English
Related papers

Related papers: On Th229 and time-dependent fundamental constants

200 papers

We calculated the contribution of Coulomb energy to the spacing between the ground and first excited state of $^{229}$Th nucleus as a function of the deformation parameter $\delta$. We show that despite the fact that the odd particle is a…

Nuclear Theory · Physics 2009-08-03 V. V. Flambaum , N. Auerbach , V. F. Dmitriev

The lowest-known excited state in nuclei is the 7.6 eV isomer of 229Th. This energy is within the range of laser-based investigations that could allow accurate measurements of possible temporal variation of this energy splitting. This in…

Nuclear Theory · Physics 2008-11-26 A. C. Hayes , J. L Friar , P. Moller

State-resolved laser spectroscopy at the 10$^{-12}$ precision level recently reported in $arXiv$:2406.18719 determined the fractional change in nuclear quadrupole moment between the ground and isomeric state of $^{229}\rm{Th}$, $\Delta…

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

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

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

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

Quasi-forbidden electronic transitions in atoms and quasi-degenerate vibronic transitions in molecules serve as powerful probes of hypothetical temporal variations of fundamental constants. Computation of the sensitivity of a transition to…

Chemical Physics · Physics 2025-11-17 Carsten Zülch , Konstantin Gaul , Robert Berger

A realistic evaluation of Coulomb potential has been made for some selected nuclei using the available model-independent data for the charge density and the recent development of Coulomb energy-density functional. Within the Woods-Saxon…

Nuclear Theory · Physics 2023-03-03 L. Xayavong , Y. Lim

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

The nucleus-nucleus interaction potentials in heavy-ion fusion reactions are extracted from the microscopic time-dependent Hartree-Fock theory for mass symmetric reactions $^{16}$O${}+^{16}$O, $^{40}$Ca${}+^{40}$Ca, $^{48}$Ca${}+^{48}$Ca…

Nuclear Theory · Physics 2008-11-26 Kouhei Washiyama , Denis Lacroix

We perform accurate calculations of the dependence of transition frequencies in two valence electron atoms and ions on a variation of the fine structure constant, alpha. The relativistic Hartree-Fock method is used with many-body…

Atomic Physics · Physics 2009-02-05 E. J. Angstmann , V. A. Dzuba , V. V. Flambaum

We analyze the details of mass exchange in the vicinity of the Coulomb barrier for heavy-ion collisions involving neutron-rich nuclei using the time-dependent Hartree-Fock (TDHF) theory. We discuss the time-dependence of transfer and show…

Nuclear Theory · Physics 2008-11-26 A. S. Umar , V. E. Oberacker , J. A. Maruhn

We present a review of recent works devoted to the variation of the fine structure constant alpha, strong interaction and fundamental masses. There are some hints for the variation in quasar absorption spectra, Big Bang nucleosynthesis, and…

Atomic Physics · Physics 2009-08-18 V. V. Flambaum

The ^{207}Pb^{19}F molecule possesses a pair of closely spaced levels of opposite parity due to near cancelation of the omega-type doubling and magnetic hyperfine interaction energy shifts [Alphei et al., Phys. Rev. A, 83, 040501 (2011)].…

Atomic Physics · Physics 2014-05-08 V. V. Flambaum , Y. V. Stadnik , M. G. Kozlov , A. N. Petrov

We use the relativistic Hartree-Fock method, many-body perturbation theory and configuration-interaction method to calculate the dependence of atomic transition frequencies on the fine structure constant, alpha. The results of these…

Atomic Physics · Physics 2008-11-26 J. C. Berengut , V. A. Dzuba , V. V. Flambaum , M. V. Marchenko

There exist in nature a few nuclear isomers with very low (eV) excitation energies, and the combination of low energy and narrow width makes them possible candidates for laser-based investigations. The best candidate is the lowest-energy…

Nuclear Theory · Physics 2008-11-26 A. C. Hayes , J. L. Friar

We calculate nuclear-polarization energy shifts for hydrogenlike $^{208}_{~82}$Pb$^{81+}$. A retarded transverse part as well as the Coulomb part is taken into account as the electromagnetic interaction between an electron and the nucleus.…

Nuclear Theory · Physics 2009-11-07 Akihiro Haga , Yataro Horikawa , Yasutoshi Tanaka

Spatial and temporal variations in the electron-to-proton mass ratio, mu, and in the fine-structure constant, alpha, are predicted in non-Standard models aimed to explain the nature of dark energy. Among them the so-called chameleon-like…

Cosmology and Nongalactic Astrophysics · Physics 2009-11-20 S. A. Levshakov , I. I. Agafonova , P. Molaro , D. Reimers

We compute primordial light-element abundances for cases with fine structure constant alpha different from the present value, including many sources of alpha dependence neglected in previous calculations. Specifically, we consider…

Astrophysics · Physics 2008-11-26 Kenneth M. Nollett , Robert E. Lopez
‹ Prev 1 2 3 10 Next ›