T-474 phone conference

Monday 02 oktober 2006, 09:30 SLAC time, 17:30 UK time

Phone number : +1 510-665-5437
Meeting code : 8343

discussion points

  • magnetic measurements : MMF document (see below) needs to go back in 2 weeks based upon input from Nikolay's simulations & our discussion
    • summary of discussion last ESA phone meeting
       - 10D37 magnets;  ready for re-assembly
       - mag. field probes:
       - SLAC has 4 Type2 and 2 Type 1NMR probes, 2 Hall probes, 1 fluxgate; probes need
         - Dubna to supply additional fluxgate probes
         - plan to install 1 NMR/dipole, 2 Hall probes at D1,D2 and fluxgate probes;
           need to specify exact locations.  Will plan to purchase 1 additional Type 
           2 NMR probe.
       - magnetic measurements: 
         - at mag. measurement lab in november; exact dates unknown.  need to develop test plan;
           starting point for this is MagnetTestPlan document  form to complete, with
           guidance from Morozov's Technote on 10D37 Simulation results
         - also msmts in ESA starting ~mid-nov
       - water cooling:  will use ESA LCW; flow ~3gpm and temp. stability ~1degF
       - power supply and feedback regulation; electrical work needed in Building 108; 
         goal to have power supplies ready for initial testing with magnets in ESA ~Nov. 1
       - interlocks and RunSafe Box; plan 1 RunSafe Box per magnet in series
    • mail from mike concerning the magnets (monday 25-SEPT-2006)
    • Measurement sheet to be sent to MMF
    • Technote with simulation work by Nikolay : TN-2006-2.pdf
  • Calibration tone
  • Electronics for new BPM
  • Mover system :
    • Mike needs input on mover type, encoder, support stand, cable plant, control : SCP ?
    • do we go for same stuff or our own version ?
  • Temperature measurement on new BPM & electronics
    • layout of thermocouples, mike wants to rearrange the thermocouples, one per station, instead of 1 per BPM + one per magnet (5 : 4 dipoles + undulator) that leaves 2 unassigned of the ones currently installed in ESA
    • put one on new electronics ?
    • put additional one on new BPM ??? donno....
    • temperature stability plots (24hrs) in ESA
  • Simulation request from Christina...


Minutes of the T474 phone conference, 02 Oktober 2006

- The 10D37 magnets are basially ready to go. Ray has some intial
  ideas for measurements to put on the MMF (Magnetic Measurement
  Facility). He will send around a first draft which we should comment
  as soon as possible. Target to return the document to MMF around
  16 Oktober.

  o Basically would nee integrated B.dl, which can be done with the
    moving wire system. Probably would have to make this a measurement
    extending to about 1 m outside of the poleshoes as the
    fringefields extend pretty far. Probably usefull to investigate/
    measure what effect the mirrorplates will have.

  o Then also measure the field axially using hall/NMR probes, maybe
    including a small volume of phase space. We can use this to 1 test
    the simulations for uniformity and 2 extrapolate based upon
    Nikolay's simulations to get the field further from axis...

  o Need to measure the temperature coefficient of the magnets. Would
    make sense to have B.dl ready and correct offline the field values
    for temperature.

  o Need to investigate what we will magnetise using the magnets in
    the ESA...

  o Want to operate the magnets at 1/10 of their max. field, so
    Ray is thinking of maybe ramping them up once in saturation and
    then not go beyond 10-15% of their capacity during operation.

  o Ray located some stands for the magnets with some high quality
    precision movers for the magnets, should be no problem to use them.

  o A power supply for the magnets has been identified, and the NMR
    probes should be available at SLAC.

  o Note, the magnets don't have trimcoils on them.

  ---> Highest priority for the magnets now is getting the measurement
       plan in decent shape to pass it on to MMF.

  ---> Ray will come up with a first draft for the document, input
       will be needed.

- Zen is writing the DAQ for the magnets. As we run the magnets in
  series, the control program won't care about 4 individual magnets,
  but will each individual magnet will be monitored with NMR probes.

- Stray fields

  Mark did some plots on stray fields, his results are on :


  *** -------- MAIL FROM RAY ON EARTH FIELD VARIATIONS ------- ***

  Here is the info I have on earth field variations.  Would you
  send it on to the T474 group.  I don't have such a list that
  you seem to use.


    Earth's field = 24,000 to 66,000 nT

      1 Gauss = 1 Oersted = 100,000 nT
      1 gamma = 1 nT

  Earths field has much variation mostly from sun activity.  See
  Figure 1 at  http://www.ips.gov.au/Educational/3/1/2.

  There is a peak at frequencies of hundreds of seconds at about
  100 gamma = 100 nT, which is probably too small for you to see
  on the flux gate. There are also variations of hundreds of nT
  over larger (minutes to hours) time scale that you may be able
  to see.

  Check out:



- Movers :
  Ray will help out with the construction of a support stand, he
  thinks it is best to use the system that was used for Chris'
  BPMs + encoders. The reason why the thing vibrated so much is
  the design of the support stand. Bino will come up with a sketch
  and send around, Ray will help with some CAD drawings.

- Alex is going to MSSL this week to fix some final stuff with the
  BPM design, schematics should go to Ray. First measurments have been
  done using the Al prototype. Initial results are on Alex's eLog :


back to main