Rotational level dependent quenching of theAthinsp;3Pgr;i,vrsquo;=0 state of NH

摘要

Quenching cross sections sgr;Qhave been measured for several rotational levelsNrsquo;in theAthinsp;3prod;i,vrsquo;=0 state of NH, for a variety of collision partners. Ground state NH was generated in a room temperature discharge flow and excited with a pulsed laser, and the time decay of fluorescence was measured. The radiative lifetime for the levelsNrsquo;=1 to 5 is 418 plusmn; 8 ns. The sgr;Qrsquo;s are generally large, up to 90 Aring;2, and decrease with increasingNrsquo;. This indicates the influence of an anisotropic, attractive interaction in most but not all cases. The present values of sgr;Qare compared with those of other experiments; because sgr;Qdepends both on Nrsquo;and collision energy, experimental conditions must be carefully specified to yield results which are readily comparable.