Martins, M. C., J. P. Santos, A. M. Costa, and F. Parente. "
Transition wavelengths and probabilities for spectral lines of Zr III."
The European Physical Journal D 39 (2006): 167-172.
AbstractWavelengths and oscillator strengths for all dipole-allowed fine-structure transitions in Zr III have been calculated within the Multi-Configuration Dirac-Fock method with QED corrections. These transitions are included in the spectrum of some chemically peculiar stars, like the B-type star Lupi observed by the Hubble space telescope. The results are compared to existing experimental and semi-empirical data.
Santos, J. P., M. C. Martins, A. M. Costa, P. Indelicato, and F. Parente. "
X-ray spectra emitted by Cl14+ ions in ECRIS plasmas."
Vacuum 82 (2008): 1522-1524.
AbstractWe study the contribution of the most important processes leading to the creation of excited states of Cl14+ ions from the ground configurations of Cl ions in an Electron Cyclotron Resonance Ion Source (ECRIS), which lead to the emission of K X-ray lines. Theoretical values for inner-shell excitation, K and KL ionization cross-sections, and energies and transition probabilities for the de-excitation processes are calculated in the framework of the Multi-Configuration Dirac-Fock (MCDF) method. With reasonable assumptions about the electron energy distribution, a theoretical K[alpha] X-ray spectrum is obtained, which reproduces closely a recent experimental result.
Santos, J. P., A. M. Costa, J. P. Marques, M. C. Martins, P. Indelicato, and F. Parente. "
X-ray-spectroscopy analysis of electron-cyclotron-resonance ion-source plasmas."
Physical Review A 82 (2010): 062516.
AbstractAnalysis of x-ray spectra emitted by highly charged ions in an electron-cyclotron-resonance ion source (ECRIS) may be used as a tool to estimate the charge-state distribution (CSD) in the source plasma. For that purpose, knowledge of the electron energy distribution in the plasma, as well as the most important processes leading to the creation and de-excitation of ionic excited states are needed. In this work we present a method to estimate the ion CSD in an ECRIS through the analysis of the x-ray spectra emitted by the plasma. The method is applied to the analysis of a sulfur ECRIS plasma.