EM, magnetic fields,x-rays

["Robert R. Milwicz" <MILWICZ%PUCC.bitnet@vmd.cso.uiuc.edu>]

While you are talking about bending VDT displays with magnetic fields,
tell me if you heard this story about magnetic fields, an electron
microscope and x-ray production.  The story goes: A researcher in
Philadelphia noticed x-rays were being detected in his work area when
his electron microscope was operating.  BUT, it was not consistent.
His investigation found that the x-ray leakage was detected only when
the electric trolley car was passing his lab which was next to the
trolley line.  Is this story true or false?  The reason for the
leakage was due to the fact that the magnetic field from the trolley
motor was distorting the microscope's electron beam and caused x-ray
to leak out because the beam was misaligned and the shield was not
adequate as designed.  Thise could be an old story when EM's were not
too well shielded.  Sound too strange to be true story.  Well, I have
measured x-ray leakage from a device called a Luminoscope.  It is
essentially an electron beam that is controlled by small Radio Shack
size magnets.  If the magnets are not properly positioned the electrom
beam hits the sample chamber walls and produces low energy x-ray
leakage because of the way the sample chamber port is constructed.
Leakage was of course dependent on the applied voltage.  So, the
bottom line of my message is this.  If the story about x-rays,
magnetic fields and electron microscopes is true, and if I could see
x-ray leakage from a Luminoscope when the magnets are not properly
aligned, then the question is: Is it possible to have high magnetic
fields distort electron beams so that the distorted beam is hitting
an area of an electronic device for which the designer has not
considered x-ray leakage as a problem because the "electron beam would
not be hitting that area?"  Just a thought for a Friday afternoon.