Direct kinetic measurements on reactions of atomic carbon, C(3P), with O2 and NO at temperatures down to 15 K

A CRESU (Cinetique de Reaction en Ecoulement Supersonique Uniforme) apparatus has been used to measure rate coefficients for the reactions of C (P-3) with O-2 and NO at temperatures from 295 K down to 15 K. C (P-3) atoms were, for the first time in a kinetic study, monitored directly by vacuum ultraviolet laser-induced fluorescence. The rate coefficients for both reactions increase as the temperature is lowered, matching the expressions k(C+O-2)=(4.9 +/- 0.8)x10(-11) (T/298 K)(-(0.32 +/- 0.08)) cm(3) molecule(-1) s(-1) and k(C+NO)=(1.5 +/- 0.4)x10(-10) (T/298 K)(-(0.16 +/- 0.14)) cm(3) molecule(-1) s(-1). (C) 2000 American Institute of Physics. [S0021-9606(00)01719-0].