Is there a spatial gradient in values of the fine-structure constant? A reanalysis of the results

• Published in: Astronomy and astrophysics (Berlin) Vol. 542; p. A118
• Main Authors: Berengut, J. C., Kava, E. M., Flambaum, V. V.
• Format: Journal Article
• Language: English
• Published: Les Ulis EDP Sciences 01.06.2012
• Subjects: Astronomy; cosmology: miscellaneous; cosmology: theory; Earth, ocean, space; Exact sciences and technology; large-scale structure of Universe; methods: statistical; Quasars; Dipoles; Domain walls; large-scale structure of Universe; Abundance; cosmology: miscellaneous; Large-scale structure; cosmology: theory; Statistical method; methods: statistical; Monopoles; Fine structure constant; Cosmology; Models
• ISSN: 0004-6361; 1432-0746
• DOI: 10.1051/0004-6361/201219286

We statistically analyse a recent sample of data points measuring the fine-structure constant α (relative to the terrestrial value) in quasar absorption systems, where a spatial gradient in α was recently reported. We find agreement with previous authors that the dipole model is a robust, well-justified fit to the data. Using a simple analysis we find that the monopole term (the constant offset in Δα/α) may be caused by non-terrestrial magnesium isotope abundances in the absorbers. Finally we test the domain-wall model against the data.