Re: Unknown Sealed Sources

[scherer@uiuc.edu (David Scherer)]

>We have two sealed sources that are labeled Ra-DE. Does anyone know what the DE
>stands for.
>
>Soçe background informatiC6:
>They are paVt of a Beta So8rce Set sold by Don L. Collins & Assoc. ofGlendale,
>CA (1979). Both sources are red-colored, half-disks, which make a 1-inch disk
>when placed side-by-side. They are not labeled with any activity (only Ra-DE),
>but are definitely radioactive (Ra-226, I assume).
>
>I tried contacting Don L. Collins & Assoc., but they do not seem to exist any
>more.
>
>Any help would be greatly appreciated. Thanks...
>
>Michael Cappas
>cappas@mdaw.mdc.com
>
>McDonnell Douglas Aerospace
>Space & Defense Systems
>Huntington Beach, CA
>
>
Just a guess, but it might be Ra D (Pb-210) and Ra E (Bi-210).  The parent
half-life is about 20 y.  The other members of the decay chain would add to
an alpha, but not much to the beta spectrum.

Dave Scherer
scherer@uiuc.edu