scholarly journals The g factor in a light two-body atomic system: a determination of fundamental constants to test QED

2002 ◽  
Vol 80 (11) ◽  
pp. 1305-1312 ◽  
Author(s):  
S G Karshenboim ◽  
V G Ivanov
Keyword(s):  
Atomic System ◽  
Magnetic Moments ◽  
Energy Levels ◽  
Homogeneous Magnetic Field ◽  
Fundamental Constants ◽  
Atomic Systems ◽  
System A ◽  
New Generation ◽  
G Factors

The energy levels of a two-body atomic system in an external homogeneous magnetic field can be presented in terms of the magnetic moments of their components, however, those magnetic moments being related to bound particles differ from their free values. The study of bound g-factors in simple atomic systems are now of interest because of recent progress in experiments on medium-Z ions and of a new generation of muonium experiments possible with upcoming intensive muon sources. We consider bound corrections to the g factors in several atomic systems, for which experimental data are available in the literature: hydrogen, helium-3 ion, muonium, hydrogen-like ions with spinless nuclei with medium Z. PACS Nos.: 12.20Fv, 31.30Jv, 32.10Hq

Influence of Hygrothermal Environmental Conditions on the Vibratory Responses of Glass Polyester Composite Plate Impacted by a Steel Projectile

2017 ◽  
Vol 28 ◽  
pp. 8-20
Author(s):  
Amine Bakhti ◽  
Farouk Benallel Boukhoulda
Keyword(s):  
Contact Force ◽  
Energy Levels ◽  
Composite Plates ◽  
Mechanical Responses ◽  
System A ◽  
Resonance Frequencies ◽  
Polyester Composite ◽  
The Impact ◽  
Aged Composite

The objective of the present work is an analysis of vibratory responses due to the impact of projectile in steel against a glass/polyester composite material under hygrothermal conditions with different energy levels. In the first part of this study, by means of a data acquisition system, a signal processing analysis of the contact force and acceleration of the projectile is carried out in order to deduce the oscillations of the responses. These are generated by the vibrations induced by the contact between the plate and the impactor. The analysis of the vibrations by the calculation of the Fast Fourier Transform (FFT) applied to the oscillations of the contact force allows to defining the resonance frequencies of the plate for the different energy levels. The measure of the Frequency Response Functions (FRF) from the obtained responses allows the determination of the damping of the impacted composite material.In the second part of this study highlights quantitatively and puts into evidence the influence of hygrothermal conditions on the mechanical responses such as contact force, acceleration, frequency and damping of aged and non-aged composite plates.

scholarly journals Two-body corrections to the g factors of the bound muon and nucleus in light muonic atoms

2019 ◽  
Vol 73 (10) ◽  
Author(s):  
Savely G. Karshenboim ◽  
Vladimir G. Ivanov
Keyword(s):  
Electrostatic Interaction ◽  
Coulomb Potential ◽  
Atomic System ◽  
Magnetic Moments ◽  
Master Equations ◽  
Atomic Systems ◽  
Muonic Atoms ◽  
Pure Coulomb ◽  
Coulomb Effects ◽  
Three Body

Abstract A nonrelativistic (NR) theory of recoil corrections to the magnetic moments of bound particles is revisited. A number of contributions can be described within an NR theory with the help of various potentials. We study those potential-type contributions for two-body atomic systems. We have developed an approach, that allows us to find the g factor for an electron or muon in a two-body bound system for an arbitrary electrostatic interaction together with the m/M recoil corrections, as well as the binding corrections to the g factor of the nucleus. We focus our attention on light muonic two-body atoms, where the recoil effects are enhanced. Both mentioned kinds of contributions have been previously known only for the pure Coulomb effects. We have applied the here-obtained master equations to a few particular cases of perturbations of the Coulomb potential. In particular, the results on the recoil corrections to the finite-nuclear-size (FNS) and Uehling-potential contributions to the g factor of the bound muon are obtained. The Uehling-potential and FNS contributions to the g factor of the bound nucleus have been found as well together with the related recoil corrections. We have generalized the results for the case of the g factor of a bound muon in a three-body atomic system consisting of an electron, a muon, and a spinless nucleus. Graphical abstract

The Calculations for Determination of the Age of Supernova Remnants and Galaxy Clusters by Measurements of Hyperfine Splitting in Highly ionized Atoms with Unstable Nuclei

