Étude par diagonalisation des taux de transition quantiques des états singulets et triplets de parité impaire 1,3Lo (L = 1, 2) dans les systèmes héliumoïdes Z = 6

Oumar NDIAYE

Résumé


Dans cet article, nous étudions la competition entre les états singulets et triplets des configurations 1,3Po et 1,3Do. Nous avons appliqué la méthode de diagonalisation au système héliumoïde de numéro atomique Z = 6, en dessous du seuil N = 4 convergeant vers l’ion résiduel. Grâce à cette méthode, nous avons pu identifier l’ensemble des transitions quantiques possibles. En calculant, d'une part, les énergies d'excitation (Eex) et d'autoionisation (Eau) et d'autre part, largeurs partielles et totales d'autoionisation. Nous avons mis en évidence les défis posés par la competition entre les états singulets et triplets des deux symmetries impaires. Cette approche est nouvelle et contribue à : (i) la prédiction et l’interprétation des signatures spectrales des ions héliumoïde en expérimentation, facilitant ainsi la comparaison entre théorie et observation ; et (ii) la modélisation des processus radiatifs et collisionnels dans les environnements plasmatiques, essentielle à la compréhension de leur composition et de leur dynamique.


Mots-clés


Diagonalisation ; systèmes héliumoïdes; 1,3Po ; 1,3Do; Photoionisation

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Références


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