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VLT/UVES shows no cosmological variability of alpha

P. Molaro·M. Centurion·S. D'Odorico·S. Levshakov
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Abstract

The cosmological variability of alpha is probed from individual observations of pairs of FeII lines. This procedure allows a better control of the systematics and avoids the influence of the spectral shifts due to ionization inhomogeneities in the absorbers and/or non-zero offsets between different exposures. Applied to the FeII lines of the metal absorption systems at zabs = 1.839 in Q1101--264 and at zabs = 1.15 in HE0515--4414 observed by means of UVES at the ESO-VLT, it provides da/a = 0.4 (+/- 1.5 stat)x10^{-6}. The result is shifted with respect to the Keck/HIRES mean da/a = -5.7(+/- 1.1 stat})x10^{-6} (Murphy et al. 2004) at a high confidence level (95%). Full details of this work are given in Levshakov et al (2005)

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P. Molaro, M. Centurion, S. D'Odorico, S. Levshakov. 2005-05-05. VLT/UVES shows no cosmological variability of alpha. https://doi.org/10.1017/s1743921305003078

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