arXiv subjects

S. Boucard

Publications and source records attributed to S. Boucard.

3 recordsLinked to original sources

arXiv2007

QED and relativistic corrections in superheavy elements

In this paper we review the different relativistic and QED contributions to energies, ionic radii, transition probabilities and Landé $g$-factors in super-heavy elements, with the help of the MultiConfiguration Dirac-Fock method (MCDF). The effects of taking into account the Breit interaction to all orders by including it in the self-consistent field process are demonstrated. State of the art radiative corrections are included in the calculation and discussed. We also study the non-relativistic limit of MCDF calculation and find that the non-relativistic offset can be unexpectedly large.

physics.atom-ph↗

arXiv2006

Highly charged ion X-rays from Electron-Cyclotron Resonance Ion Sources

Radiation from the highly-charged ions contained in the plasma of Electron-Cyclotron Resonance Ion Sources constitutes a very bright source of X-rays. Because the ions have a relatively low kinetic energy ($\approx 1$ eV) transitions can be very narrow, containing only small Doppler broadening. We describe preliminary accurate measurements of two and three-electron ions with Z=16--18. We show how these measurement can test sensitively many-body relativistic calculations or can be used as X-ray standards for precise measurements of X-ray transitions in exotic atoms.

physics.atom-ph↗

arXiv2004

X-ray energies of circular transitions and electrons screening in kaonic atoms

The QED contribution to the energies of the circular (n,l=n-1), 2 ≤ n ≤ 19 transitions have been calculated for several kaonic atoms throughout the periodic table, using the current world average kaon mass. Calculations were done in the framework of the Klein-Gordon equation, with finite nuclear size and all-order Uelhing vacuum polarization corrections, as well as Kallen and Sabry and Wichmann and Kroll corrections. These energy level values are compared with other computed values. The circular transition energies are compared with available measured and theoretical transition energy. Electron screening is evaluated using a Dirac-Fock model for the electronic part of the wave function. The effect of electronic wavefunction correlation is evaluated for the first time.

physics.atom-ph↗