Trajectory calculation for the dipole magnets of INDUS-2 storage ring

In the optics simulations of any synchrotron the hard edge approximation of the magnetic field is considered and the fringe field effect is generally avoided. But in the real situation the magnetic field does not follow the hard edge pattern and there is a gradual fall and rise of the field at the edges. In addition to this there is the asymmetry in the magnetic field with respect to magnet centre. Due to the magnetic fringe field extended to well outside at both of the edges the charged particle starts experiencing the force well before the magnet entrance and continue up to well outside the magnet exit. Because of the above two factors the particle trajectory get deviated from the reference one. In this paper we present the method of calculation and correction of the particle trajectory under the influence of these errors for the Indus-2 storage ring. (author)