XMAP: a differential algebra tool generating accelerator maps

The authors describe XMAP, a Fortran program which produces the map across an accelerator beam line, in the form of a truncated power series expansion, by calling the DA (differential algebra) package algorithms. This beam line, for example, could be one complete turn of the SSC. The expansion variables are a free mixture of any or all of the six phase space coordinates and of optical parameters, like the length or strength of a set of quadrupoles. The scope of applications for XMAP is quite broad. For example, applications which have been considered for the SSC include: lattice design, dependence of resonance widths on optical parameters, parametric dependence of smear and tune shifts, and parametric maps for operational simulations. The performance of XMAP is illustrated by means of a simple example, the expansion of a FODO cell