Time-Dependent Density-Functional Theory for Determining the Electron-Capture Cross Section for Protons Impacting on...

Area of Science:

• Atomic and Molecular Physics
• Computational Chemistry
• Plasma Physics

Background:

• Time-Dependent Density-Functional Theory (TDDFT) is increasingly used in atomic collision research.
• Electron-Capture Cross Section (ECCS) calculations for protons are vital for hadrontherapy and plasma physics.
• Previous studies indicated limitations of the Local Density Approximation (LDA) for ECCS in the 1-50 keV range, necessitating the Optimized Effective Potential (OEP) method.

Purpose of the Study:

• To determine ECCS values for 1-50 keV protons impacting hydrogen, carbon, nitrogen, oxygen, and nitrogenous atoms using TDDFT.
• To evaluate the effectiveness of the Self-Interaction Correction to LDA (LDA-Sic) as an alternative to OEP.
• To investigate the necessity of spin correction for specific atomic targets.

Main Methods:

• Utilized Time-Dependent Density-Functional Theory (TDDFT) for calculations.
• Employed the Local Density Approximation with Self-Interaction Correction (LDA-Sic).
• Investigated the impact of spin correction on ECCS for helium and oxygen.

Main Results:

• LDA-Sic yielded ECCS results comparable to OEP and experimental values for protons impacting various atoms.
• LDA-Sic demonstrated a significant reduction in computational time compared to OEP.
• Spin correction was found to be essential for accurate ECCS in helium and oxygen calculations.
• Theoretical results showed excellent agreement with experimental data.

Conclusions:

• LDA-Sic offers an efficient and accurate method for calculating ECCS for protons within the 1-50 keV energy range.
• The inclusion of spin correction is critical for specific atomic targets like helium and oxygen.
• TDDFT, particularly with LDA-Sic, provides a reliable theoretical framework for ECCS relevant to hadrontherapy and plasma physics.