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Ernest Rutherford was born on the 30th of August 1871 in Brightwater
near Nelon city in New Zeland. He studied on the University of New Zeland, and then he got
a scholarship in Cambridge. He worked there under the management of
Sir Joseph John Thomson, in the Cavendish Laboratory. In Cambridge
Rutheford conferred a doctor's degree. He was appointed to a professorship on the University of
Montreal. He started to search on radioactive discovering
alpha particle and beta particle. He discovered in 1899 that particles of alpha were
a flux of helium atoms but devoided of electrons. And beta particles are electrons. In 1903 he
published with Frederic Soddy a work
(Frederick Soddy was a British scientist searching on
radioactive; Nobel price 1921). In the work there was a formula
describing radioactivity dependence on time and the proof that
quantity of radioactive disintegration in the sample is
proportional to the quantity of atoms of radioactive substance. Rutheford discovered that
proportionality constant for different elements was rendered by some other constant which he
called radioactivity constant (decay constant). It determined
radioactivity disintegration rate. A year later he ascertained
that decay constant inverse multiplied by some number defined a half-life period-time required to
reduce element's radioactivity in half. He proved that searching
polonium radium for which the half-life period was much shorter than for uranium.
In 1907 he came back to England. He became a professor in Manchester. He
set to study the interaction of alpha rays with matter. With Hans Geiger constructed an instrument
recording alpha particles- spinthariscope. (Hans Geiger
- the constructor of particle counter; the inventor of the empirical law of radioactive disintegration).
Thanks to the spinthariscope Rutheford's assistants (Geiger
and Marsden) managed to observe the occurrence explained
later in 1911 by Rutheford by his new, planetary model of atom.
In 1914 Rutheford proved the wave structure of gamma radiation. In 1919
he moved to Cambridge where he became a director of Cavendish Laboratory. In the same year he
managed to conduct the first in the history artificial nuclear
transformation. Shooting nitrogen atoms by alpha rays he received a new kind of radiation
of the hydrogenium atom mass and positive charge. That was a beam of protons: