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Radioactive Decay
Gamma Decay and Internal Conversion (IC)
For all the decay schemes, the daughter nucleus is in most of the cases in an
γ-rays
daughter
*
daughter
excited energetic state. Its energy excess is usually emitted as γ-rays: these are
photons, having their origin in nucleus and showing
a line energy spectrum
(photons emitted at discrete energies)
. This process of emitting
γ-rays
is called
gamma decay
.
In addition to the γ-ray emission, there is another mechanism by which the
daughter nucleus can loss its energy excess. This is by transferring its energy
excess directly to an inner orbital electron, which then escapes the atom with a
kinetic energy equal to the difference of the nucleus excess energy and the
binding energy of the involved electron. This process is called
internal
conversion (IC)
and the involved electron is called
internal conversion electron
(CE)
.
In both gamma decay and internal conversion process, the atomic number Z, the
mass number A as well as the number of neutrons N in the nucleus remain
unchanged.