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Related papers: Fine-structure constant sensitivity of the Th-229 …

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Peik and Tamm [Europhys. Lett. 61, 181 (2003)] proposed a nuclear clock based on the isomeric transition between the ground state and the first excited state of thorium-229. This transition was recognized as a potentially sensitive probe of…

Atomic Physics · Physics 2021-01-19 Pavel Fadeev , Julian C. Berengut , Victor V. Flambaum

The 7.6 eV electromagnetic transition between the nearly degenerate ground state and first excited state in the Th-229 nucleus may be very sensitive to potential changes in the fine-structure constant, $\alpha = e^2/\hbar c$. However, the…

Atomic Physics · Physics 2010-04-22 J. C. Berengut , V. A. Dzuba , V. V. Flambaum , S. G. Porsev

High accuracy measurements in M\"ossbauer transitions open up the possibility to use them in the search for temporal and spatial variation of the fine-structure constant $\alpha$, quark mass $m_q$, and dark matter field which may lead to…

Nuclear Theory · Physics 2022-06-08 Pavel Fadeev , Julian C. Berengut , Victor V. Flambaum

Quantum state-resolved spectroscopy of the low energy thorium-229 nuclear transition was recently achieved. The five allowed transitions within the electric quadrupole structure were measured to the kilohertz level in a calcium fluoride…

We describe a novel approach to directly measure the energy of the narrow, low-lying isomeric state in $^{229}$Th. Since nuclear transitions are far less sensitive to environmental conditions than atomic transitions, we argue that the…

Atomic Physics · Physics 2010-02-09 Wade G. Rellergert , D. DeMille , R. R. Greco , M. P. Hehlen , J. R. Torgerson , Eric R. Hudson

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

Accurate measurements of different transition frequencies between atomic levels of the electronic and hyperfine structure over time are used to investigate temporal variations of the fine structure constant $\alpha$ and the…

Atomic Physics · Physics 2014-12-01 N. Huntemann , B. Lipphardt , Chr. Tamm , V. Gerginov , S. Weyers , E. Peik

The isotope $^{229}$Th is unique in that it possesses an isomeric state of only a few eV above the ground state, suitable for nuclear laser excitation. An optical clock based on this transition is expected to be a very sensitive probe for…

We study ultranarrow $5s_{1/2}$ - $4f_{5/2}$ transitions in Nd$^{13+}$ and Sm$^{15+}$ and demonstrate that they lie in the optical region. The transitions are insensitive to external perturbations. At the same time they are sensitive to the…

Atomic Physics · Physics 2015-06-11 V. A. Dzuba , A. Derevianko , V. V. Flambaum

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

Solid-state $^{229}$Th nuclear clocks are set to provide new opportunities for precision metrology and fundamental physics. Taking advantage of a nuclear transition's inherent low sensitivity to its environment, orders of magnitude more…

Theories unifying gravity with other interactions suggest spatial and temporal variation of fundamental "constants" in the Universe. A change in the fine structure constant, alpha, could be detected via shifts in the frequencies of atomic…

Cosmology and Nongalactic Astrophysics · Physics 2015-05-20 J. C. Berengut , V. A. Dzuba , V. V. Flambaum , J. A. King , M. G. Kozlov , M. T. Murphy , J. K. Webb

Evidence that the fine structure constant, alpha, was different in an early epoch has recently been found in quasar (QSO) absorption spectra. An accurate laboratory measurement of alpha variation could help to distinguish between space and…

Atomic Physics · Physics 2016-09-08 E. J. Angstmann , V. A. Dzuba , V. V. Flambaum

The electromagnetic transition between the almost degenerate 5/2+ and 3/2+ states in Th229 is deemed to be very sensitive to potential changes in the fine structure constant alpha. State of the art Hartree-Fock and Hartree-Fock-Bogoliubov…

Nuclear Theory · Physics 2009-08-18 Elena Litvinova , Hans Feldmeier , Jacek Dobaczewski , Victor Flambaum

Theories unifying gravity with other interactions suggest spatial and temporal variation of fundamental ``constants'' in the Universe. A change in the fine structure constant, alpha, could be detected via shifts in the frequencies of atomic…

Sensitivity to temporal variation of the fundamental constants may be strongly enhanced in transitions between narrow close levels of different nature. This enhancement may be realized in a large number of molecules due to cancelation…

Atomic Physics · Physics 2008-11-26 V. V. Flambaum , M. G. Kozlov

After nearly fifty years of searching, the vacuum ultraviolet $^{229}$Th nuclear isomeric transition has recently been directly laser excited [1,2] and measured with high spectroscopic precision [3]. Nuclear clocks based on this transition…

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 study atomic systems that are in the frequency range of optical atomic clocks and have enhanced sensitivity to potential time-variation of the fine structure constant, alpha. The high sensitivity is due to coherent contributions from…

Atomic Physics · Physics 2010-09-16 J. C. Berengut , V. A. Dzuba , V. V. Flambaum

We calculate hyperfine structure of $^{229}$Th and its ions (Th~IV, Th~III, Th~II, Th~I) to reveal the dependence of the nuclear clock frequency on the hyperfine interaction (hfi). We calculate first and second-order hfi shifts and…

Atomic Physics · Physics 2023-12-18 V. A. Dzuba , V. V. Flambaum
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