The spatio-temporal rovibrational excitation and relaxation mechanisms of N₂(X) in the post-discharge of a 10ns high-voltage diffuse discharge are studied by spontaneous Raman scattering (SRS). It is shown that the vibrational excitation of nitrogen molecules remains high despite the strong electric fields applied during the discharge itself and the relaxation processes are similar to lower voltage ns discharges. The main differences with the lower field discharges are rather visible at the beginning of the discharge with a specific spatial volume distribution and a significant vibrational non-equilibrium between v = 0, 1 and v > 1. The spatial distribution of the rovibrational excitation of the diffuse discharge is very wide radially, consistent with the sustainability of fields greater than 100 Td over nearly 8mm during propagation. The initial rovibrational excitation is inhomogeneous along the axis. The gas temperature reaches up to about 1200K close to the pin (85 kV, ambient air) while it remains below 500K in the rest of the volume. It is possible to control the heating of the discharge without greatly modifying the energy transfer mechanisms by adjusting the duration of the voltage pulse. In terms of reactivity, high atomic oxygen densities seem to be very localized in the vicinity of the pin (10²⁴m⁻³ at 1.5mm from the pin, corresponding to about 20% dissociation). This inhomogeneity reflects the distribution of energy in the volume of the discharge. The main effects of humidity are also studied. It amplifies the fast heating and accelerates the decay of atomic oxygen in the post-discharge. No significant acceleration of the V–T relaxation of nitrogen due to the addition of water vapour was observed for the studied conditions. A shock wave was identified which is triggered at around 500ns.

N ₂ ( X) 在 10ns 高压扩散放电的后放电中通过自发拉曼散射 (SRS) 进行研究。结果表明，尽管在放电过程中施加了强电场，氮分子的振动激发仍然很高，弛豫过程类似于较低电压 ns 放电。与较低场放电的主要区别在放电开始时相当明显，具有特定的空间体积分布和 v = 0、1 和 v > 1 之间的显着振动非平衡。扩散放电径向非常宽，与传播过程中近 8 毫米范围内大于 100 Td 的场的可持续性一致。初始的振动激励沿轴是不均匀的。靠近引脚的气体温度高达约 1200K（85 kV，环境空气），而在体积的其余部分则保持在 500K 以下。通过调整电压脉冲的持续时间，可以控制放电的加热，而无需极大地改变能量传输机制。在反应性方面，高原子氧密度似乎非常集中在引脚附近（10²⁴ m ^-3在距销钉 1.5mm 处，对应于大约 20% 的解离）。这种不均匀性反映了能量在放电体积中的分布。还研究了湿度的主要影响。它放大了快速加热并加速了后放电中原子氧的衰变。在所研究的条件下，没有观察到由于添加水蒸气而导致的氮的V - T弛豫显着加速。确定了一个冲击波，它在大约 500ns 时被触发。