  In order to fulfil the recent thrust of Astatine radionuclides in the field
of nuclear medicine various production routes have been explored in the present
work. The possible production routes of $^{209-211}$At comprise both light and
heavy ion induced reactions at the bombarding energy range starting from
threshold to maximum 100 MeV energy. For this purpose, we have used the nuclear
reaction model codes TALYS, ALICE91 and PACE-II. Excitation functions of those
radionuclides, produced through various production routes, have been calculated
using nuclear reaction model codes and compared with the available measured
data. Contribution of various reaction mechanisms, like, direct, preequilibrium
and equilibrium reactions, to the total reaction cross section has been studied
using the codes. Result shows that equilibrium reaction mechanism dominates in
all cases over other reaction mechanisms.
