Tandem Accelerator question

[Catherine H Knox <cathyk@maroon.tc.umn.edu> (Cathy Knox)]

I have my 11yr old  at work with me today, and we will be visiting the old
tandem 
accelerator here at the U of M. Kris has the following question, (which he
typed himself):

        "does anyone have a tamdem accelerator and if so when was it last
used? And if you do have a tamdem accelerator when was it new and how much
did it cost? What did you use it for? And do you now why it was replaced
with the linear accelerator."

Thanks, and I wanted to note answers only need be very basic, I can fill in
some 
of the details.

___________________________
Cathy Knox
Health Science Auditor
Radiation Protection
W-176 Boynton 
University of Minnesota
cathyk@maroon.tc.umn.edu