Observations Of The Zeeman/paschen-back Effect In The A-x System Of Crh

Ross, Amanda J.

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https://hdl.handle.net/2142/116858 Copy

Description

Title

Observations Of The Zeeman/paschen-back Effect In The A-x System Of Crh

Author(s)

Ross, Amanda J.

Contributor(s)

• Morin, Julien
• Morville, Jérôme
• Crozet, Patrick

Issue Date

2022-06-23

Keyword(s)

Metal containing

Abstract

We present our investigations of the magnetic response of $\emph{A}^6\Sigma^+$-- $\emph{X}~^6\Sigma^+$ transitions in CrH, in fields up to 0.5 Tesla, focusing on the strong dissymmetry between $\sigma^+$ and $\sigma^-$ transitions, observed as predicted\footnote{Kuzmychov and Berdyugina, Astron. Astrophys. \underline{558}, A120 (2013)} at modest magnetic field strengths. This dissymmetry is recorded as Stokes V signals in telescope spectropolarimetry, where it gives a sensitive probe of stellar magnetism. CrH (and FeH) bands feature prominently in spectra of cool dwarf stars taken for example on the SPIRou spectropolarimeter (searching for exoplanets at the Canada-France-Hawaii telescope). Ultimately, our work should help to discriminate effects of stellar magnetism from exoplanet presence in radial velocity data derived from telescope spectropolarimetric measurements. Field-free line positions are well-documented\footnote{Bauschlicher \textit{et al.}, J. Chem. Phys. \underline{115}, 1312 (2001); Ram \textit{et al.}, J. Mol. Spectrosc. \underline{161} 445 (1993); \newline \indent\hspace{0.2cm}Chowdhury \textit{et al.}, Phys. Chem. Chem. Phys. \underline{8}, 822 (2006); Kleman and Uhler, Can. J. Phys \underline{37} 537 (1959)} for the 760 and 870 nm bands of the $\emph{A}$--$\emph{X}$ system. IR laser magnetic resonance studies\footnote{Lipus \textit{et al.}, Mol. Phys. 73 (5), 1041 (1991)} provide some ground state Land\'e factors, but the Zeeman effect has been investigated for only the lowest rotational levels of the $\emph{A}$ state, under molecular beam conditions\footnote{Chen \textit{et al.}, Phys. Chem. Chem. Phys. \underline{8}, 822 (2006).}. To extend these observations, we have recorded cavity-enhanced absorption data (providing relative intensities in zero field conditions) and laser-induced fluorescence spectra using circularly polarised light, with a discharge source producing CrH at around 500 K.

Publisher

International Symposium on Molecular Spectroscopy

Type of Resource

text

Language

eng

Handle URL

https://hdl.handle.net/2142/116858

DOI

https://doi.org/10.15278/isms.2022.RK05

Copyright and License Information

Copyright 2022 held by the authors

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