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Updated: May 25, 2026

Single-throughput Complementary High-resolution Analytical Techniques for Characterizing Complex Natural Organic Matter Mixtures
Published on: January 7, 2019
Practical limitations on astrophysical observations of methanol to investigate variations in the proton-to-electron
Simon Ellingsen1, Maxim Voronkov, Shari Breen
1School of Mathematics and Physics, University of Tasmania, TAS 7001, Australia. Simon.Ellingsen@utas.edu.au
Abstract:
The possibility of using astrophysical observations of rotational transitions in the methanol molecule to measure, or constrain temporal and spatial variations in the proton-to-electron mass ratio (μ) has recently been investigated by several groups. Here we outline some of the practical considerations of making such observations, including both the instrumental and astrophysical limitations which exist at present. This leads us to conclude that such observations are unlikely to be able to improve evidence either for, or against the presence of variations in the proton-to-electron mass ratio by more than an order of magnitude beyond current limits.
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