| Research Abstract |
1.A semiclassical close-coupling equation is formulated for the electron-captureprocess in ion-atom collisions under the influence of an external magnetic field where the field direction was arbitrary to the incident projectile velocity. This formula has been applied to some systems, i.e., (B^<4+>+H), (Be^<2+>+H), (Be^<3+>+H), and (He^<2+>+H). The main results obtained by these calculations are as follows.
(1) In general, the magnetic field make the electron capture accelerate, but for some states and/or at certain angle there are cases also where the cross sections decrease.
(2) The magnetic field effect is the most strong when the direction of the magnetic field is perpendicular to the collision plane, because of the cooperetive action of magnetic field and rotational coupling.
(3) The cross sections integrated over angle between the magnetic field and the incident velocity increase slowly with magnetic field.
(4) The lower the collision energy becomes, the more effective the magnetic field becomes.
2.We investigated the polarization effect, that is, the effect of the interaction between polarized target by moving multiply charged ion and magnetic field. However, this effect is pretty small in our cases.
3.The process, He^<2+>+H (1s)*He^+ (2l) +H^+, is corresponding to a resonance case and the possibility of chaos-like effect of magnetic field is predicted. However, in this case, there occurs two-type transitions, one is that due to phase by the Stark mixing and the other is that due to the rotational coupling. The transition at very large internuclear distance makes the transition mechanism very complex. We have made a proguram and are now performing calculatious using it.
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