INVESTIGATION OF THE ZEEMAN EFFECT IN THE e ⁶Π −a ⁶∆ SYSTEM OF FeH: APPLICATION TO STELLAR SPECTROSCOPY

Ross, Amanda J.

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Description

Title

INVESTIGATION OF THE ZEEMAN EFFECT IN THE e ⁶Π −a ⁶∆ SYSTEM OF FeH: APPLICATION TO STELLAR SPECTROSCOPY

Author(s)

Ross, Amanda J.

Contributor(s)

• Tokaryk, Dennis W.
• Blackmore, Timothy E
• Adam, Allan G.
• Crozet, Patrick

Issue Date

2023-06-20

Keyword(s)

Small molecules

Abstract

We investigate the Zeeman effect in the e ⁶Π − a ⁶∆ system of FeH. The molecule has been produced by reaction of Fe(CO)₅ with H atoms, and examined by laser excitation with selective detection and by Fourier transform resolved fluorescence. The field-free spectrum of the e ⁶Π − a ⁶∆ system was extensively studied by the J.M. Brown group and collaborators in the 1990’s ᵃ. Their analysis located the low-lying excited a ⁶∆ state 1890 cm−¹ above the X ⁴∆ electronic ground state. One of the infrared systems of FeH already recognisedᵇ in the spectra of cool stars around 1.6 µm, E ⁴Π − A ⁴Π, originates in an excited state lying only 920 cm−¹ lower in energy in energy than a ⁶∆, so it seemed not unreasonable to expect signatures from the known sextet systems e−a and g−a to appear in the spectra of cool stars as well. We found that the e − a system can indeed be used as a diagnostic for FeH. Cross-correlation functions between a mask of laboratory-measured e − a transitions and spectra from four M- dwarf stars taken on spectropolarimetric instruments ESPaDOnS (on Maunakea) and Narval (in the French Pyrenees), show that reliable radial-velocity information can be extracted for these objects. Our new Zeeman measurements are intended to improve reference data for cross-correlation calculations for M-type stars, whose magnetic fields are typically 0 − 5000 Gauss.

Publisher

International Symposium on Molecular Spectroscopy

Type of Resource

Text

Language

eng

Handle URL

https://hdl.handle.net/2142/122395

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