Knowledge Bank

Rediative lifetimes have been determined for a number of ultraviolet and vacuum ultraviolet transitions of diatomic and small polyatomic molecules using the phase shift apparatus of $Lawrence1$ with some recent modifications in the electron source. Results will be discussed for about 25 electronic transitions with lifetimes in the range 1-150 nanoseconds in: $H2,N2,N2+CO,CO+,NO,NO+,BF,CF,SiF,CF2$, and $CO2+$ Spectra and lifetimes of emission systems of polyatomic molecules excited in $CF4$ and $BF2$ will also be presented. This work is supported by NASA grant NsG-414. $\mathrm{<mrow\; data-mjx-texclass="ORD">1</mrow>}$ G. M. Lawrence, J.Q.S.R.T. 5, 359 (1965).