Figure 3. (1+1) REMPI spectra recorded under three different conditions. In (a) only NO and Ar were present and the spectrum was recorded in the m/z=16 mass channel; in (b) NO, CH4, and Ar were present, and again the spectrum was recorded in the m/z=16 mass channel; in (c) NO, CH4 and Ar were present, with the spectrum being recorded in the m/z=46 mass channel. See text for details.