Relativistic transition wavelenghts and probabilities for spectral lines of Ne II

Santos, J. P.; Costa, Ana Maria Medeiros da; Madruga, C.; Parente, F.; Indelicato, P.

doi:10.1140/epjd/e2011-10715-2

Cited by 35 publications

(65 citation statements)

References 46 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…From the general requirement of gauge invariance, the final results must be independent of G. The gauge invariance of the two-photon relativistic calculations was studied by Goldman and Drake [7], Santos et al [6], and Amaro et al [8].…”

Section: Relativistic Formulationmentioning

confidence: 99%

“…This calculation involves an infinite number of intermediate virtual states. However, excellent results can be obtained with a finite number of pseudostates, built on complete basis sets such as Dirac Green's functions [7], B splines [6], B polynomials [8], and Sturmians [9]. This calculation is simplified by the Lagrange-mesh method, which is an approximate variational method involving a basis of Lagrange functions related to a set of mesh points associated with a Gauss quadrature [10][11][12].…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Relativistic two-photon decay rates with the Lagrange-mesh method

2016

View full text Add to dashboard Cite

Relativistic two-photon decay rates of the 2s 1/2 and 2p 1/2 states towards the 1s 1/2 ground state of hydrogenic atoms are calculated by using numerically exact energies and wave functions obtained from the Dirac equation with the Lagrange-mesh method. This approach is an approximate variational method taking the form of equations on a grid because of the use of a Gauss quadrature approximation. Highly accurate values are obtained by a simple calculation involving different meshes for the initial, final, and intermediate wave functions and for the calculation of matrix elements. The accuracy of the results with a Coulomb potential is improved by several orders of magnitude in comparison with benchmark values from the literature. The general requirement of gauge invariance is also successfully tested, down to rounding errors. The method provides high accuracies for two-photon decay rates of a particle in other potentials and is applied to a hydrogen atom embedded in a Debye plasma simulated by a Yukawa potential.

show abstract

Section: Relativistic Formulationmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Relativistic two-photon decay rates with the Lagrange-mesh method

2016

View full text Add to dashboard Cite

show abstract

“…Bhatti and coworkers [16] used similar techniques to find an approximate solution of a set of the nonhomogeneous second-order differential equations and to obtain static polarizabilities of hydrogenic states. Indelicato and co-workers employed B-splines in the multiconfiguration Dirac-Fock (MCDF) relativistic atomic structure calculations [17,18] and in relativistic two-photon decay calculations [4,19,20].…”

Section: Introductionmentioning

confidence: 99%

Calculation of two-photon decay rates of hydrogen-like ions by using B-polynomials

Amaro

Surzhykov

Parente

et al. 2011

J. Phys. A: Math. Theor.

View full text Add to dashboard Cite

Abstract.A new approach is laid out to investigate the two-photon atomic transitions. It is based on application of the finite basis solutions constructed from the Bernstein Polynomial (B-Polynomial) sets. We show that such an approach provides a very promising route for the relativistic second-(and even higher-order) calculations since it allows for analytical evaluation of the involved matrices elements. In order to illustrate possible applications of the method and to verify its accuracy, detailed calculations are performed for the 2s 1/2 → 1s 1/2 transition in neutral hydrogen and hydrogen-like ions, and are compared with the theoretical predictions based on the well-established B-spline-basis-set approach.

show abstract

“…All electric dipole (E1), magnetic dipole (M1), electric quadrupole (E2), magnetic quadrupole (M2), electric octopole (E3), and magnetic octopole (M3) transitions among the 36 levels are taken into account in the lifetime calculation. As shown in Chen et al (2010), the E1 transitions predominate the lifetime, except for 2s 1/2 , for which the two-photon transition rates (Drake 1986;Santos et al 1998) should be considered. The detailed E1, M1, E2, M2, E3, and M3 transition rates (A r ) are listed in Table 2, together with the corresponding wavelengths (λ), absorption oscillator strengths ( f ), and line strengths (S ).…”

Section: Calculation Procedures and Resultsmentioning

confidence: 92%

Radiative rates and electron-impact excitation for then≤ 6 fine-structure levels in H-like ions with 13 ≤Z≤ 42

Yan

et al. 2015

A&A

View full text Add to dashboard Cite

Context. Many observed emission lines from space missions are due to highly charged H-like ions. An analysis of the lines provides information on the temperature, density, and chemical composition of plasmas. A wide range of atomic parameters, such as energy levels, radiative rates, and excitation rate coefficients are needed to achieve this goal. Aims. In this paper we report on calculations for energy levels, radiative rates, collision strengths, and effective collision strengths for transitions among the 36 lowest levels of the n ≤ 6 configurations of highly charged H-like ions with 13 ≤ Z ≤ 42. Methods. The widely used Flexible Atomic Code (FAC) is adopted for the calculation. Energy levels and radiative rates are calculated within the relativistic configuration-interaction method. Employing relativistic distorted-wave approximation, direct excitation collision strengths are calculated at eleven scattered electron energies E f = 0.001, 0.002, 0.005, 0.01, 0.02, 0.05, 0.1, 0.2, 0.5, 1.0, and 2.5, where E f is in units of Z 2 rydbergs. Collision strengths at higher energies are estimated by interpolation/extrapolation using relativistic Bethe form. Resonance contributions through the relevant He-like doubly excited n l n l configurations with n ≤ 7 and n ≤ 75 are explicitly taken into account using the independent-process isolated-resonance approximation. Radiation damping effects are taken into account. Results. We present the radiative rates, oscillator strengths, and line strengths for all electric dipole (E1), magnetic dipole (M1), electric quadrupole (E2), magnetic quadrupole (M2), electric octupole (E3), and magnetic octupole (M3) transitions. Assuming a Maxwellian electron velocity distribution, we report effective collision strengths over a wide temperature range between 2 × 10 3 × Z 2 and 2 × 10 6 × Z 2 K. We believe that the present results are the most extensive and definitive atomic dataset to date for highly charged H-like ions.

show abstract

Relativistic transition wavelenghts and probabilities for spectral lines of Ne II

Cited by 35 publications

References 46 publications

Relativistic two-photon decay rates with the Lagrange-mesh method

Relativistic two-photon decay rates with the Lagrange-mesh method

Calculation of two-photon decay rates of hydrogen-like ions by using B-polynomials

Radiative rates and electron-impact excitation for then≤ 6 fine-structure levels in H-like ions with 13 ≤Z≤ 42

Contact Info

Product

Resources

About