No abstract

To facilitate high-sensitivity soft X-ray magnetic circular dichroism experiments, a dynamic local bump system has been developed at the SRRC storage ring. This system was devised to vary dynamically the vertical slope of the electron beam in a bending magnet, producing, in the electron orbit plane, soft X-rays with an alternating elliptical polarization. The local bump was created by using two pairs of vertical correctors located on each side of the bending magnet. The bump strength coef®cient was obtained both from calculated estimation and from measured beam-response matrices. Control electronics for proper bump strength settings were designed to incorporate the existing orbitcorrector function. A corresponding graphic user interface was implemented so that the bump amplitude could be easily adjusted. The performance of this system is presented. Disturbance on the stored electron beam orbit was observed whilē ipping the corrector polarity during EPBM (elliptical polarization from bending magnets) operation. A local feedback loop, developed to eliminate such disturbance on other beamlines, is also described.

No abstract

For the purpose of lattice optimization, eighteen individual quadrupole power supplies was installed in the SRRC storage ring in March 1997 to replace the three quadrupole family power supplies. In order to accomodate newly installed and already existed power supplies, the control interface of Taiwan Light Source (TLS) has been rejuvenated recently. The new control interface has improved drastically on control speed in comparison with the existed interface. Operation of the power supply system from device level to system level is reorganized to make control and access easier. This new control interface provides capability from complex operation such as lattice file loading, magnet degaussing, to file energy ramping scheme, etc. Performance of this power supply control interface including hardware components and software applications is presented.

No abstract