Advances in MAD-X using PTC

For the last few years the MAD-X program makes use of the Polymorphic Tracking Code (PTC) to perform calculations related to beam dynamics in the nonlinear regime. An important new feature is the extension of the matching module to allow fitting of non-linear parameters to any order. Moreover, calculations can now be performed with parameter dependence defined in the MAD-X input. In addition, the user can access the PTC routines for the placement of a magnet with arbitrary position and orientation. This facilitates the design of non-standard lattices, in particular since a 3D visualization of a lattice is now available. For the LHC studies during commissioning it is of special interest that one has access to within the thick PTC elements which allows e.g. to find PTC Twiss parameters at any point in the ring.