Transition radiation-less

Moreover, there may be additional effects when the ionizing radiation is absorbed in a resonant transition such as the formation of strand breaks by K-shell excitation of phosphorous (Le Sech et al. 1996). 

Le Bourlot et al (1987) have indeed reconsidered the rotational excitation of Cj by solving the equilibrium populations equations (eq. I) with inclusion of the intercombination transitions in the formalism with the recent molecular data reported in 4. They found two different classes of models describing satisfactorily the observations of the first rotational levels of H, and the various rotational levels of C, (figure 3), depending on the value of the interstellar radiation Held, a very critical parameter. 

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