Franck-Hertz  :   Xenon

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 Code Number :   7B30.12

Disclaimer:

Reprinted by permission of Dick Berg, University of Maryland, for use on this website.

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Condition :   Excellent  
Principle :   Critical Potential in a Gas   
Area of Study :  Modern Physics  
Equipment :   Franck - Hertz Xenon Tube Unit, 0 to 20 VDC Power Supply, 2 - Variacs, 2 - 6 volt Transformers, Volt and Amp Meters, Oscilloscope.

  
Procedure :   This version of the Franck - Hertz experiment is built around the 2D21 electron tube that has an appreciable amount of xenon gas present.  Since we like to show our peak on an oscilloscope instead of plotting it out, our hookup is a little different than that described in the instruction booklet in the files. We impress a 60 cycle, three volt ripple on the 0 to 12 VDC side of the circuit. Run the DC power supply at about 4 to 5 volts. Usually the ripple can be held to around 2 volts when everything stabilizes. The meter amplifier switch must be to Experiment 1 on the Franck - Hertz unit. Some tweaking of the power supply voltages and the control knobs on the Franck - Hertz unit will probably be necessary to obtain the best trace. Only one peak will be obtained with this unit.  
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   References
 

"Ionization Potential of Xenon", AJP, 33 (5), May 1965, p.xvii



Mail Questions and Comments to:  Dale Stille