Most precise single redshift bound to the variability of the fine-structure constant
Abstract
Verification of theoretical predictions of an oscillating behavior of the fine-structure constant, alpha, with cosmic time requires high precision measurements at individual redshifts, while in earlier studies the mean Delta alpha/alpha values averaged over wide redshift intervals were usually reported. This requirement can be met via the Single Ion Differential alpha Measurement (SIDAM) procedure. We apply SIDAM to the FeII lines associated with the damped Ly-alpha system observed at z=1.15 in the spectrum of HE0515-4414. The weighted mean calculated on base of carefully selected 34 FeII pairs is <Delta alpha/alpha>=(-0.07+/-0.84)10^{-6}. The precision of this estimate represents the absolute improvement with respect to what has been done in the measurements of Delta alpha/alpha.
Cite
@article{arxiv.astro-ph/0512287,
title = {Most precise single redshift bound to the variability of the fine-structure constant},
author = {S. A. Levshakov and M. Centurion and P. Molaro and S. D'Odorico and D. Reimers and R. Quast and M. Pollmann},
journal= {arXiv preprint arXiv:astro-ph/0512287},
year = {2009}
}
Comments
2 pages, to appear in the Proceed. of IAU Symp.232 "The Scientific Requirements for Extremely Large Telescopes", eds. P. Whitelock, B. Leibundgut, and M. Dennefeld