Hyperfine structure of methanol lines at 25 GHz

2023/10/12 by Vorotyntseva, J. S., Levshakov, S. A.
#Atomic Physics (physics.atom-ph) #Cosmology and Nongalactic Astrophysics (astro-ph.CO) #FOS: Physical sciences

paper · doi:10.48550/arxiv.2310.08231

Abstract

High-dispersion (channel width 0.015 km s^-1) laboratory spectroscopy of the torsion-rotation lines J₂ - J₁ (J = 2 - 6) in the ground torsional state (vt = 0) of the E-type methanol demonstrates multicomponent hyperfine splitting patterns at 25 GHz. The observed patterns are compared with simulations of CH3OH emission lines based on ab initio quantum-mechanical models. A substantial disparity between the laboratory and simulated patterns is revealed. The observed morphology of the line shapes is not reproduced in the model profiles. The found inconsistency requires further refinement of the current quantum-mechanical models to fit the observed hyperfine splitting patterns at 25 GHz.

Related

• Hyperfine structure of the methanol molecule as traced by Class I methanol masers
• Torsion-rotational transitions in methanol as a probe of fundamental physical constants -- electron and proton masses
• Spectroscopic Shifts in Deuterated Methanol Induced by Variation of me/mp
• The Discovery of 25 um Interstellar Methanol
• Submillimeter-wave spectroscopy of the CH₃O radical