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what is a ion chamber ?
Hey there, great question! An ion chamber is a device that is typically
used in radiation detectors. The ion chamber is filled with gas of some
sort, and as radiation passes through the chamber, it ionizes some of
the gas. This means that the radiation knocks some of the electrons off
of the gas so that it forms a positively charged part (the gas ions)
and a negatively charged part (the electrons). For example, an atom of
argon gas could be ionized to form a positively charged argon ion (Ar+)
and a free electron. There are two electrodes in the ion chamber; one
at each end. The positively charged electrode is called the anode and
the negatively charged electrode is called the cathode, and they become
charged up when you apply a voltage to them. When the gas in the ion
chamber is ionized by radiation, the positively charged gas ions are
attracted to the cathode and the electrons are attracted to the anode.
This flow of charges is an electric current that can be measured, and
by analyzing this current you can figure out how much radiation is
present! In other words, higher radiation means that more gas is
ionized which means a higher electric current.
Thanks for your question!
(republished on 08/02/06)
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