Open AccessOn the scattering of Homogeneous β-Rays and the number of Electrons in the Atom
Author(s) -
Jim Crowther
Publication year - 1910
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.1910.0074
Subject(s) - absorption (acoustics) , atom (system on chip) , uranium , gamma ray , atomic number , atomic physics , physics , tin , nuclear physics , chemistry , optics , computer science , organic chemistry , embedded system
The subject of the transmission ofβ -rays through matter has, from time to time, received considerable attention. Apart from any intrinsic interest the problems involved are of considerable theoretical importance. Owing to the high velocity of theβ -rays, the collisions, to which the absorption of the rays must be ascribed, take place not with the atom as a whole, but with its constituent parts, and thus from a study of the behaviour of the rays during their passage through matter we may hope to gain considerable information as to the constitution of the atom. Until very recently it was thought that the phenomena involved in the absorption of theβ -rays were very simple. It was early shown that theβ -rays from a single radioactive substance, such as uranium X for example, were absorbed by light substances, such as aluminium, according to an exponential law. For the heavier elements, such as tin or platinum, the absorption curve at first descended rather more steeply than the true exponential, but finally became exponential after the rays had passed through some small thickness of the absorbing material. This law has been tested for a large number of elements and compounds by the present writer, and with a high degree of accuracy, for a few substances, by N. R. Campbell.