Flame fluorescence excitation profiles

Saturation Broadening in Flames and Plasmas As Obtained by Fluorescence Excitation Profiles... 

Gaussian Laser Profile-Voigt Atom Profile. This case turns out to be a better approximation of our experimental situation, i.e., the laser FWHM is fairly broad compared to the absorption line width and the absorption profile of atoms in an atmospheric combustion flame is described by a Voigt profile. Here the laser is assumed to have a Gaussian spectral profile as well as a Gaussian atomic absorption profile. In this case, convolution of two Gaussian functions is still a Gaussian function. Evaluation of the ratio n2/nT, and the fluorescence radiance. Bp, allows determination of the half width of the fluorescence excitation profile, 6X... 

COMPARISON BETWEEN THE THEORETICAL AND THE EXPERIMENTAL VALUES OF THE FLUORESCENCE EXCITATION PROFILE HALFWIDTHS FOR THE Ar/02/H2 FLAMES.(a) ... 

Figure 12. SH A2X — X2U fluorescence profiles above the burner surface for Hg-Ot-Nt (4 1 6) flames with added HtS (a),l. 0% (b), 0.5% (c), 0.25%. Laser excitation at 323.76 nm with detection at 328.0 nm.

Determination of Flame and Plasma Temperatures and Density Profiles by Means of Laser-Excited Fluorescence... 

The decay trace shown in the upper part of Fig. 4 is obtained following laser excitation of a specific N level in the v =0 level of the state of CH in the burner. Here, the spectrometer which viewed the fluorescence was tuned to 390 nm, the location of the (0,0) band of the B-X system. If the spectrometer wavelength is changed to 413 nm, the trace in the lower panel results. This is fluorescence in the (0,0) and (1,1) bands of the A-X system, produced by CH molecules which have been coUisionally transferred from the B to the A state. Note that the risetime of the A-X emission is the same as the decay of the B-X trace, whereas the A state dies out more slowly, having smaller gq for all flame conditions and the three individual collision partners for which measurements were made. Spatial profiles showing the fluorescence from A caused by collisional transfer fiom B are given in Figs. 2 and 3. 

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