High-resolution far ultraviolet emission spectra of electron-excited molecular deuterium

The high-resolution (full width at half maximum Delta lambda = 0.11 Angstro m) emission spectrum of the deuterium molecule produced by electron-impact excitation at 100 eV has been measured in the wavelength range 1200-1660 An gstrom. In conjunction with the experimental measurement, transition probab ilities of B (1)Sigma(u)(+)-X (1)Sigma(g)(+), C-1 Pi(u)-X (1)Sigma(g)(+), B ' (1)Sigma(u)(+)-X (1)Sigma(g)(+) and D (1)Pi(u)-X (1)Sigma(g)(+) band syst ems are calculated. Synthetic spectra based on the calculated transition pr obabilities are in very good agreement with the optically thin experimental spectra. While centrifugal effects on the overall Lyman band emission inte nsity in D-2 and H-2 are similar, the effect of rotation-vibrational pertur bations between the B (1)Sigma(u)(+) and C (1)Pi(u)(+) states on spectral i ntensities is found to be less significant in D-2. Excitations via isotropi c (Delta J = 0) and anisotropic (Delta J = +/-2, and 0) interactions for th e dipole forbidden E,F (1)Sigma(g)(+)-X (1)Sigma(g)(+) transition are infer red from the measured spectra. Excitation cross sections of the B (1)Sigma( u)(+)-X (1)Sigma(g)(+) and C (1)Pi(u)-X (1)Sigma(g)(+) bands, along with th e estimated E, F (1)Sigma(g)(+)-B (1)Sigma(u)(+) cascade cross section, for D-2 are obtained.