Results from 2D field calculations [11] for quadrupoles and dipoles have been investigated concerning the impact on Dynamic Aperture [10]. Alignment errors and orbit correction have been included. It has been found that the multipoles cut off all Dynamic Aperture outside the physical aperture which is simply due to the fact, that the multipole decomposition is only valid within the pole inscribed radius. Tracking including physical limits virtually does not show any Dynamic Aperture deterioration. Subsequent tests using data from 3D field calculations for quadrupoles and sextupoles have confirmed this result.
The vertical correctors with dipole coefficient b1 which are integrated into the sextupoles create a large decapole component b5. The ratio of the multipole coefficients b5/b1 is calculated to be 5.25 105 m-4. Assuming a linear scaling of b5 with b1 the Dynamic Aperture has been calculated for 200 distorted and orbit corrected machines operated in the D0 lattice mode. It has been shown that the Dynamic Aperture is only reduced for large momentum deviations dp/p>2%.