scholarly journals 6Pe—6Po transitions in boron-like ions with Z = 8–13

2016 ◽  
Vol 94 (3) ◽  
pp. 283-289 ◽  
Author(s):  
Jian Zhang ◽  
Yan Sun ◽  
Cui Cui Sang ◽  
Shuo Yan ◽  
Wen Yi Li ◽  
...  
Keyword(s):  
Quantum Electrodynamics ◽  
Theoretical Data ◽  
Spectral Lines ◽  
Variation Method ◽  
Transition Rates ◽  
Isoelectronic Sequence ◽  
First Order ◽  
Relativistic Corrections ◽  
Qed Effects ◽  
Nuclear Charge Number

The energies, fine structure splittings, transition rates, and lifetimes of inner-shell excited sextet states 1s2s2p2nl, (n = 2–7; l = s, p, d) and 1s2p33p of the boron isoelectronic sequence (Z = 8–13) are investigated using the multi-configuration Rayleigh–Ritz variation method. The mass polarization effect and relativistic corrections are included by first-order perturbation theory. Configuration structures of the high-n inner-shell excited sextet series 6Se,o(m) and 6Pe,o(m) (m = 1–5) of boron-like Na6+ ion are assigned. The wavelengths and transition rates of electric-dipole transitions between 6Pe(m) and 6Po(m) (m = 1–5) states are calculated. The quantum electrodynamics (QED) effects and higher order relativistic corrections are also considered to obtain more accurate transition wavelengths. The predicted transition wavelengths agree well with the available theoretical and experimental data. The lifetimes for the inner-shell excited sextet states 6Pe(m) (m = 1–5) are also reported and discussed with the increase of nuclear charge number, Z. These theoretical data are useful for the identification of spectral lines in experiments and the design of XUV and soft X-ray lasers.

Energies, wavelengths, lifetimes, E1, M1, E2, and M2 transitions rates for the sulfur isoelectronic sequence Fe XI, Nb XXVI–In XXXIV

2017 ◽  
Vol 95 (4) ◽  
pp. 393-401 ◽  
Author(s):  
K. Wang ◽  
S. Li ◽  
R. Si ◽  
C.Y. Chen ◽  
J. Yan ◽  
...  
Keyword(s):  
Quantum Electrodynamics ◽  
Energy Levels ◽  
Theoretical Data ◽  
Electric Quadrupole ◽  
Oscillator Strengths ◽  
Transition Rates ◽  
Isoelectronic Sequence ◽  
Fusion Plasma ◽  
Magnetic Quadrupole ◽  
Theoretical Results

Energies, wavelengths, lifetimes, oscillator strengths, electric dipole (E1), electric quadrupole (E2), magnetic dipole (M1), and magnetic quadrupole (M2) transition rates among the 42 fine structure levels belonging to the 3s23p4, 3s23p33d, and 3s3p5 configurations for S-like Fe and S-like ions with 41 ≤ Z ≤ 49 are calculated using the fully relativistic multiconfiguration Dirac–Fock (MCDF) method. In the calculations, contributions from correlations within the n = 6 complex, Breit interaction, and quantum electrodynamics effects are included. Detailed comparisons are made between the present results and the available experimental and other theoretical data. We found that our calculated energy levels generally agree within ≤0.5% with the experimentally compiled results, and the transition rates agree within ≤12% with other theoretical results for a majority of the transitions. These accurate theoretical data should be beneficial in fusion plasma research and astrophysical applications.

RELATIVISTIC ENERGY, OSCILLATOR STRENGTHS AND TRANSITION RATES OF THE 1s2 2 ln l 1S(m)(n =2–6, m1–5) STATES FOR Be-LIKE SYSTEM

2005 ◽  
Vol 16 (06) ◽  
pp. 951-968 ◽  
Author(s):  
MENG ZHANG ◽  
BING-CONG GOU
Keyword(s):  
Experimental Data ◽  
Energy Levels ◽  
Oscillator Strengths ◽  
Relativistic Energy ◽  
Transition Rates ◽  
Isoelectronic Sequence ◽  
Polarization Effects ◽  
First Order ◽  
Variational Calculations ◽  
First Order Perturbation

Variational calculations are carried out with a multiconfiguration-interaction wave function to obtain the relativistic energies of the 1s2 2 ln l 1 S (m)(n =2–6, m1–5) states for the beryllium isoelectronic sequence (Z =4–10). Relativistic corrections and the mass polarization effects are evaluated with the first-order perturbation theory. The identifications of the energy levels for 1s2 2 ln l 1 S (m)(n =2–6, m1–5) states in the Be-like ions are reported. The oscillator strengths, transition rates and wavelengths are also calculated. The calculated results are compared with other theoretical and experimental data in the literature.

