Radiation From Canal Ray Impact

Hydrogen canal rays accelerated in fields up to 40 kv were allowed to impinge on a metal target and the beam of particles and radiation emitted from the target were investigated. Pinhole images of the focal spot were obtained on Schumann plates and plates coated with molybdenum trioxide. The presence of atomic hydrogen was shown by a characteristic light blue color produced on molybdenum trioxide plates. By means of a deflecting magnetic field it was found that the beam from the target consisted mainly of neutral particles (or of radiation) but contained a smaller number of protons whose velocity was practically equal to that of the protons incident on the target. The neutral particles by virtue of their ability to affect a photographic plate could suggest the presence of electromagnetic radiation. A grating was used to detect such radiation. Radiation of wave-length 1216A was excited in the residual gas by the canal ray beam when the pressure was as low as ${10}^{-4\mathrm{}}$ mm of Hg. Any characteristic radiation from the target excited by canal ray impact is too small to be measured.