ROVIBRATIONAL EXCITATION OF H-2-MOLECULES BY HE ATOMS

We present the results of quantum mechanical calculations of cross sec tions and hence rate coefficients for rovibrational transitions in ort ho- and para-H-2, induced by collisions with He. Rovibrational levels up to (v, J) = (3, 8) were included in the calculations. and rate coef ficients are available for temperatures 100 less than or equal to T le ss than or equal to 6000 K. Comparison is made with previous calculati ons of rate coefficients for pure rotational transitions within the vi brational ground state and with measurements of the rate coefficient f or vibrational relaxation v = 1 --> 0 at both high and low temperature s. Agreement is found to be good.