1988 ◽  
Vol 102 ◽  
pp. 127
Author(s):  
I.M. Band ◽  
M.A. Listengarten ◽  
M.B. Trzhaskovskaya
Keyword(s):  
Galaxy Clusters ◽  
Supernova Remnants ◽  
Nuclear Charge ◽  
Magnetic Moments ◽  
Energy Levels ◽  
Hartree Fock ◽  
Hot Gas ◽  
Unstable Nuclei ◽  
Vacuum Polarisation

The possibility of using the transitions between HFS components of atoms with nonstable nuclei in the spectra of hot gas in the supernova remnants and galaxy clusters for obtaining the information on the age of the objects was mentioned in /l/ without calculations. Here we present the numerical results for some ionized atoms obtained by relastivistic Hartree-Fock-Dirac method. Fermi distribution of nuclear charge density, vacuum polarisation, electron anomalous magnetic moment and reduced mass were taken into account. The HFS energy levels can be written aswhere A=A’(μ/J). HFS constants A’ in millielectronvolts for H- Li- and Na-like ions of unstable isotops with well known magnetic moments with Z < 53 are given in the table (abundance rapidly decreases with increasing of Z). For the s-electrons, wavelength λ = (hcJ)/(Aμ(J+(1/2))); J is the nuclear spin, hc= 1,23985.10−4eV.cm T1/2is the halflife.

scholarly journals Electromagnetic corrections to the hadronic vacuum polarization of the photon within QEDL and QEDM

2018 ◽  
Vol 175 ◽  
pp. 06005 ◽  
Author(s):  
Andrea Bussone ◽  
Michele Della Morte ◽  
Tadeusz Janowski
Keyword(s):  
Dispersion Relation ◽  
Finite Volume ◽  
Vacuum Polarization ◽  
Magnetic Moments ◽  
Energy Levels ◽  
Percent Level ◽  
Wilson Loops ◽  
Zero Modes ◽  
Charged Pions

We compute the leading QED corrections to the hadronic vacuum polarization (HVP) of the photon, relevant for the determination of leptonic anomalous magnetic moments, al. We work in the electroquenched approximation and use dynamical QCD configurations generated by the CLS initiative with two degenerate flavors of nonperturbatively O(a)-improved Wilson fermions. We consider QEDL and QEDM to deal with the finite-volume zero modes. We compare results for the Wilson loops with exact analytical determinations. In addition we make sure that the volumes and photon masses used in QEDM are such that the correct dispersion relation is reproduced by the energy levels extracted from the charged pions two-point functions. Finally we compare results for pion masses and the HVP between QEDL and QEDM. For the vacuum polarization, corrections with respect to the pure QCD case, at fixed pion masses, turn out to be at the percent level.

scholarly journals Quantitative Determination of the Effects of He-Ne Laser Irradiation on Seed Thermodynamics, Germination Attributes and Metabolites of Safflower (Carthamus tinctorius L.) in Relation with the Activities of Germination Enzymes

Agronomy ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1411
Author(s):  
Rashida Perveen ◽  
Xiukang Wang ◽  
Yasir Jamil ◽  
Qasim Ali ◽  
Shafaqat Ali ◽  
...  
Keyword(s):  
Seed Germination ◽  
Energy Levels ◽  
Soluble Sugars ◽  
Building Blocks ◽  
Carthamus Tinctorius ◽  
Fast Decline ◽  
Seed Irradiation ◽  
Seed Reserves ◽  
Positive Correlations

The present investigation was undertaken to assess the effects of different doses (100, 300, and 500 mJ) of low power He–Ne laser (632.8 nm) irradiation on seed germination and thermodynamics attributes and activities of potential germinating enzymes in relation with changes in seed metabolites. He–Ne laser seed irradiation increased the amylase (Amy), protease (Pro) and glucosidase (Gluco) activities, with a significant improvement in seed thermodynamics and seed germination attributes. A fast increase was found in free fatty acids (FFA), free amino acids (FAA), chlorophyll (Chl), carotenoids (Car), total soluble sugars (TSS) and reducing sugars (RS) in laser treated seeds in parallel with fast decline in seed oil contents and total soluble proteins (TSP). Significant positive correlations were recorded in laser-induced enhanced seed energy levels, germination, activities of germination enzymes with levels of FAA, FFA, Chl, TSS and RS, but a negative correlation with the levels of TSP and oil. In conclusion, the seed treatment with 100 and 300 mJ He–Ne laser was more effective to improve the seed germination potential associated with an improvement in seed energy levels due to increased activities of germination enzymes due to the speedy breakdown of seed reserves to simple metabolites as building blocks.