Energies and hyperfine structures of the 1s22s2p 3Po state of Be-like ions with Z = 11–18

2017 ◽  
Vol 95 (8) ◽  
pp. 720-724 ◽  
Author(s):  
Kai Kai Li ◽  
Lin Zhuo ◽  
Chun Mei Zhang ◽  
Chao Chen ◽  
Bing Cong Gou
Keyword(s):  
Hyperfine Coupling ◽  
Reference Data ◽  
Correlation Method ◽  
Theoretical Data ◽  
Coupling Constants ◽  
Isoelectronic Sequence ◽  
Excitation Energies ◽  
First Order ◽  
Hyperfine Structures ◽  
Good Agreement

Nonrelativistic energies and wave functions of the 1s22s2p 3Po states of Be isoelectronic sequence (Z = 11–18) are calculated using the full core plus correlation method (FCPC). To obtain the accurate energy level, the relativistic corrections and mass polarization effect are included by using the first-order perturbation theory. The calculated excitation energies (relative to the 1s22s2 ground state) are compared with the experiment. Most of the calculated [Formula: see text] energies agree with the experiment to within a few inverse centimetres. The calculated hyperfine coupling constants are in good agreement with the latest theoretical data in the literature. Our results may provide valuable reference data for spectral analysis and identification in the future.

scholarly journals Calculations of QED Effects with the Dirac Green Function

Symmetry ◽  
2020 ◽  
Vol 12 (5) ◽  
pp. 800 ◽  
Author(s):  
Vladimir A. Yerokhin ◽  
Anna V. Maiorova
Keyword(s):  
Green Function ◽  
Quantum Electrodynamics ◽  
Nuclear Charge ◽  
Structure Constant ◽  
Fine Structure Constant ◽  
Strength Parameter ◽  
Theoretical Treatment ◽  
Binding Strength ◽  
Qed Effects ◽  
Nuclear Charge Number

Modern spectroscopic experiments in few-electron atoms reached the level of precision at which an accurate description of quantum electrodynamics (QED) effects is mandatory. In many cases, theoretical treatment of QED effects need to be performed without any expansion in the nuclear binding strength parameter Z α (where Z is the nuclear charge number and α is the fine-structure constant). Such calculations involve multiple summations over the whole spectrum of the Dirac equation in the presence of the binding nuclear field, which can be evaluated in terms of the Dirac Green function. In this paper we describe the technique of numerical calculations of QED corrections with the Dirac Green function, developed in numerous investigations during the last two decades.

scholarly journals Energy, fine structure, hyperfine structure, and transitions for the high-lying multi-excited 4Pe,o states of B-like ions

2016 ◽  
Vol 94 (5) ◽  
pp. 448-457
Author(s):  
Chun Mei Zhang ◽  
Yan Sun ◽  
Chao Chen ◽  
Feng Wang ◽  
Bin Shao ◽  
...  
Keyword(s):  
Perturbation Theory ◽  
Fine Structure ◽  
Hyperfine Structure ◽  
Excited States ◽  
Quantum Electrodynamic ◽  
Higher Order ◽  
Variation Method ◽  
First Order ◽  
Relativistic Corrections ◽  
First Order Perturbation

The energies of the high-lying multi-excited states 1s22s2pnl and 1s22p2nl 4Pe,o (n ≥ 2) for B-like C+, N2+, F4+, and Mg7+ ions are calculated using Rayleigh–Ritz variation method with multiconfiguration interaction, and the inclusion of mass polarization and relativistic corrections. The fine structure and hyperfine structure for these systems are investigated using first-order perturbation theory. The configuration structure of the high-lying multi-excited series is identified not only by energy, but also by its contribution to normalization of the angular spin components, and it is further tested by the addition of relativistic corrections and fine structure splittings. Transition wavelengths including the quantum electrodynamic effects and higher-order relativistic corrections are determined.

