• Main INDEX
  • Monthly INDEX
  • PREV
  • NEXT

    User name Armstrong

    Log entry time 09:03:26 on July 21, 2005

    Entry number 148886

    This entry is a followup to: 148880

    keyword=Note on Septum Heating results

    The latest septum heating results continue to be perplexing!

    Looking at what was obtained from last night at 60% of nominal target density we get a slope for the Right Upper coil of
    (7.256-6.50)/35 µA = 0.0216 K/µA.

    If I compare this to what was obtained after the target was returned to about 101% density I get a slope of
    (7.65-6.50)/35 µA = 0.0328 K/µA.

    The ratio of the slopes is 66%, suggesting this scales linearly with He density.

    BUT

    The slope measured on Sunday July 17 by KK and myself was 0.026 K/µA with nominal density, sweeper on.

    What has made things worse since July 17? Is it the beam, (raster, steering, halo) or something in the cryogenics of the magnet? Why is the heating effect not stable?

    I will look through the data more carefully (i.e. to see if both septa are responding in the same way), but ideas are welcome!

    grumble, grumble, grumble....