Compare positron emission with electron capture.
Positron emission is
of a
that involves the emission
(particle with the same mass as an electron but
opposite charge) from a nucleus. During this process, a
in the nucleus is converted into a neutron and a
is emitted.
positron, and then the
Electron capture is
number of
that decreases the
In unstable nuclei lying below the
This occurs when the nucleus of an atom draws in
usually from the lowest energy
a surrounding
level. The captured electron combines with a
form a
to