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Related papers: A New Option for a Search for Alpha Variation: Nar…

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Aims. To obtain limits on the variation of the fine-structure constant alpha and the electron-to-proton mass ratio mu over different cosmological epochs. Methods. A new approach based on the comparison of redshifts of far infrared (FIR)…

Astrophysics · Physics 2009-09-01 S. A. Levshakov , D. Reimers , M. G. Kozlov , S. G. Porsev , P. Molaro

Searches for spacetime variations of fundamental constants have entered an era of unprecedented precision. New, high quality quasar spectra require increasingly refined analytic methods. In this article, a continuation in a series to…

Cosmology and Nongalactic Astrophysics · Physics 2024-01-03 John K. Webb , Chung-Chi Lee

An attempt is made for a new type of analysis of the time-variability of the fine-structure constant trying to fit the most recent result from the laboratory measurements, the Oklo constraint and the data from the QSO absorption lines all…

Astrophysics · Physics 2009-12-04 Yasunori Fujii

Numerous few-electron atomic systems are considered which can be used effectively for observing a potential variation of the fine-structure constant $\alpha$ and the electron-proton mass ratio $m_e/m_p$. We examine optical magnetic dipole…

Our calculations have shown that the 5f_5/2-7s_1/2 23131 cm^{-1} transition from the ground state in the ion Th^{3+} is very sensitive to the temporal variation of the fine structure constant alpha (q=-75300 cm^{-1}). The line is very…

Atomic Physics · Physics 2010-04-29 V. V. Flambaum , S. G. Porsev

Light scalar Dark Matter with scalar couplings to matter is expected within several scenarios to induce variations in the fundamental constants of nature. Such variations can be searched for, among other ways, via atomic spectroscopy.…

We discuss how laboratory experiments can be used to place constraints on possible variations of the fine structure constant alpha in the observationally relevant redshift interval z ~= 0 - 5, within a rather general theoretical framework.…

Astrophysics · Physics 2009-10-30 Mario Livio , Massimo Stiavelli

Attempts to measure the variability of the fine structure constant alpha over cosmological time, using spectra of high redshift quasars have produced conflicting results. We use the Many Multiplet (MM) method with Mg II and Fe II lines on…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-22 A. Songaila , L. L. Cowie

There are indications from the study of quasar absorption spectra that the fine structure constant $\alpha$ may have been measurably smaller for redshifts $z>2.$ Analyses of other data ($^{149}$Sm fission rate for the Oklo natural reactor,…

High Energy Physics - Phenomenology · Physics 2009-11-10 Luis Anchordoqui , Haim Goldberg

We study a theory in which the electromagnetic field is disformally coupled to a scalar field, in addition to a usual non-minimal electromagnetic coupling. We show that disformal couplings modify the expression for the fine-structure…

Cosmology and Nongalactic Astrophysics · Physics 2015-12-16 Carsten van de Bruck , Jurgen Mifsud , Nelson J. Nunes

We consider transitions of electron holes (vacancies in otherwise filled shells of atomic systems) in multiply-charged ions that, due to level-crossing of the holes, have frequencies within the range of optical atomic clocks. Strong E1…

Atomic Physics · Physics 2011-07-21 J. C. Berengut , V. A. Dzuba , V. V. Flambaum , A. Ong

The detection of a spatial variation of the fine-structure constant, alpha, based on study of quasar absorption systems has recently been reported. The physics that causes this alpha-variation should have other observable manifestations,…

Cosmology and Nongalactic Astrophysics · Physics 2011-06-16 J. C. Berengut , V. V. Flambaum , J. A. King , S. J. Curran , J. K. Webb

We describe the results of a search for time variability of the fine structure constant, alpha, using absorption systems in the spectra of distant quasars. Three large optical datasets and two 21cm/mm absorption systems provide four…

We estimate sensitivity coefficients to variation of the fine-structure constant alpha and electron-to-proton mass ratio mu for microwave Lambda-type transitions in CH molecule and for inversion-rotational transitions in partly deuterated…

Cosmology and Nongalactic Astrophysics · Physics 2009-10-27 M. G. Kozlov , A. V. Lapinov , S. A. Levshakov

We consider different options for the search for possible variations of the fundamental constants. We give a brief overview of the results obtained with several methods. We discuss their advantages and disadvantages with respect to…

Atomic Physics · Physics 2009-11-06 Savely G. Karshenboim

Detection of high-redshift absorption in the optical spectra of quasars have provided a powerful tool to measure spatial and temporal variations of physical ``constants'' in the Universe. It is demonstrated that high sensitivity to the…

Atomic Physics · Physics 2009-10-31 V. A. Dzuba , V. V. Flambaum , J. K. Webb.

Strong evidence has recently emerged for a variation in the fine structure constant, $\alpha\equiv e^2/\hbar c$, over the history of the Universe. This was concluded from a detailed study of the relative positions of redshifted optical…

Astrophysics · Physics 2009-11-10 S. J. Curran , N. Kanekar , J. K. Darling

Detecting or placing upper limits on spacetime variations of fundamental constants requires quantifying every potential source of uncertainty. We continue our previous study into the impact of continuum variations on measurements of the…

Cosmology and Nongalactic Astrophysics · Physics 2024-10-02 John K. Webb , Chung-Chi Lee , Dinko Milaković , Darren Dougan , Vladimir A. Dzuba , Victor V. Flambaum

Comparison of quasar absorption line spectra with laboratory spectra provides a precise probe for variability of the fine structure constant, alpha, over cosmological time-scales. We constrain variation in alpha in 21 Keck/HIRES Si IV…

Astrophysics · Physics 2009-08-18 M. T. Murphy , J. K. Webb , V. V. Flambaum , J. X. Prochaska , A. M. Wolfe

We introduce a methodology to test models with spatial variations of the fine-structure constant $\alpha$, based on the calculation of the angular power spectrum of these measurements. This methodology enables comparisons of observations…

Cosmology and Nongalactic Astrophysics · Physics 2017-04-24 A. M. M. Pinho , M. Martinelli , C. J. A. P. Martins