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The pion-nucleon coupling constants determine the strength of the long-range nuclear forces and play a fundamental part in our understanding of nuclear physics. While the charged- and neutral-pion couplings to protons and neutrons are…

Nuclear Theory · Physics 2021-03-10 P. Reinert , H. Krebs , E. Epelbaum

A new method for extracting force constants (FC) from first principles is introduced. It requires small supercells but very accurate forces. In principle, provided that forces are accurate enough, it can extract harmonic as well as…

Materials Science · Physics 2007-10-31 Keivan Esfarjani , Harold T. Stokes

Spectra in astroparticle physics are commonly approximated by simple power laws. The steeply falling nature of these power laws, however, makes the detection of additional components rather challenging. This holds true especially, if the…

High Energy Astrophysical Phenomena · Physics 2021-09-22 Tim Ruhe , Wolfgang Rhode

Neutrino-nucleus elastic scattering is reduced in dense matter because of correlations between ions. The static structure factor for a plasma of electrons and ions is calculated from Monte Carlo simulations and parameterized with a least…

Astrophysics · Physics 2016-08-24 C. J. Horowitz

Theoretical predictions underlying determinations of the fine structure constant alpha and the electron-to-proton mass ratio m_e/m_p are reviewed, with the emphasis on the bound electron magnetic anomaly g-2. The theory of the interaction…

High Energy Physics - Phenomenology · Physics 2010-12-13 Andrzej Czarnecki , Matthew Dowling , Jorge Mondejar , Jan H. Piclum

In a recent publication [Ferreira {\it et al.}, Phys. Rev. D89 (2014) 083011] we tested the consistency of current astrophysical tests of the stability of the fine-structure constant $\alpha$ and the proton-to-electron mass ratio…

Cosmology and Nongalactic Astrophysics · Physics 2015-06-12 M. C. Ferreira , C. J. A. P. Martins

We discuss present and future cosmological constraints on variations of the fine structure constant $\alpha$ induced by an early dark energy component having the simplest allowed (linear) coupling to electromagnetism. We find that current…

Cosmology and Nongalactic Astrophysics · Physics 2011-08-08 Erminia Calabrese , Eloisa Menegoni , C. J. A. P. Martins , Alessandro Melchiorri , Graca Rocha

The use of high-precision measurements of the $g$ factor of few-electron ions and its isotope shifts is put forward as a probe for physics beyond the Standard Model. The contribution of a hypothetical fifth fundamental force to the $g$…

Atomic Physics · Physics 2019-01-23 V. Debierre , C. H. Keitel , Z. Harman

Electrons in graphene behave like Dirac fermions, permitting phenomena from high energy physics to be studied in a solid state setting. A key question is whether or not these Fermions are critically influenced by Coulomb correlations. We…

Strongly Correlated Electrons · Physics 2015-05-20 James P. Reed , Bruno Uchoa , Young Il Joe , Yu Gan , Diego Casa , Eduardo Fradkin , Peter Abbamonte

In a previous work, the meaning of the Planck constant $h = \left( e^2 / 2 \alpha \right) \sqrt{\mu_0 / \epsilon_0}$, accomplished by solving Maxwell's electrodynamics laws with specific electric $1 / \tau_C = 1 / R_q C_q$ and magnetic $1/…

General Physics · Physics 2023-03-02 Paulo Roberto Bueno

The fine structure of the neutral exciton in a single self assembled InGaAs quantum dot is investigated under the effect of a lateral electric field. Stark shifts up to 1.5 meV, an increase in linewidth, and a decrease in photoluminescence…

Mesoscale and Nanoscale Physics · Physics 2009-11-11 B. D. Gerardot , S. Seidl , P. A. Dalgarno , R. J. Warburton , D. Granados , J. M. Garcia , K. Kowalik , O. Krebs , K. Karrai , A. Badolato , P. M. Petroff

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.

It has been pointed out by Shlyakhter that data from the natural fission reactors which operated about two billion years ago at Oklo (Gabon) had the potential of providing an extremely tight bound on the variability of the fine-structure…

High Energy Physics - Phenomenology · Physics 2016-09-06 Thibault Damour , Freeman Dyson

The precision measurements of the ratio of hyperfine structure constants for $s_{1/2}$ and $p_{1/2}$ states allow us to estimate the difference between hyperfine magnetic anomalies for these levels. We calculate the atomic factor in order…

Atomic Physics · Physics 2020-12-02 E. A. Konovalova , Yu. A. Demidov , M. G. Kozlov

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

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

The argon spectral function is constructed and applied to neutrino-argon cross section computations in the plane wave impulse approximation with the Pauli blocking final state interaction effect taken into account. The approximations of the…

Nuclear Theory · Physics 2007-05-23 Artur M. Ankowski , Jan T. Sobczyk

We study the fine-structure constant dependence of the rates of some selected radiative capture reactions within the framework of so-called Halo Effective Field Theory in order to assess the adequacy of some assumptions made on the Coulomb…

Nuclear Theory · Physics 2024-10-17 Ulf-G. Meißner , Bernard Ch. Metsch , Helen Meyer

We put bounds on the variation of the value of the fine structure constant $\alpha$, at the time of Big Bang nucleosynthesis. We study carefully all light elements up to $^7$Li. We correct a previous upper limit on $|\Delta \alpha /…

Astrophysics · Physics 2009-10-31 L. Bergstrom , S. Iguri , H. Rubinstein

Light traveling through the vacuum interacts with vacuum fluctuations similarly to the way that light traveling through a dielectric interacts with ordinary matter. And just as the permittivity of a dielectric can be calculated, the…

General Physics · Physics 2026-02-17 G. B. Mainland , Bernard Mulligan
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