Minutes of DRAGON meeting, November 30th, 2004, 10:45
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Present: DH, DO, AO, JP, JC, DG, LB, JD, WH, MT, CV, PM, CR, GR (recorder)

1. Correction to previous minutes
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- Gas target vacuum problem
  DO: Opened the valves and found "black crap" in the valves.

- Q1
  DH: Power went off but the green light stays on.
  Jonty will build in a MIDAS alarm if the current is zero.

- Scaling pages
  Sometimes the scaling pages have a strange user interaction and it would
  be a helpful to have a spreadsheet to check the values.
  Also an "OK" button would be helpful to ensure that the new values are
  actually entered. Christof will make the spreadsheet.

2. Status of the system 
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- XSLITC
  PM: Slits fixed mechanically
  DH: Right/left calibrate buttons perhaps swapped, and one should always
      calibrate both. But at the moment the "left" calibrate button moves the
      slit out and it stays there.
- IC
  CV: Microphonic noise in IC --> tightened some wires --> fixed.
      Noise mainly comes from preamps. Put them into the IC?
  LB: Cooling needed.
  Due to experience with TUDA if the preamps are mounted in the IC, LB
  suggests an interlock then when pumping down and preamps are cooled
  and powered.

3. Status of the run
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- CR: Got only a few hundred pA 28Si(3+) from the source so they switched
    to 29Si(1+).
    Monday: Got a pretty intensive beam of Si28(7+) and no Nitrogen in the
    mass spectra. Current for 7+ was there but no 8+, no 6+ and a tiny bit 9+.
    Obviously, the ions were CO, accelerated as CO(1+) (mass 28) molecule
    plus a bit 28Si(1+). All this went through the RFQ with the same m/q,
    coming out with the same E/u. CO then was broken up by the stripper and
    the magnets selected 12C(3+), 16O(4+) and 28Si(7+), all with the same m/q.
  CV: Decided to test the IC with that C(3+) O(4+) Si(7+) mixture. Since they
    all have the same E/u (rather than the same momentum as for capture
    reactions) and the same m/q, DRAGON can't separate them and they all reach
    the ion chamber. This is a good condition to test the resolution power of
    the IC.
    Result for the 50 nm SiNi windows: Excellent spectra (see attachment). 

4. 12C and 16O charge state distribution
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    Wolf measured CSD for 16O (4+) and 12C (3+) after moving through 4He.
    Pretty nice CSD curves of charges 4+ to 6+ for 12C and 4+ to 8+ for 16O
    Equilibrium of 16O at 0.75 MeV/u is in perfect agreement with the Naples
    measurements 4 years ago.
    The diagrams are attached, except the 3-dimensional plots.
    (Remark: We should buy 3D spectacles for future meetings)

5. 13C tests
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    MT: Filled the test stand ECR with He and then increased the amount of
      13CO2, observed the change in the mass spectrum (see attachment).
      13C is clearly visible, also CO at m/q=29 (and double charged at 14.5)
      and 13CO2 double charged at m/q = 22.5. Silicon is there as well from
      the fact that the plasma can interact with quartz tube, generating Si and SiO

6. AOB
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    - GEANT4 (CR): Some problems with overlapping volumes but not serious
    - EEC rehearsal talks at DRAGON meeting next Tuesday
    - Review of the EMMA project by NSERC visiting committee scheduled for Dec. 17
    - Oak Ridge NL review presented a detailed plan of their research program
      They use 7Be, F and Al competing with DRAGON/TUDA
    - A student of Weiping Liu from China will be coming to work on 11C(p,g)
    - Small talk about TACTIC and the status of TUDA.
        For interested people, see http://tactic.triumf.ca

Meeting ends at 12:00