# Electron-Impact Excitation of 51S – 51Po Resonance Transition in Sr Atom

### Abstract

Main aspects of a new version of the *B*-spline *R*-matrix (BSR) method, in which nonorthogonal orbitals are applied, have been described. The BSR approximation is used to calculate the resonance structure of integral cross-sections of the 5^{1}*S* - 5^{1}*P ^{o}* transition at the electron scattering by a strontium atom in the energy interval up to 10 eV. The multiconfiguration Hartree–Fock method with a nonorthogonal set of orbitals is employed to accurately represent the target wave functions. The close-coupling expansion included 31 bound states of a neutral strontium atom ranging from the ground state to the 5

*s*5

*f*

^{1}

*F*one. The calculated cross-sections are in good agreement with available experimental data and can be exhaustively interpreted. The structure of a resonance feature in the

^{o}*e*-Sr scattering cross-sections at about 4 eV is discussed.

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*Ukrainian Journal Of Physics, 63*(1), 11-24. Retrieved from https://ujp.bitp.kiev.ua/index.php/ujp/article/view/2018037/12

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