As is now well known there are certain lines in Röntgen spectra which cannot be fitted up into the usual energy level diagram even after violating the selection rules ∆
j
= ± 1, 0, and ∆1 = ±1. These are called “non-diagram” lines or “spark” lines although the latter designation is somewhat anomalous in as much as the usual diagram lines are, regularly, lines due to transitions in an atom deprived of one of the electrons of the completed groups. They are found on the short as well as on the long wave-length side of the principal diagram lines, and consequently it has been customary to describe them as “satellites” of the principal lines. After their first discovery by Siegbahn and Stenström their number has rapidly grown large. Recently Beuthe has measured the β‴ line for elements V (23) to Y (39) and has also discovered a new line
η
for some of these elements. The problem of X-ray spark lines is little understood, and it is desirable to study closely the satellites of the principal lines for many elements in the several series. As a first step towards the achievement of this end a close study of Kα and Kβ satellites of the elements Si (14) to Cl (17) was undertaken. The results obtained go to show that the structure of the satellites is complex and that their nature is highly dependent upon the state of chemical combination of the atom which emits them.
Some investigations in Röntgen spectra. Part I.─X-ray spark lines
