The potential of measuring temperature and multiple species concentrations (N<sub>2</sub>, O<sub>2</sub>, CO) by use of combined vibrational coherent anti-Stokes Raman spectroscopy (CARS) and pure rotational CARS has been investigated. This was achieved with only one Nd:YAG laser and one dye laser together with a single spectrograph and CCD camera. From measurements in premixed sooting C<sub>2</sub>H<sub>4</sub>-air flames it was possible to evaluate temperatures from both vibrational CARS and rotational CARS spectra, O<sub>2</sub> concentration from the rotational CARS spectra, and CO concentration from the vibrational CARS spectra. Quantitative results from premixed sooting C<sub>2</sub>H<sub>4</sub>–air flames are presented, and the uncertainties in the results as well as the possibility of extending the combined CARS technique for probing of additional species are discussed.
© 2002 Optical Society of America
(190.1900) Nonlinear optics : Diagnostic applications of nonlinear optics
(280.1740) Remote sensing and sensors : Combustion diagnostics
(300.6320) Spectroscopy : Spectroscopy, high-resolution
Christian Brackmann, Joakim Bood, Per-Erik Bengtsson, Thomas Seeger, Martin Schenk, and Alfred Leipertz, "Simultaneous Vibrational and Pure Rotational Coherent Anti-Stokes Raman Spectroscopy for Temperature and Multispecies Concentration Measurements Demonstrated in Sooting Flames," Appl. Opt. 41, 564-572 (2002)