To speed up the curve-fitting calculation for peak-separation, efficient data division and data reduction techniques were developed on the DLS (damped least-squares) algrithm. According to those techniques, the observed curve is automatically divided to several limits of isolated overlapping peaks. After that the curve-fitting based on the DLS algorithm is carried out for each limits separately with reducing the data by equal-interval samplings. The reduction interval is changed after three iterations to reduce the calculation time, and these intervals were determined from the chi square test of fitting-errors. A visible emission and an IR absorption spectra were separated to several Gaussian and Lorentzian peaks by a personal computer in BASIC language. The calculation time was reduced less than one-third of a conventional DLS method.
Time-of-flight spectra of the Cl photofragments were measured for a molecular beam of p-ClC6H4Cl irradiated by a 193 nm exci mer laser beam polarized parallel or perpendicular to the detection axis. The highest energy component of the observed translational energy distributions of photofragments was sensitive to the polarization direction, strong for parallel polarization and weak for perpendicular polarization. This experimental observation indicates that the highest energy component is attributed to the direct photodissociation channel.
Analysis of the Doppler profile of the excited atomic fragment produced in electron molecule collisions have been found to be useful for the detailed investigation of molecular dissociation dynamics. A new optical instrument has been designed and constructed for such measurements. It has a collision chamber equipped with a rotatable electron gun and a gas cell, and a Fabry-Perot interferometer for a high resolution (0.01-0.07 A) analysis of the line profile. This instrument can successfully allow a determination of the translational energy distribution and the angular difference Doppler profile of the excited atomic fragment, and has been found to be useful and versatile.