Positive Ray Analysis of Ions from a High Frequency Spark

Abstract

This paper gives the analysis by the Thomson parabola method of the positive rays of various materials produced by the high frequency spark method developed by Dempster. The spark materials investigated may be classified into three groups, i.e., metals of high melting point, metals of low melting point and minerals. It was found that almost all the ions obtained were atomic and that most of the elements gave multiply charged ions. The change of charges during the passage from the accelerating field to the analyzing field was also observed. Ions of the elements which exist ordinarily in the gaseous state were obtained from the solid compounds of which these elements form constituents. Helium ions were obtained from the radioactive mineral, cleveite (U${\mathrm{O}}_{2}$\ifmmode\cdot\else\textperiodcentered\fi{}U${\mathrm{O}}_{3}$\ifmmode\cdot\else\textperiodcentered\fi{}PO\ifmmode\cdot\else\textperiodcentered\fi{}Th${\mathrm{O}}_{2}$). From the experiments thus far performed, the high frequency spark method has been shown to be able to give strong sources of multiply charged ions of almost all the elements.