Open AccessArtificial radioactivity
Author(s) -
J W T SPINKS
Publication year - 1934
Publication title -
proceedings of the royal society of london. series a, containing papers of a mathematical and physical character
Language(s) - English
Resource type - Journals
eISSN - 2053-9150
pISSN - 0950-1207
DOI - 10.1098/rspa.1934.0149
Subject(s) - radiochemistry , induced radioactivity , proton , neutron , curie , isotope , radionuclide , chemistry , nuclear physics , physics , curie temperature , quantum mechanics , ferromagnetism
The new phenomenon of induced radioactivity discovered by Curie and Joliot presents many points of exceptional interest. It appears that when α-particles collide with aluminium nuclei two different processes may occur. A proton may be ejected Al13 27 + He2 4 → Si14 30 + H1 1 , leaving a stable isotope of silicon. This is the process which has been investigated in great detail, notably by Chadwick and his collaborators. Alternatively a neutron may be ejected instead of the proton leaving an isotope of phosphorus Al13 27 + He2 4 → P15 30 +n 0 1 . This element, calledradio-phorus by its discoverers, Curie and Joliot, disintegrates with emission of positrons with a period of about 3 minutes P15 30 → Si14 30 + ε+ .