We consider a two-body quantum system in dimension one composed by a test
particle interacting with an harmonic oscillator placed at the position a>0.
At time zero the test particle is concentrated around the position R0 with
average velocity ±v0 while the oscillator is in its ground state. In a
suitable scaling limit, corresponding for the test particle to a semi-classical
regime with small energy exchange with the oscillator, we give a complete
asymptotic expansion of the wave function of the system in both cases R0<a
and R0>a.Comment: 23 page