Extending the range of a low energy SR-source to hard X-rays

An outline design is presented for a SR-source providing high brilliance VUV/soft X-rays and high flux hard X-rays based on existing hardware of the BESSY I storage ring, which will be shut down by the end of 1999. Essential features are a 6-cell double bend achromat lattice, with low beta in three of the 6 long straight sections to facilitate the use of superconducting multipole wigglers. Beam optical implications are discussed together with technical modifications of existing hardware and possible operation at 1.0 GeV. A design of a 7.5 T multipole wiggler is given.