HIGH-RESOLUTION SPECTROSCOPY USING HIGH-ORDER DERIVATIVE TECHNIQUES

A novel technique, employing high-order derivative absorption spectros copy, is used to demonstrate that the resolution of nearly overlapping lines, with disparate oscillator strengths, can be obtained. The meth od employs tunable diode lasers and does not require expensive wavelen gth-resolution apparatus. An experimental demonstration involving near ly overlapping lines of the weak (doubly forbidden by the spin selecti on rule and the lack of an electric dipole oscillator strength) A band of molecular oxygen is provided. The advantages of the method in bein g able to inexpensively monitor the densities (and other properties) o f more than one specie simultaneously, and in the investigation of lin e-shape profiles, are briefly discussed also. (c) 1994 American Instit ute of Physics.