I have started reading the theory behind the working of Geiger Muller tube.

I dont understand the concept of pulse!

According to wikipedia:

The ionization is considerably amplified within the tube by the Townsend discharge effect to produce an easily measured detection pulse, which is fed to the processing and display electronics

According to a paper by "cpp.edu":

The electrons that were knocked out of the atom are attracted to the positive electrode, and the positively charged ions are attracted to the negative electrode. This produces a pulse of current in the wires connecting the electrodes, and this pulse is counted.

You can say that an Electro Magnetic Pulse is a short burst of Electro magnetic energy.

In similar terms,if possible,What is this pulse of current?


Wikipedia page:


Paper by "cpp.edu":


  • $\begingroup$ Positive ion drift speeds are generally many orders of magnitude slower than electron drift speeds, meaning that ion pulses are not only harder to get to multiply but also more subject to poisoning by contaminants in the ionization medium. The result is that most detector systems (including but not limited to GM tubes) system make no attempt to use ion drift pulses. $\endgroup$ Commented Nov 25, 2018 at 22:54

1 Answer 1


Imagine that a battery is attached to a loop of wire , with an ammeter and a switch in series. When the switch is closed, current flows through the loop and is indicated on the ammeter. When the current stops and the ammeter reads "zero". Do that quickly enough, and you will refer to the current as a "pulse" of current. In a Geiger-Muller tube, a charged particle passing through the gas of the tube knocks electrons free from atoms in the gas along its path, and thus briefly creates a conductive path that allows current to flow. The particle effectively flips a switch quickly on then off. If that were the whole story, the resulting current pulse would be very small. But the high voltage across the gas in the tube accelerates the electrons freed by the passing charged particle so that they, too, knock some electrons loose from atoms in the gas; and those electrons contribute to the amount of current in the pulse.

  • $\begingroup$ You've introduced pulse to me as a sudden on and off of the current in a wire and thus relating it to the flow of electrons in a wire.But,later :**In a Geiger-Muller tube, a charged particle passing...**,you' were talking about the flow of electrons in the gas,not in the wires connecting anodes .How does G.M tube record the sudden on and off of electron flow(pulse) in the gas?...What I'm asking is how do we know that there was a sudden on and off of electron flow(pulse) in the gas while we can only know if there was sudden on and off of electron flow(pulse) in the wire? $\endgroup$ Commented Nov 25, 2018 at 15:00
  • $\begingroup$ I see the misunderstanding. Go back to the wire loop, switch, and ammeter analogy. A switch connects and disconnects two wire ends. In the case of the G-M tube, after a conductive path through the gas is briefly created by electrons released by the charged particle, current can flow from one wire end to the other wire end across the gas. One wire end is the anode; the other wire end is the cathode. See the illustrations in the wikipedia article. $\endgroup$
    – S. McGrew
    Commented Nov 25, 2018 at 19:39

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