|To further characterize the
rays, Rutherford covered the uranium with metal foils of various
degrees of thickness to see whether the rays would be blocked
by the foil or just pass right through it. While several of the rays
were in fact blocked by the foil, some of them still managed to pass
through with relative ease. This was perhaps the most crucial point
of Rutherford's experiment because it showed that uranium radiation
was composed of two different types of rays: one that was
easily absorbed and another that was more penetrative.
|In 1898 Rutherford published a
scientific article in which he described the existence of the two
different uranium rays. He also termed the easily absorbed
rays as alpha and the more penetrating rays as beta.
Upon additional experimentation, Rutherford discovered that these
rays were actually composed of tiny alpha and beta
|Even though Rutherford worked
with both alpha and beta particles (which were later
identified as being helium nuclei, He^(+2), and electrons; respectively),
his work with alpha particles tends to be emphasized since
they were primary components of several of his more commonly known
experiments. In fact, the foundation for his Gold Foil Experiment
(perhaps one of his greatest scientific achievements) was laid down
when he began measuring the specific charge of alpha particles by
deflecting them in electric and magnetic fields.