ANTICIPATION OF THE DISCOVERY OF THE NEUTRON

BECK, GUIDO.

Über die Systematik der Isotopen.

Berlin, Julius Springer, 1928. 8vo. Bound in contemporary half cloth with gilt lettering, In "Zeitschrift für Physik", Band 47, 1928. Entire issue offered. Two stamps to title page, otherwise fine. Pp. 407-16 + one folded table. [Entire volume: VII, (1), 914 pp.].

First printing of Beck's important paper in which he anticipates the discovery of the neutron by four years, a seminal contribution to the discovery of the nuclear shell model.

In 1914, Moseley introduced the periodic table and in 1925, Pauli explained the periodicity by enumerating the electrons fitting in shells surrounding the atomic nucleus.
"It became apparent that there are, in general, several different isotopes per element. [...] This was a problem of nuclear physics since isotopes of the same element differ only by their isotopes. A first attempt was made in late 1927 by Beck [the present paper] in Vienna, who compiled a comprehensive table of known isotopes [...] The paper written more than four years before the discovery of the neutron, is remarkable not so much for its results but for two nearly prophetic statements:" (Brandt. The Harvest of a Century, p. 317).

The prophetic statements in the present paper are:

1. "Die einfachste Annahme, die man diesbezüglich machen kann, ist, dass man sich die Kerne, analog wie die Elektronenhülle der Atome, schalenförmig aufgebaut denkt." (i.e. The simplest assumption one can make in this respect it to imagine nuclei, in analogy to the electron hull of atoms, to be built up of shell).

2. "Die Gesetzmässligkeiten der Tabellen lassen aber hoffer, dass das Pauliprinzipund der Spin sich auch auf dem Gebiet der Kerne als Wegweiser bewähren werden." (i.e. The regularities [observed in the table of isotopes] allow to hope that the Pauli principle and the spin will prove of value as guideposts also in the field of nuclei.).

Order-nr.: 49089