ENERGY, OSCILLATOR STRENGTH AND HYPERFINE STRUCTURE OF THE LOW-LYING EXCITED STATES FOR Be-LIKE SYSTEM

2003 ◽  
Vol 14 (05) ◽  
pp. 549-560 ◽  
Author(s):  
FEI WANG ◽  
BINGCONG GOU ◽  
XIAOLI WU ◽  
LIHONG HAN
Keyword(s):  
Experimental Data ◽  
Wave Function ◽  
Variational Method ◽  
Hyperfine Structure ◽  
Oscillator Strength ◽  
Excited States ◽  
Oscillator Strengths ◽  
Transition Rates ◽  
Isoelectronic Sequence ◽  
Relativistic Corrections

The Rayleigh–Ritz variational method is carried out with a multiconfiguration-interaction wave function and restricted variational method to obtain the relativistic energies of the 1s22s2p 1Po , 1s22s2p 3Po , and 1s22p23P states for the beryllium-like isoelectronic sequence (Z=4–10), including the mass polarization and relativistic corrections. The oscillator strengths and transition rates are also calculated. The results are compared with other theoretical and experimental data in the literature. The hyperfine structure of the low-lying excited states for this system is also explored.

Photocolouration of 2,4,4,6-Tetraaryl-4H-pyrans and Their Heteroanalogues: Importance of Hypervalent Photoisomers

1995 ◽  
Vol 60 (10) ◽  
pp. 1621-1633 ◽  
Author(s):  
Stanislav Böhm ◽  
Mojmír Adamec ◽  
Stanislav Nešpůrek ◽  
Josef Kuthan
Keyword(s):  
Reaction Kinetics ◽  
Absorption Spectra ◽  
Electronic Absorption ◽  
Electronic Absorption Spectra ◽  
Theoretical Data ◽  
Order Reaction ◽  
Bleaching Process ◽  
First Order ◽  
Photodegradation Products ◽  
Hypervalent Molecules

Molecular geometries of 2,4,4,6-tetraphenyl-4H-pyran (Ia), 4,4-(biphenyl-2,2e-diyl)-2,6-diphenyl-4H-pyran (Ib) and their heterocyclic isomers II-V were optimized by the PM3 method and used for the calculation of electronic absorption spectra by the CNDO/S-CI procedure. Comparison of the theoretical data with experimental UV-VIS absorption spectra made possible to select hypervalent molecules IIIa, IIIb, IVa and IVb being responsible for the photocolouration of 4H-pyrans Ia, Ib, while compounds Va, Vb, VI and VII come into account as possible photodegradation products. The bleaching process of the UV illuminated compound Ia is analyzed in terms of dispersive first-order reaction kinetics.

scholarly journals Measured Stark widths and shifts in the O IV spectrum

2003 ◽  
pp. 51-54 ◽  
Author(s):  
Stevan Djenize ◽  
Aleksandar Sreckovic ◽  
Srdjan Bukvic ◽  
Slobodanka Kalezic
Keyword(s):  
Arc Discharge ◽  
Theoretical Data ◽  
Plasma Source ◽  
Spectral Lines ◽  
Pulsed Arc Discharge ◽  
D Values ◽  
And Shifts ◽  
Pulsed Arc ◽  
Good Agreement ◽  
Thin Plasma

Stark widths (W) and shifts (d) of 5 prominent triply ionized oxygen (O IV) spectral lines in 3 multiplets have been measured in oxygen plasma at 42 000 K electron temperature using a linear, low-pressure, pulsed arc discharge as an optically thin plasma source. Obtained W and d values have been compared to available experimental and theoretical data. We found a good agreement among our experimental W and d values and theoretical expectations.

scholarly journals Light-cone distribution amplitudes of light mesons with QED effects

2021 ◽  
Vol 2021 (11) ◽  
Author(s):  
Martin Beneke ◽  
Philipp Böer ◽  
Jan-Niklas Toelstede ◽  
K. Keri Vos
Keyword(s):  
Light Cone ◽  
Electromagnetic Coupling ◽  
First Order ◽  
Order Expansion ◽  
Group Evolution ◽  
Fixed Order ◽  
Light Mesons ◽  
Charged Mesons ◽  
Qed Effects ◽  
Exclusive Processes

Abstract We discuss the generalization of the leading-twist light-cone distribution amplitude for light mesons including QED effects. This generalization was introduced to describe virtual collinear photon exchanges at the strong-interaction scale ΛQCD in the factorization of QED effects in non-leptonic B-meson decays. In this paper we study the renormalization group evolution of this non-perturbative function. For charged mesons, in particular, this exhibits qualitative differences with respect to the well-known scale evolution in QCD only, especially regarding the endpoint-behaviour. We analytically solve the evolution equation to first order in the electromagnetic coupling αem, which resums large logarithms in QCD on top of a fixed-order expansion in αem. We further provide numerical estimates for QED corrections to Gegenbauer coefficients as well as inverse moments relevant to (QED-generalized) factorization theorems for hard exclusive processes.

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