Electron-Impact Excitation of the <i>λ</i>190.8 nm and <i>λ</i>179.9 nm Intercombination Lines in the Tl<sup>+</sup> Ion

The results of experimental and theoretical studies on electron-impact excitation of the <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mn>6</mn><mi>s</mi><mn>6</mn>&l...

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Bibliographic Details
Main Authors: Anna Gomonai, Viktoria Roman, Aleksandr Gomonai, Aloka Kumar Sahoo, Lalita Sharma
Format: Article
Language:English
Published: MDPI AG 2022-11-01
Series:Atoms
Subjects:
Online Access:https://www.mdpi.com/2218-2004/10/4/136
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Summary:The results of experimental and theoretical studies on electron-impact excitation of the <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mn>6</mn><mi>s</mi><mn>6</mn><mi>p</mi><mo> </mo><mmultiscripts><mi>P</mi><mn>1</mn><mo>°</mo><mo> </mo><mn>3</mn></mmultiscripts><mo>→</mo><mn>6</mn><msup><mi>s</mi><mn>2</mn></msup><mo> </mo><mmultiscripts><mi>S</mi><mn>0</mn><mo> </mo><mn>1</mn><mrow></mrow></mmultiscripts></mrow></semantics></math></inline-formula> (<i>λ</i>190.8 nm) and <inline-formula><math xmlns="http://www.w3.org/1998/Math/MathML" display="inline"><semantics><mrow><mn>6</mn><mi>s</mi><mn>7</mn><mi>s</mi><mo> </mo><mmultiscripts><mi>S</mi><mn>0</mn><mo> </mo><mn>1</mn><mrow></mrow></mmultiscripts><mo>→</mo><mn>6</mn><mi>s</mi><mn>6</mn><mi>p</mi><mo> </mo><mmultiscripts><mi>P</mi><mn>1</mn><mo>°</mo><mo> </mo><mn>3</mn></mmultiscripts></mrow></semantics></math></inline-formula> (<i>λ</i>179.9 nm) intercombination transitions in the single-charged thallium ion are presented. The crossed-beams technique was used in combination with a spectroscopic method in the experiment. A distinct structure revealed in the cross-sections of both lines results from electron decay of atomic autoionizing states and radiative transitions from upper ionic levels. The dominant mechanism of the structure formation was the Coster–Kronig process. Relativistic distorted wave calculations were performed to obtain emission cross-sections for the above transitions. The absolute values of the cross-sections were found to be (0.25 ± 0.08) × 10<sup>−16</sup> cm<sup>2</sup> (<i>λ</i>190.8 nm) and (0.10 ± 0.04) × 10<sup>−16</sup> cm<sup>2</sup> (<i>λ</i>179.9 nm) at the electron energy of 100 eV.
ISSN:2218-2004