Low pressure surfaguide microwave discharge working in pulsed regime and used for CO₂ conversion is characterized by optical spectroscopy methods aiming at better understanding of the conversion process. The rotational, vibrational, and electron excitation in plasma were studied. The translational (T_gas) and vibrational (T_vibr) temperatures are found elevated in the discharge active zone. At low pressure ($<$1 Torr) discharge demonstrates non-equilibrium with T_gas$\sim$ 700 K (0.06 eV) and electron temperature (T_e) of nearly 2 eV. Non-equilibrium state gradually disappears as the gas pressure increases, resulting in a growth of T_gas and decrease of T_e. T_vibr of nitrogen also slowly decreases towards the equilibrium condition. The CO₂ conversion and energy efficiencies have been examined as a function of the discharge pulse parameters, such as the plasma pulse duration, repetition rate and duty ratio, clarifying additional possibilities for optimization of conversion in the pulsed microwave discharges.

低压表面超导微波放电以脉冲方式工作并用于CO ₂转化，其特征在于旨在更好地了解转化过程的光谱学方法。研究了等离子体中的旋转，振动和电子激发。发现在放电活性区中，平移温度（T _gas）和振动温度（T _vibr）升高。在低压下$<$1 Torr）放电表明与T_气体不平衡$〜$700 K（0.06 eV）和电子温度（T _e）接近2 eV。随着气体压力的增加，非平衡态逐渐消失，导致T_气体的增加和T _e的减少。氮的T _vibr也朝着平衡状态缓慢降低。已根据放电脉冲参数（例如等离子脉冲持续时间，重复频率和占空比）对CO ₂转化率和能量效率进行了检查，从而阐明了优化脉冲微波放电中转化率的其他可能性。