The Messenger 116
June 2004

Constraining the time variation of the fine structure constant

Raghunathan Srianand [1], Patrick Petitjean [2, 3], Hum Chand [1] and Bastien Aracil [2, 4]

[1] IUCAA, Pune, India; [2] Institut d'Astrophysique de Paris – CNRS, France; [3] LERMA, Observatoire de Paris, France;
[4] Department of Astronomy, University of Massachusetts, USA

Abstract: The variation of several fundamental constants in physics can be probed by measuring wavelengths of atomic transitions in the high redshift Universe. In particular any possible variation in the electromagnetic fine-structure constant (α = e²/ℏc) can be detected in the absorption spectra of distant quasars. Using a well defined sample of absorption line systems we derive a 3σ upper limit on the time variation of α of −2.5 × 10^-16 yr^-1 ≤ (Δα / α Δt) ≤ +1.2 × 10^-16 yr^-1.

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The Messenger 116 June 2004

Constraining the time variation of the fine structure constant

Raghunathan Srianand [1], Patrick Petitjean [2, 3], Hum Chand [1] and Bastien Aracil [2, 4]

[1] IUCAA, Pune, India; [2] Institut d'Astrophysique de Paris – CNRS, France; [3] LERMA, Observatoire de Paris, France; [4] Department of Astronomy, University of Massachusetts, USA

The Messenger 116
June 2004

[1] IUCAA, Pune, India; [2] Institut d'Astrophysique de Paris – CNRS, France; [3] LERMA, Observatoire de Paris, France;
[4] Department of Astronomy, University of Massachusetts, USA