Time-dependent close-coupling calculations of dielectronic capture in He

Area of Science:

• Atomic Physics
• Quantum Mechanics
• Computational Chemistry

Background:

• Dielectronic capture is a key process in atomic physics, influencing plasma spectroscopy and electron-ion interactions.
• Understanding doubly excited states is crucial for accurately modeling atomic processes.
• Previous calculations often lacked the time-dependent resolution to capture the full dynamics.

Purpose of the Study:

• To perform the first time-dependent close-coupling calculation for dielectronic capture into doubly excited states.
• To investigate the dynamics of electron wave packet collisions with helium ions.
• To determine capture probabilities and subsequent autoionization rates.

Main Methods:

• Utilizing a time-dependent close-coupling approach.
• Representing the incoming electron as a Gaussian wave packet.
• Solving the close-coupling equations on a two-dimensional radial lattice.
• Projecting the wave function onto doubly excited states of neutral helium.

Main Results:

• Successfully calculated the time-dependent dielectronic capture process.
• Determined the probability amplitude for capture into specific doubly excited states.
• Quantified the subsequent autoionization from these states.

Conclusions:

• The developed method provides a robust framework for studying time-dependent electron-atom interactions.
• This work advances the understanding of dielectronic capture dynamics in two-electron systems.
• The results are vital for accurate atomic data in various applications.