No, not really; radioactivity and magnetism are rather different things.
That having been said, radioactivity and magnetism do show up
together in various contexts, and there are some things which are
interesting to talk about.
Some forms of radioactivity (alpha and beta emission, to be
specific) involve the emission of charged particles from atoms which
decay. In alpha decay, a helium nucleus, two protons and two neutrons,
is ejected from the decaying atom. In beta emission, it is an electron
which is emitted. A magnetic field will change the flight paths these
charged particles will follow as they escape the atom, bending them
around in circles, or more generally, helixes (think of a slinky spring
-- that's the shape of a helix. A DNA molecule has two intertwined
helixes).
Another way radioactivity may have something to do with magnetism
is to transform a magnetic material into another via the process of
radioactive decay. 55Fe is an unstable isotope of iron which decays by
an interesting process. The nucleus combines with one of the
inner-shell electrons, turning a proton into a neutron, and emitting a
neutrino in the process. The electrons then rearrange themselves (one's
missing, so another falls down to to take its place), emitting a gamma
ray. The resulting atom is manganese, which is not ferromagnetic by
itself, but can be combined with other metals to make ferromagnetic
alloys. If you start with a pure lump of magnetized 55Fe and wait a
decade or so, the lump will mostly have turned into much less magnetic
manganese.
Tom
(published on 10/22/2007)
