Collisional narrowing and spectral shift in coherent anti-stokes Raman spectra of molecular nitrogen up to 2500 bar and 700 K

Abstract

CARS spectra of the N2 Q-branch up to 2500 bar and 700 K have been measured. Calculated spectra based on theoretical models show significant disagreement with measured spectra above 300 bar so that CARS temperature measurements are in error by 130 K at 700 K and −150 K at 295 K. The spectral shift of the Q-branch reaches an asymptotic value corresponding to that measured in liquid nitrogen.