The phenomenon investigated in this experiment was whether or not it was possible to excite atoms by low-energy electron bombardment, and to determine if the energy transferred from the colliding electrons were always in discrete amounts. This was investigated using thermally excited electrons that were accelerated across a potential through a homogenous gas of a single element. A slowing potential was applied at the anode making electrons that transferred their energy via inelastic collisions to lose their energy before arriving at the detector, this caused drastic decreases in the current observed. These decreases in current always occurred at the same accelerating potential, which can be interpreted as electrons only being able to transfer discrete amounts of energy to atoms, and this energy correspondingly associates with the allowable energy levels within the atoms.
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