标题： Ca$^+$和 CaH$^+$铀离子晶体中激发态转动常数的精确测定和黑体辐射测温法 显示英文标题

标题： Precise Determination of Excited State Rotational Constants and Black-Body Thermometry in Coulomb Crystals of Ca$^+$ and CaH$^+$

摘要： 我们展示了高分辨率的钙氢化物分子离子（CaH$^+$）的转动能级和振动能级光谱，这些分子离子与钙离子（$^{40}$Ca$^+$）一起被困在一个库仑晶体中，重点研究了$|X^1\Sigma^+, \nu" = 0> \rightarrow |A^1\Sigma^+, \nu' = 2>$能量组态中的转动跃迁。通过以创纪录的精度解析单个P分支和R分支跃迁，并使用Fortrat分析法，我们提取了激发态$|A^1\Sigma^+, \nu' = 2>$的关键光谱常数，具体包括带源、转动常数以及离心修正值。此外，我们还演示了这里展示的CaH$^+$高分辨率转动光谱作为一种现场探测局部环境温度的应用方法。我们通过观察到的跃迁相对振幅与基础热平衡基态转动分布相关联，并提取出黑体辐射（BBR）温度。 显示英文摘要

摘要： We present high-resolution rovibronic spectroscopy of calcium monohydride molecular ions (CaH$^+$) co-trapped in a Coulomb crystal with calcium ions ($^{40}$Ca$^+$), focusing on rotational transitions in the $|X^1\Sigma^+, \nu" = 0> \rightarrow |A^1\Sigma^+, \nu' = 2>$ manifold. By resolving individual P and R branch transitions with record precision and using Fortrat analysis, we extract key spectroscopic constants for the excited state $|A^1\Sigma^+, \nu' = 2>$, specifically, the band origin, the rotational constant, and the centrifugal correction. Additionally, we demonstrate the application of high-resolution rotational spectroscopy of CaH$^+$ presented here as an in-situ probe of local environmental temperature. We correlate the relative amplitudes of the observed transitions to the underlying thermalized ground-state rotational population distribution and extract the black-body radiation (BBR) temperature.