Studies of nitrogen self-broadening at high temperature with inverse Raman spectroscopy

We report high-resolution inverse Raman spectroscopy measurements of nitrogen Q-branch linewidths in pure nitrogen at temperatures up to 1500 K and at pressures from 20 to 760 Torr. Transitions from J = 0 to J = 30 have been measured with a resolution of 1.5 × 10−3 cm−1 and a Raman shift accuracy of 1 × 10−3 cm−1. Fits to the data using a Galatry line-shape model provide J-dependent collisional-broadening coefficients. A modified exponential-gap scaling law accurately describes the dependence of these coefficients on temperature and rotational quantum number.