[Sneap] Varian CF3000 - Radiation Question

[Daniel Goberman]

Greetings SNEAPers -

    We are trying to bring a Varian CF-3000, 200keV accelerator online after
a few years of inactivity.  When the acceleration energy is increased to any
value above 80keV, we begin to detect X-ray radiation coming from the lens
box and the acceleration column.  At 80 keV the radiation is just above
background levels, but the intensity increase with voltage.  Knowing the
general causes of radiation, we have confirmed good beam focus, strong ion
current on target, electron suppression is working, and the vacuum is about
5x10-7 Torr (in the beamline).
    My questions to the community are:
       1) Were these instruments (CF/DF 3000, DF-4) designed for zero
emissions of radiation?  If so, any thoughts about what could be causing
this particular problem would be welcomed.
       2) If some emissions are expected, does anyone have radiation
measurements for these instruments?  Even rough numbers would be helpful so
that we can decide if this is a problem to be solved or managed.

    Thanks for your thoughts!

     - Dan Goberman :)

-- 
Daniel Goberman, Ph.D.
Laboratory Manager: Surface Science Laboratory
University of Connecticut
Institute of Materials Science
U-Box 3136
Storrs, CT  06269-3136
email: daniel.goberman at uconn.edu
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