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Sensitivity coefficients to temporal variation of the fine-structure constant alpha for transitions between the fine-structure (FS) sub-levels of the ground states of C I, Si I, S I, Ti I, Fe I, N II, Fe II, O III, S III, Ar III, Fe III, Mg…

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

We report a new constraint on the variation of the fine-structure constant based on the analysis of 15 Si IV doublets selected from a ESO-UVES sample. We find \Delta\alpha/\alpha = (+0.15+/-0.43) x 10^-5 over a redshift range of 1.59< z <…

Astrophysics · Physics 2009-11-10 Hum Chand , Patrick Petitjean , Raghunathan Srianand , Bastien Aracil

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

We consider several transitions between narrow lines that have an enhanced sensitivity to a possible variation of the fine structure constant, alpha. This enhancement may allow a search to be performed with an effective suppression of the…

Atomic Physics · Physics 2009-11-11 S. G. Karshenboim , A. Yu. Nevsky , E. J. Angstmann , V. A. Dzuba , V. V. Flambaum

We present constraints on the spacetime variation of the fine-structure constant $\alpha$ at redshifts $2.5\le z<9.5$ using JWST emission-line galaxies. The galaxy sample consists of 621 high-quality spectra with strong and narrow [O III]…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-22 Linhua Jiang , Shuqi Fu , Feige Wang , Sarah E. I. Bosman , Zheng Cai , Hyunsung D. Jun , Zhiwei Pan , Fengwu Sun , Jinyi Yang , Huanian Zhang

[O III]$\lambda\lambda$4960,5008 doublet are often the strongest narrow emission lines in starburst galaxies and quasi-stellar objects (QSOs), and thus are a promising probe to possible variation of the fine-structure constant $\alpha$ over…

Astrophysics of Galaxies · Physics 2023-10-30 Ge Li , Luming Sun , Xiangjun Chen , Hongyan Zhou

We report a robust constrain on the possible variation of fine-structure constant, alpha = e^2/(hbar*c), obtained using O III 4959,5007, nebular emission lines from QSOs. We find Delta-alpha/alpha=-(2.1 +/- 1.6) x 10^(-5) based on a well…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-18 H. Rahmani , N. Maheshwari , R. Srianand

We calculate sensitivity coefficients to $\alpha$-variation for the fine-structure transitions (1,0) and (2,1) within $^3P_J[2s^2 2p^2]$ multiplet of the Carbon-like ions C I, N II, O III, Na VI, Mg VII, and Si IX. These transitions lie in…

Atomic Physics · Physics 2009-03-10 M. G. Kozlov , I. I. Tupitsyn , D. Reimers

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

Sensitivity of the frequencies of twenty two atomic transitions to the variation of the fine structure constant $\alpha$ is calculated. The findings are to be used in search for possible variation of $\alpha$ across our Galaxy using high…

Atomic Physics · Physics 2022-06-22 V. A. Dzuba , V. V. Flambaum , M. T. Murphy , D. A. Berke

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

Absorption spectroscopy toward high-redshift quasars provides strong constraints on the putative variation of fundamental constants of physics on cosmological time scales. The submillimeter ground-state transitions of methylidyne (CH) and…

Cosmology and Nongalactic Astrophysics · Physics 2026-02-25 S. Muller , A. Beelen , M. Guelin , J. H. Black , F. Combes , H. L. Bethlem , M. Gerin , C. Henkel , K. M. Menten , M. T. Murphy , W. Ubachs , N. Wozny

Dependence of transition frequencies on the fine structure constant $\alpha=e^2/\hbar c$ is calculated for several many-electron systems which are used or planned to be used in the laboratory search for the time variation of the fine…

Atomic Physics · Physics 2009-11-13 V. A. Dzuba , V. V. Flambaum

Theories unifying gravity and other interactions suggest the possibility of spatial and temporal variation of physical ``constants'' in the Universe. Detection of high redshift absorption systems intersecting the sight lines towards distant…

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

Recent theoretical ideas and observational claims suggest that the fine structure constant alpha may be variable. We examine a spectrum of models in which alpha is a function of a scalar field. Specifically, we consider three scenarios:…

High Energy Physics - Phenomenology · Physics 2009-11-10 Charles L. Steinhardt

We propose a new method to probe for variations in the fine structure constant alpha using clusters of galaxies, opening up a window on a new redshift range for such constraints. Hot clusters shine in the X-ray mainly due to bremsstrahlung,…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 Silvia Galli

Aims. We constrain a hypothetical variation in the fundamental physical constants over the course of cosmic time. Methods. We use unique observations of the CO(7-6) rotational line and the [CI] 3P_2 - 3P_1 fine-structure line towards a…

Cosmology and Nongalactic Astrophysics · Physics 2013-06-12 S. A. Levshakov , F. Combes , F. Boone , I. I. Agafonova , D. Reimers , M. G. Kozlov

The comparison of different atomic transition frequencies over time can be used to determine the present value of the temporal derivative of the fine structure constant alpha in a model-independent way without assumptions on constancy or…

Atomic Physics · Physics 2009-11-10 E. Peik , B. Lipphardt , H. Schnatz , T. Schneider , Chr. Tamm , S. G. Karshenboim

A new method for examining the possible space-time variation of the fine structure constant ($\alpha$) is proposed. The technique uses a relatively simple measurement with an optical resonator to compare atom-stabilized optical frequency…

Atomic Physics · Physics 2007-05-23 J. R. Torgerson
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