Collisions of excited Ps with antiprotons: Ps break-up and antihydrogen formation

Low energy antimatter science has reached an important stage: experiment has moved from being technique-limited and has reached

a point at which outputs can impact beyond a narrow discipline interest group.

In assessing feasibility, and influencing design to maximize the antihydrogen yields, theoretical studies

of collisions involving Ps is of a key importance. However, to date, a sufficiently detailed treatment

is only available for a few states. In the present work we exploit convergent close-coupling method

and the classical CTMC method in a broad range of principal and angular momentum quantum numbers. Convergent close-coupling

method is used for relatively low principal quantum number n, but as n grows, classical CTMC method becomes

more reliable.