Constraining the cosmological time variation of the fine - structure constant

Abstract

The variation of the fine-structure constant ? = e2 th{stroke}c can be probed by comparing the wavelength of atomic transitions from the redshift of quasars in the Universe and laboratory over cosmological time scales t ~ 1010 yr. After a careful selection of pairs of lines, the Thong method with a derived analytical expression for the error analysis was applied to compute the ? variation. We report a new constraint on the variation of the fine-structure constant based on the analysis of the CIV, NV, MgII, AlIII, and SiIV doublet absorption lines. The weighted mean value of the variation in ? derived from our analysis over the redshift range 0.4939 ?? z ?? 3.7 is = (0.09 ? 0.07)??10-5. This result is three orders of magnitude better than the results obtained by earlier analysis of the same data on the constraint on ???/?. ?? 2010 Springer Science+Business Media, Inc.