Author/Authors :
Aoiz، نويسنده , , F.J. and Ba?ares، نويسنده , , L. and Herrero، نويسنده , , V.J. and Mart??nez-Haya، نويسنده , , B. and Menéndez، نويسنده , , M. and Quintana، نويسنده , , P. and Tanarro، نويسنده , , I. and Verdasco، نويسنده , , E.، نويسنده ,
Abstract :
The rotational relaxation of N2 in collisions with He has been investigated in free jets with a combination of resonance-enhanced-multiphoton ionization spectroscopy and time-of-flight techniques. From the measured data, a global cross-section for rotational relaxation has been derived. The cross section grows from a value of ≈8 Å2 at 100 K to ≈18 Å2 at 5–15 K. For the weakest supersonic expansions investigated, a breakdown of the translational equilibrium between He and N2 has been observed, that could be well accounted for by an isentropic jet model and classical collision cross-sections.
