What happens to a positively-charged alpha particle directly hits the positively-charge nucleus?

When a positively-charged alpha particle directly hits a positively-charged nucleus, it experiences a strong electrostatic repulsion due to the like charges. This repulsion can cause the alpha particle to be deflected away from the nucleus rather than penetrate it. If the energy of the alpha particle is not sufficient to overcome the Coulomb barrier, it will simply bounce off. In some cases, if the particle approaches closely enough, it might interact through nuclear forces, but this is less common in direct collisions.