized for slow Run II start. Ways to deal with that: a) we should
work harder and perform better; and b) we may try to get external help if
the form of - outlined by John Marriner - very clever guys coming to the
lab for short period and making suggestions afterward, getting
few (say 5) scientists from PPD, TD and CD to work on limited scope
projects independently), and, finally, getting several engineers from PPD
to work a year or two (or more...) on Beams stuff.

2. Ron Moore reported the Run II luminosity record of 12.2 in the last
store (#1140). Paul Lebrun shown how pbar lifetime has improved since
we moved hor tune down by 0.002.

3. Vladimir informed about beam parameters correlation
meeting last week (presentation by XLZhang and P.Lebrun).
It was found that at injection pbar bunches #1-4 loose more than others,
at Seq13 bunches #9-12 losses are higher, and at collisions Pbar bunches
1 and 12 have better life time but worse effective emittance.
      Lifetime for bunches 2 and 11 anticorrelates with proton
      intensity while 1 and 12 have zero correlations.
We need to have in SDA
 *  Emittances of all 36 proton and pbar bunches
 *  A marker of bad store so that bad stores could be filtered out if
    necessary
 *  Short store status comments (bad store reason, special conditions,
    etc.)
 *  tunes
Both X.Zhang and P. Lebrun asked to write a TeV note about presented
material.

4. Mike Martens presented results of Seq.15 (old Seq13) experiment:
pbar losses are significantly reduced with
new helix proposed by Yuri (roughly from some 25% to some 8% - for the
same p-intensity). Speed of transition was higher, too (2 sec per step
instead of 5 sec usual) but Mike believes new helix is more important.
What needs to be studied - effects of :a) transition speed; b)
tunes/feedowns, c) position of pbar bunch in train; d) pbar emittances;
e) proton intensities

[My comment: since the new Seq15 helix is introduced we had ]broken Run II
luminosity records in every store. Ops increase proton intensities and
losses at Seq13 grow from 8% to some 13%]

5 Jerry Dean and Bruce performed Tev aperture scans at 150 GeV. The goals
of the scans were a) confirm that C0 is the tightest aperture restriction
and that installation of larger aperture magnets will open significantly
the entire Tevatron aperture; b) confirm that new injection helix proposed
by Yuri is not worse aperture-wise (better?) than the current one [while
beam-beam separation should be larger]. The scans were not complete and to
be continued next week, but so far seems that answers to both a) and b)
are positive.

6. Priorities for studies are set on base of potential luminosity
improvements. Based on the latest stores expectations are:

some 30% may come if we will improve pbar lifetime at 150 GeV (<1hr now)
15-25% from p lifetime at 150 (some 1 hour now)
10-15% if we reduce pbar losses at the beginning of the ramp
10% if we reduce pbar losses during squeeze
5% if we eliminate p-loss at the beginning of the ramp

Next week we perform only studies relevant to these items. There will
be studies time available for smth else (diagnostics, dampers, TEL)
after April 7.