First undulator installed in PETRA III

The 5.8-tons PETRA III undulator is lifted into its place.

The brilliant storage ring is reaching closure: on 21 January the first of the 14 undulator magnets that will generate the brilliant X-ray light for PETRA III was installed in the 300-metre-long experimental hall. The few remaining open sectors of the 2.3 kilometre particle accelerator are closing one by one.

The undulator magnets are the central components of the PETRA III facility. Strong permanent magnets, fitted together in alternating polarities, force the electron beam travelling at almost the speed of light on a zigzag course. The electrons then emit synchrotron light of very high energy and intensity that is used for research at the experimental stations. With a variety of construction forms and length of the undulator magnet array, PETRA III will produce light with different individual properties at the altogether 14 beamlines.

The outstanding features of PETRA III are its sharply focussed light beam – PETRA III will emit a light beam with a diameter of 30 nanometres – and the high energy and intensity. Researchers can use it for a feat variety of experiments, from probing new materials to molecular biology or medicine.