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Related papers: New limits on variation of the fine-structure cons…

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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

Transition frequencies of atoms and ions are among the most accurately accessible quantities in nature, playing important roles in pushing the frontiers of science by testing fundamental laws of physics, in addition to a wide range of…

We report on the possibility to obtain a high-quality inverted Doppler-free resonance in D1 line of alkali-metal atoms in the single-frequency regime. The counter-propagating optical fields with linear and mutually orthogonal polarizations…

We test the consistency of several independent astrophysical measurements of fundamental dimensionless constants. In particular, we compare direct measurements of the fine-structure constant $\alpha$ and the proton-to-electron mass ratio…

Cosmology and Nongalactic Astrophysics · Physics 2014-05-05 M. C. Ferreira , O. Frigola , C. J. A. P. Martins , A. M. R. V. L. Monteiro , J. Solà

We present new measurements of quantum defects and core polarizabilities in cesium ($^{133}$Cs), based on transition frequency measurements between Rydberg states ($14 \leq n \leq 38$) obtained through terahertz (THz) and radio-frequency…

Atomic Physics · Physics 2025-06-03 Gianluca Allinson , Lucy A. Downes , Kevin J. Weatherill , C. Stuart Adams

The relative effects of variation of the fine structure constant alpha=e^2/hc and dimensionless strong interaction parameter m_q/Lambda_{QCD} are enhanced 5-6 orders of magnitude in very narrow ultraviolet transition between the ground and…

Atomic Physics · Physics 2011-11-23 V. V. Flambaum

QSO absorption spectra provide an extremely useful probe of possible cosmological variation in various physical constants. Comparison of H I 21cm absorption with corresponding molecular (rotational) absorption spectra allows us to constrain…

Astrophysics · Physics 2009-08-18 M. T. Murphy , J. K. Webb , V. V. Flambaum , M. J. Drinkwater , F. Combes , T. Wiklind

We re-examined Shlyakhter's analysis of the Sm data in Oklo. With a special care of minimizing contamination due to the inflow of the isotope after the end of the reactor activity, we confirmed that his result on the time-variability of the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Yasunori Fujii , Akira Iwamoto , Tokio Fukahori , Toshihiko Ohnuki , Masayuki Nakagawa , Hiroshi Hidaka , Yasuji Oura , Peter Moller

Microwave and submillimeter molecular transition frequencies between nearly degenerated rotational levels, tunneling transitions, and mixed tunneling-rotational transitions show an extremely high sensitivity to the values of the…

Atomic Physics · Physics 2016-10-26 M. G. Kozlov , S. A. Levshakov

We explore the potential variation of two fundamental constants, the fine-structure constant $\alpha$ and the proton-to-electron mass ratio $\mu$, within the framework of modified gravity theories and finite-temperature effects. Utilising…

Solar and Stellar Astrophysics · Physics 2025-09-17 Akhil Uniyal , Surajit Kalita , Yosuke Mizuno , Sayan Chakrabarti , Yan Lu

The spectrograph ESPRESSO recently obtained a limit on the variation of the fine-structure constant, $\alpha$, through measurements along the line of sight of a bright quasar with a precision of $1.36$ ppm at $1\sigma$ level. This imposes…

The [O III] $\lambda\lambda\ 4960,5008$ emission lines in the optical spectra of galaxies and quasars have been widely used to investigate the possible variation of the fine-structure constant $\alpha$ over cosmic time. In this work, we…

Cosmology and Nongalactic Astrophysics · Physics 2025-01-08 Jin-Nan Wei , Rui-Jie Chen , Jun-Jie Wei , Martín López-Corredoira , Xue-Feng Wu

Our study is motivated by the prospect of several metastable states in the Sb$ ^{+} $, Au$ ^{+} $, and Hg$ ^{2+} $ ions being used as possible candidates for optical clocks. We calculate several atomic properties relevant to the development…

Atomic Physics · Physics 2023-06-21 Saleh O. Allehabi , V. A. Dzuba , V. V. Flambaum

The bound on the time variation of the fine structure constant ($\alpha$) driven by the dynamics of quintessence scalar field which is coupled to electromagnetism is discussed using phenomenological quintessential models constrained by SNIa…

Astrophysics · Physics 2009-11-10 Da-Shin Lee , Wolung Lee , Kin-Wang Ng

(Abridged) Many-multiplet (MM) method applied to three inhomogeneous samples of Keck/HIRES quasar absorption spectra gives a shift in the value of the fine-structure constant of Delta alpha/alpha = (-5.4+/-1.2) 10^{-6} in the redshift range…

Astrophysics · Physics 2017-08-23 Sergei A. Levshakov

We compare the sensitivity of a recent bound on time variation of the fine structure constant from optical clocks with bounds on time varying fundamental constants from atomic clocks sensitive to the electron-to-proton mass ratio, from…

Cosmology and Nongalactic Astrophysics · Physics 2010-05-26 Thomas Dent

We present calculations of nuclear-spin-dependent and nuclear-spin-independent parity violating amplitudes in Ba, Ra, Ac+, Th and Pa. Parity nonconservation in these systems is greatly enhanced due to the presence of very close electronic…

Atomic Physics · Physics 2014-04-23 B. M. Roberts , V. A. Dzuba , V. V. Flambaum

Precise radial velocity measurements (delta v/c ~ 10^{-7}) of FeII lines in damped Ly-alpha systems from very high quality VLT/UVES spectra of quasars HE0515-4414 and Q1101-264 are used to probe cosmological time dependence of the fine…

A high-precision relativistic calculations of Cd-like Nd$^{12+}$, Sm$^{14+}$ and Sn-like Pr$^{9+}$, Nd$^{10+}$ atomic properties is carried out using an approach that combines configuration interaction and a linearized coupled-cluster…

Atomic Physics · Physics 2015-06-22 M. S. Safronova , V. A. Dzuba , V. V. Flambaum , U. I. Safronova , S. G. Porsev , M. G. Kozlov

We report on spectroscopy of cold dysprosium atoms on the $1001\,\mathrm{nm}$ transition and present measurements of the excited state lifetime which is at least $87.2(6.7)\,\mathrm{ms}$ long. Due to the long excited state lifetime we are…

Atomic Physics · Physics 2020-04-08 Niels Petersen , Marcel Trümper , Patrick Windpassinger
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