Measurement of the orbit parameters at SOR-RING

In the 1992 summer shutdown, beam position monitors (BPM's) have been installed in SOR-RING as one of the R&D's for the future plan of a VUV high-brilliant source. They have been also aimed at measuring the closed orbit of the ring and correcting it by beam steerings that have been also installed at the same time as the BPM's. With these systems, we measured the closed orbit distortion (C.O.D.) at the first time since the ring had been constructed. Horizontal and vertical C.O.D.'s were then corrected within 1 mm by exciting the steerings and changing the RF frequency. We also measured the other orbit parameters such as betatron and dispersion functions, chromaticity and RF-cavity parameters. Moreover, it was proved in a recent machine study that SOR-RING is capable of accelerating the electrons up to 450 MeV or more from the present energy of 380 MeV. >