Re: Low energy x-ray (8 kev) survey meter

[rkathren@tricity.wsu.edu (Ron L. Kathren)]

Dear Mr. Jo --

The problem might be a little more complex than you might think.  There will
also be bremsstrahlung as well as characteristic x-rays, and the effective
energy of any leakage radiation may well be somewhat higher than the 8 keV
characteristic from Cu, particularly if there is any filtration by the tube
housing.  In any case, the same instrument should serve -- a good low energy
ionization chamber (ie cutie pie) should do the job; several companies,
including Victoreen and Eberline to name 2, make CP's that can do the job.
Remember, diffraction units put out a very small (ie 'pencil') beam with
extremely high intensity, and the beam does not come out parallel to the
floor but is angled slightly downward.  Because of the high intensity, be
extra cautious around the beam port; I've seen several cases of skin burns
from 8 keV diffraction units in my career, and the older units are not
equipped with the same level of safety interlocks as are common on modern units.

Good luck with your measurements.

Ron Kathren, CHP

  

 .  At 05:24 PM 6/5/98 -0500, Mr Jo wrote:
>We have an old but recently assembled  (parts from a number of non-operational
>units) x-ray defraction unit which produce 8 kev x-rays from copper anode.
The x-ray
>unit looks pretty good and tight as far as leakage and beam enclosure is
concerned.
>I used a pan-cake GM to survey for leakage because I did not have
anythingelse.  I
>would like to know what is commercially available to measure
>8 kev x-ray. Thank you and have a good weekend. M. Jo
>========================================================
>Myung Chul Jo, RSO
>EH&S, Mail Stop 328
>University of Nevada, Reno
>Reno, Nevada 89557
>(702)784-4540
>(702)784-4553 fax
>
>
>