In the years that preceded the discovery of X-rays, some
physicists observed high-voltage electric discharges in
vacuum tubes. In 1895, the German physicist Wilhelm
Konrad Röentgen studied the same phenomenon in a
Crookes tube [1] operating at high voltage, in a darkened
room. Suddenly, he observed fluorescence (brightness) in a
barium platinocyanide screen placed a few meters from the
tube. He quickly concluded that the fluorescence was caused
by an invisible, unknown radiation, which could completely
pass through solid materials such as paper and wood, once
they did not prevent the fluorescence when placed between
the tube and the screen. He also verified that the radiation
could be stopped by denser materials, such as lead.
đang được dịch, vui lòng đợi..