7D10.33 - Half-Life of Silver (NO LONGER AVAILABLE)

Code Number:
Demo Title:
Half-Life of Silver (NO LONGER AVAILABLE)
Radioactive Decay, Half-Life
Area of Study:
Modern Physics
Nucleus Model 500 Scaler (2nd Floor), Geiger Tube (2nd Floor), Lead Bricks, Silver Foil, Neutron Howitzer.

The silver foil must be irradiated at least overnight in the neutron howitzer.  The system should be set up as in the pictures and moved into the classroom.  When class has started the instructor should take at least two background radiation checks using the same timing period that will be used during sampling. It is then the job of the Lecture Demonstration Coordinator to get the sample from the neutron howitzer, run down as fast as possible and insert the sample, and begin the count.  This usually takes 30 to 45 seconds.  Counting is usually done for 30 seconds of each minute for 5 to 10 minutes.

The decay should be as follows:

52% of silver is Ag107
Then the reaction for this would be:

47Ag107 + 0N1 → 47Ag108

Then, 47Ag108 → e- + 48Cd108

Ag108  -  2.42m  1/2 life  =  B - decay -  97.5%  -  1.64
MeV, B+ - 2.2% - .90 MeV

48% of silver is Ag109
Then the reaction for this would be:

47Ag109 + 0N1 → 47Ag110

Then, 47Ag110 → e- + 48Cd110

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