Search NASA⌕ Search

Engineering topics

Junker, B. R.

Publications and source records attributed to Junker, B. R..

Projection-operator calculations of the lowest e(-)-He resonance

The 1s (2s)2:2S Schulz resonance of He(-) is investigated theoretically, applying the full projection-operator formalism developed by Temkin and Bhatia (1985) in a Rayleigh-Ritz variational calculation. The technique is described in detail, and results for five different approximations of the He target state are presented in a table. Good convergence is obtained, but it is found that even the best calculated value of the resonance is about 130 meV higher than the experimentally measured value of 19.367 + or - 0.007 eV (Brunt et al., 1977), a discrepancy attributed to the contribution of the shift in the Feshbach formalism.

Berk, A.↗

Dissociative recombination of CH+ ions.

In recent studies of the formation of molecules in interstellar clouds, Solomon and Klemperer (1972) and Frisch (1972) were able to fit the observed ratios of CH+ and CH densities only with the assumption that the rate of dissociative recombination is extremely small. It is known that the rate for most diatomic molecules is relatively large, with the exception of H2+ and He2+ for which it is anomalously small. The present work explores the possibility that CH+ also has a low recombination rate. However, preliminary calculations yield a large rate of the dissociative recombination process, seemingly necessitating considerable revision of some recent models of interstellar clouds.

Bardsley, J. N.↗