MARVEL analysis of the measured high-resolution rovibronic spectra of the calcium monohydroxide radical (CaOH)

Abstract

The calcium monohydroxide radical (CaOH) is an important astrophysical molecule relevant to cool stars and rocky exoplanets, amongst other astronomical environments. Here, we present a consistent set of highly accurate rovibronic (rotation-vibration-electronic) energy levels for the five lowest electronic states ($\tilde{X}{}^2{\Sigma }^{+}$, $\tilde{A}{}^2\Pi$, $\tilde{B}{}^2{\Sigma }^{+}$, $\tilde{C}{}^2\Delta$, $\tilde{D}{}^2{\Sigma }^{+}$) of CaOH. A comprehensive analysis of the published spectroscopic literature on this system has allowed 1955 energy levels to be determined from 3204 rovibronic experimental transitions, all with unique quantum number labelling and measurement uncertainties. The dataset covers rotational excitation up to $J=62.5$ for molecular states below 29\,000~cm${}^{-1}$. The analysis was performed using the MARVEL algorithm, which is a robust procedure based on the theory of spectroscopic networks. The dataset provided will significantly aid future interstellar, circumstellar and atmospheric detections of CaOH, as well as assisting in the design of efficient laser cooling schemes in ultracold molecule research and precision tests of fundamental physics.

References in corpus (8)

• A search for TiO in the optical high-resolution transmission spectrum of HD 209458b: Hindrance due to inaccuracies in the line database
• Marvel analysis of the measured high-resolution rovibrational spectra of H2S
• MARVEL analysis of the measured high-resolution rovibronic spectra of ${}^{48}$Ti${}^{16}$O
• ExoMol molecular line lists X: The spectrum of sodium hydride
• MARVEL analysis of the measured high-resolution rovibrational spectra of C2H2
• Laboratory spectra of hot molecules: data needs for hot super-Earth exoplanets
• Determination of CaOH and CaOCH${}_3$ vibrational branching ratios for direct laser cooling and trapping
• MARVEL analysis of the measured high-resolution spectra of ${}^{14}$NH

Cited by in corpus (6)

• The 2020 release of the ExoMol database: molecular line lists for exoplanet and other hot atmospheres
• Data availability and requirements relevant for the Ariel space mission and other exoplanet atmosphere applications
• ExoMol line lists -- XLVII. Rovibronic molecular line list of the calcium monohydroxide radical (CaOH)
• Theoretical rovibronic spectroscopy of the calcium monohydroxide radical (CaOH)
• Determination of approximate quantum labels based on projections of the total angular momentum on the molecule-fixed axis
• Low-$J$ transitions in ${\tilde{A}}^2\Pi (0,0,0)-{\tilde{X}}^2{\Sigma }^{+}(0,0,0)$ band of buffer-gas-cooled CaOH