Hostname: page-component-78c5997874-xbtfd Total loading time: 0 Render date: 2024-11-02T20:56:47.042Z Has data issue: false hasContentIssue false

Probing the variation of the fine-structure constant using QSO absorption lines

Published online by Cambridge University Press:  06 October 2005

H. Chand
Affiliation:
IUCAA, Post Bag 4, Ganeshkhind, Pune 411 007, India
R. Srianand
Affiliation:
IUCAA, Post Bag 4, Ganeshkhind, Pune 411 007, India
P. Petitjean
Affiliation:
Institut d'Astrophysique de Paris – CNRS, 98bis Boulevard Arago, F-75014 Paris, France
B. Aracil
Affiliation:
Institut d'Astrophysique de Paris – CNRS, 98bis Boulevard Arago, F-75014 Paris, France Present address: Department of Astronomy, University of Massachusetts, 710 North Pleasant Street, Amherst, MA 01003-9305, USA.
Rights & Permissions [Opens in a new window]

Abstract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

Search for the time variation of the fundamental constants is motivated by various unification theories. Here we present constraints on the variation of the fine-structure constant $\alpha$($\equiv {e^2/\hbar c}$) obtained using UVES/VLT samples of QSO absorption systems. We find ${<\Delta\alpha/\alpha}>_{w}={(-0.06\pm0.06)\times10^{-5}}$ using 23 Mg II systems and the many-multiplet (MM) method. Well selected 15 Si IV systems provide ${<\Delta\alpha/\alpha}>_{w}={(0.15\pm0.43)\times10^{-5}}$. Absence of detectable variation in $\alpha$ is also confirmed by our new very high resolution ($R\sim 100,000$) observation of $z_{\rm abs}=1.1508$ toward HE 0515–4414 using HARPS on the ESO 3.6m telescope.

Type
Contributed Papers
Copyright
© 2005 International Astronomical Union