scholarly journals The Application of Electromagnetic Sensors for Determination of Cherenkov Cone Inside and in the Vicinity of the Detector Volume in Any Environment Known

Sensors ◽  
2021 ◽  
Vol 21 (3) ◽  
pp. 992
Author(s):  
Valeriu Savu ◽  
Mădălin Ion Rusu ◽  
Dan Savastru
Keyword(s):  
Energy Levels ◽  
Cherenkov Detector ◽  
Electromagnetic Sensors ◽  
The Cost ◽  
Information Errors ◽  
The Universe ◽  
Large Frequency ◽  
Very High ◽  
Detector Volume

The neutrinos of cosmic radiation, due to interaction with any known medium in which the Cherenkov detector is used, produce energy radiation phenomena in the form of a Cherenkov cone, in very large frequency spectrum. These neutrinos carry with them the information about the phenomena that produced them and by detecting the electromagnetic energies generated by the Cherenkov cone, we can find information about the phenomena that formed in the universe, at a much greater distance, than possibility of actually detection with current technologies. At present, a very high number of sensors for detection electromagnetic energy is required. Thus, some sensors may detect very low energy levels, which can lead to the erroneous determination of the Cherenkov cone, thus leading to information errors. As a novelty, we propose, to use these sensors for determination of the dielectrically permittivity of any known medium in which the Cherenkov detector is used, by preliminary measurements, the subsequent simulation of the data and the reconstruction of the Cherenkov cone, leading to a significant reduction of problems and minimizing the number of sensors, implicitly the cost reductions. At the same time, we offer the possibility of reconstructing the Cherenkov cone outside the detector volume.

Theoretical progress in the H2+ molecular ion: towards electron to proton mass ratio determinationThis paper was presented at the International Conference on Precision Physics of Simple Atomic Systems, held at École de Physique, les Houches, France, 30 May – 4 June, 2010.

2011 ◽  
Vol 89 (1) ◽  
pp. 103-107 ◽  
Author(s):  
J.-Ph. Karr ◽  
L. Hilico ◽  
V. I. Korobov
Keyword(s):  
High Resolution ◽  
Mass Ratio ◽  
Theoretical Determination ◽  
Atomic Systems ◽  
The Road ◽  
Theoretical Progress ◽  
Proton Mass ◽  
Accuracy Level ◽  
Ratio Determination

High resolution ro-vibrational spectroscopy of H 2+ or HD+ can lead to a significantly improved determination of the electron to proton mass ratio me/mp if the theoretical determination of transition frequencies becomes sufficiently accurate. We report on recent theoretical progress in the description of the hyperfine structure of H 2+ , as well as first steps in the evaluation of radiative corrections at order mα7. Completion of the latter calculation should allow us to reach the projected 10−10 accuracy level and open the road to mass ratio determination.

scholarly journals Semiclassical calculations of the quadruple excited four-electron systems

2007 ◽  
pp. 33-44
Author(s):  
N. Simonovic ◽  
M. Predojevic ◽  
V. Pankovic ◽  
P. Grujic
Keyword(s):  
Energy Levels ◽  
Point Of View ◽  
Interstellar Space ◽  
Vibrational Modes ◽  
Electron Systems ◽  
Atomic Systems ◽  
Excited Atoms ◽  
Relative Contribution ◽  
Quantum Numbers ◽  
Semiclassical States

Highly excited atoms acquire very large dimensions and can be present only in a very rarified gas medium, such as the interstellar space. Multiply excited beryllium-like systems, when excited to large principal quantum numbers, have a radius of r ? 10 ?. We examine the semiclassical spectrum of quadruple highly excited four-electron atomic systems for the plane model of equivalent electrons. The energy of the system consists of rotational and vibrational modes within the almost circular orbit approximation, as used in a previous calculation for the triply excited three-electron systems. Here we present numerical results for the beryllium atom. The lifetimes of the semiclassical states are estimated via the corresponding Lyapunov exponents. The vibrational modes relative contribution to the energy levels rises with the degree of the Coulombic excitation. The relevance of the results is discussed both from the observational and heuristic point of view.

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