Doubly differential cross sections for ionization in <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msup><mml:mrow><mml:mi>He</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn><mml:mo>+</mml:mo></mml:mrow></mml:msup><mml:mo>+</mml:mo><mml:mi>He</mml:mi></mml:mrow></mml:math> collisions
Annotatsiya
We study the <a:math xmlns:a="http://www.w3.org/1998/Math/MathML"><a:mrow><a:mmultiscripts><a:mi>He</a:mi><a:none/><a:mrow><a:mn>2</a:mn><a:mo>+</a:mo></a:mrow><a:mprescripts/><a:none/><a:mn>3</a:mn></a:mmultiscripts><a:mo>+</a:mo><a:mi>He</a:mi></a:mrow></a:math> differential ionization problem using the two-electron wave-packet convergent close-coupling (WP-CCC) method. We present the results for doubly differential cross sections for ionization in terms of the angle and energy of the emitted electrons at intermediate collision energies. In this energy region, coupling between all reaction channels and electron-electron correlation effects are of considerable importance. These are fully accounted for in the WP-CCC approach. Overall, our results are in good agreement with the available experimental data and other theoretical calculations. We also discuss the saddle-point ionization mechanism for this collision system. It is concluded that this mechanism is not justified in the intermediate-energy region.