Minutes of Tev Fri meeting, April 5, 2002

1. Dept news:
a) Mike Martens and Yuri Alexahin got a "Letter of Recognition" from John
Marriner for their effort to reduce Seq13 losses
b) Aimin Xiao joined the Tev Dept as a Research Associate
c) Ron Moore will coordinate Tev web page business

2. Jerry reported good average luminosity for stores 1142-1154, and very
good L-lifetime for #1154 (17hrs). Store 1144 had record
luminosity for Run II of 13.7e30. Nevertheless, we are more than 2
times below M.Church plan of having some 30e30 on April 15, 2002.
Pbar lifetime was improved by changing pbar horizontal tune.
[Lumi record has been broken again last Saturday  with 14.8e30, store
1174].

3. Valery summarized last week studies of 150 GeV proton lifetime: it's
dependent on how close collimators are (or aperture) and independent of
Tev non-linearities. Seems that separator noises do not matter either.
Studies to be continued.

4. Dean/Jerry and Bruce have finished aperture scans on both new and old
150 GeV helices (for p and pbars). A lot of data collected - need to be
analyzed but preliminary - C0 Lambertsons set tightest aperture
limitation. F0 is the next one. Jerry to make the data analysis and
draw final conclusions.

5. Jerry replaced Mike Martens and reported certain improvement of pbar
lifetime on new 150 GeV helix (3 fold from old 1 hour lifetime).
Implementation of the new 150 GeV helix to be done this week.

6. Jim Steimel and Tan has measured BTF for their longitudinal dampers and
got all the info needed for the damper adjustment (e.g., delays).

7. Vladimir explained what happened with the TEL (HV PS replaced with
smaller one, max current dropped 10 times from 2.5A peak). ).25 A still
can be used for the DC beam cleaning , though the TEL will be less
efficient. TEL will be back to normal operation in about 5-6 weeks.

8. Todd explained what is the CDF complaining about (huge and fast rad
dose  from the abort gap after multiple RF station failure in store 1144).
John Reid has installed RF voltage interlocks to avoid that.

9. Harry Cheung reported successful access to SynckLite. He will use this
week access as well. Vladimir informed that Aimin Xiao will work on
precise determination of betas and D_x at collimators, FWs and SynckLite
to make all three methods of the emittance measurements to agree with
each other.

10. Vladimir informed about last week Tev losses meeting - in general:
what we observe with present collimator configuration is not in a good
agreement with Sasha Drozhdin model [studies to be continued].

After the Tev meeting we discussed:
a) DC beam loss physics with Alvin
b) requirements on the B2 magnets which will replace existing Lamberstons
at C0 (Bruce, Tanaji, Vladimir). Many thanks to Tanaji for thorough
physics consideration. Bruce is preparing that change on high gear to be
ready this fall.