STATUS OF THE PETRA III DAMPING WIGGLERS

After mid-2007, the present PETRA storage ring at DESY will be reconstructed towards a dedicated third generation light source operating at 6 GeV. An emittance reduction down to 1 nmmrad can be achieved by means of damping wigglers. 20 permanent magnet wigglers will be installed in two of the long straights of the machine. The wiggler segments are compact fixed gap devices surrounded by iron enclosures to reduce the leakage flux. Each device will provide a damping integral of 4 T2m per segment and generate a synchrotron radiation power of 42 kW. Every wiggler segment will be followed by an SR-absorber to protect all downstream components, the accumulated on-axis power of about 120 kW will be taken up by a final absorber at the damping section end. The wiggler’s magnetic design, field properties and correction schemes have previously been proven by a short prototype. At present, the first full length (4m) prototype wiggler has been assembled and characterized magnetically. Figure 1: Layout of a regular cell in the damping section