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

Swapnil Patel, Kenneth R. Brown

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 ro…