论文标题
通过电子碰撞来验证分子离子的旋转冷却
Laser-probing the rotational cooling of molecular ions by electron collisions
论文作者
论文摘要
我们提出了未弹性电子碰撞的旋转冷却和激发速率的状态选择的测量。实验是在低温储存环上进行的，使用单声型电子束在匹配的速度下与ch $^+$ ions的状态敏感激光分解结合使用，以同时监测旋转水平的种群。使用高达600 s的存储时间，我们创建了一种条件，使电子诱导的冷却至$ j = 0 $地基状态在辐射松弛方面占主导地位，从而可以实验确定无弹性电子碰撞速率，从而基于最新的理论计算。在更广泛的范围内，我们的实验为在各种血浆环境中相关的各种分子离子探测非弹性电子碰撞铺平了道路。
We present state-selected measurements of rotational cooling and excitation rates of CH$^+$ molecular ions by inelastic electron collisions. The experiments are carried out at the Cryogenic Storage Ring, making use of a monoenergetic electron beam at matched velocity in combination with state-sensitive laser-dissociation of the CH$^+$ ions for simultaneous monitoring of the rotational level populations. Employing storage times of up to 600 s, we create conditions where electron-induced cooling to the $J = 0$ ground state dominates over radiative relaxation, allowing for the experimental determination of inelastic electron collision rates to benchmark state-of-the-art theoretical calculations. On a broader scale, our experiments pave the way to probe inelastic electron collisions for a variety of molecular ions relevant in various plasma environments.
