Geiger Muller Tube
Physics and electronics discussion, revision, exam and homework help.
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Geiger Muller Tubecan Gieger muller tubes only be used RELIABLY to dected neutral particles?
charged particles will immidiatley move towards the electrodes and produce a pulse of electricity hence making results unreliable if they ionise a particle on their way as well!!
Also what would happen if the same source of ionising radiation ionised two particles - won't this be detected as two particles by the GM tube even though ONLY 1 is present? -
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Re: Geiger Muller TubeNo, because the voltage in the GM tube is high enough for the charged species produced in the initial ionisation event to gain enough energy that they cause secondary ionisations, and the charged species produced in this way also migrate to the electrode. So an ionisation event triggers an 'avalanche' and a GM tube gives a signal which is not proportional to the energy dissipated.(Original post by ilovemath)
can Gieger muller tubes only be used RELIABLY to dected neutral particles?
charged particles will immidiatley move towards the electrodes and produce a pulse of electricity hence making results unreliable if they ionise a particle on their way as well!!
Also what would happen if the same source of ionising radiation ionised two particles - won't this be detected as two particles by the GM tube even though ONLY 1 is present? -
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Re: Geiger Muller Tubeso does the tube measure the number of pulses of current (i.e: avalanches) and we say that equals (approx) the number of ionising particles of radiation?(Original post by Cora Lindsay)
No, because the voltage in the GM tube is high enough for the charged species produced in the initial ionisation event to gain enough energy that they cause secondary ionisations, and the charged species produced in this way also migrate to the electrode. So an ionisation event triggers an 'avalanche' and a GM tube gives a signal which is not proportional to the energy dissipated. -
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Re: Geiger Muller TubeThat's pretty much it- the more pulses, the more intense the radiation.(Original post by ilovemath)
so does the tube measure the number of pulses of current (i.e: avalanches) and we say that equals (approx) the number of ionising particles of radiation?
