High resolution opto-acoustic spectroscopy of 15NO: Λ-doubling measurements

We report high-resolution opto-acoustic spectroscopy of v = 0 → 1 vibrational rotational transitions of ¹⁵NO using a low field spin flip Raman laser as the source of tunable infrared radiation. Fifteen transitions belonging to the ²Σ_{$\text{1}\text{2}$} thirteen transitions belonging to ²Π_{$\text{3}\text{2}$} state have been measured and we report the Λ-doubling for the ²Π_{$\text{1}\text{2}$} tran sitions. A preliminary analysis of the Λ-doubling parameters is given.