Relative Anfangsbesetzungszahlen der Zustände 2p und 3d folienangeregter Wasserstoffatome
The Lyman-α radiation of fast moving hydrogen atoms excited by a thin carbon foil is measured using a channel electron multiplier with a Mg F2 filter. The photonintensity-versus-distance curve exhibits the 2p (1.596 ns) decay followed by a cascade tail originating mainly from the 3d level (15.47 ns). The data is analyzed by a computer program using the known mean lives of the 2p, 3d, and 3s states and yields the relative initial state populationY=N2p0N3 d0 which depends on the kind of incident ions (H+ or H2+). For H2+ ions, excited with a single foil, there might be a slight dependence ofY on the beam velocity, but for H+ ions incident on the foil, no such dependence is found.