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Probing the time-variation of the fine-structure constant: Results based on Si IV doublets from a UVES sample

Hum Chand·Patrick Petitjean·Raghunathan Srianand·Bastien Aracil
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Abstract

We report a new constraint on the variation of the fine-structure constant based on the analysis of 15 Si IV doublets selected from a ESO-UVES sample. We find Δα/α= (+0.15+/-0.43) x 10^-5 over a redshift range of 1.59< z < 2.92 which is consistent with no variation in α. This result represents a factor of three improvement on the constraint on Δα/αbased on Si IV doublets compared to the published results in the literature. The alkali doublet method used here avoids the implicit assumptions used in the many-multiplet method that chemical and ionization inhomogeneities are negligible and isotopic abundances are close to the terrestrial value.

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Hum Chand, Patrick Petitjean, Raghunathan Srianand, Bastien Aracil. 2004-10-08. Probing the time-variation of the fine-structure constant: Results based on Si IV doublets from a UVES sample. https://doi.org/10.1051/0004-6361%3A20041186

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