欧洲同步辐射装置ESRF的Joel Chavanne博士于10月底来我所访问，将于10月28日做题为“Insertion Devices，From third-generation light sources to ultra-small emittance rings”的学术报告，欢迎各位老师、同学参加！ 

　　报告题目：Insertion Devices，From third-generation light sources to ultra-small emittance rings 

　　报 告 人：Joel Chavanne，ESRF 

　　主 持 人：王九庆 副所长 

　　报告时间：10月28日(周一)，下午14:30 

　　报告地点：主楼C305会议室 

　　报告摘要： 

　　The technology of Insertion Devices (IDs) has evolved considerably over the past twenty years. This is due to a large demand for IDs, linked to the construction of many third-generation synchrotron light sources worldwide. 

　　Being the first facility of this kind built in the early 1990s, the European Synchrotron Radiation Facility (ESRF) has pioneered a number of developments in the field of Insertion Devices. This includes new types of magnetic structures, magnetic measurements techniques, field correction methods and studies on the interaction of IDs with a stored electron beam. 

　　The present trends in most existing facilities are largely centred on the development of short-period small gap undulators, such as In-Vacuum Undulators (IVUs) and the recently developed Cryogenic Permanent Magnet Undulators. Superconducting undulators are also being developed in some facilities. 

　　As a result of these developments, the brilliance of undulator sources could be pushed up by more than one order of magnitude. After this, however, any significant further gain in brilliance would only be achievable by reducing the existing few nanometre-radians of horizontal emittance by one or two orders of magnitude. The ESRF is presently involved in the design study of an ‘ultra-small emittance’ storage ring, in view of replacing the existing magnet layout with a new lattice. The resulting potential impact on Insertion Device requirements in terms of field quality needs to be studied to determine if our present achievements are still suitable. 

　　报告人简介： 

　　Following his PHD in electrical engineering, Joel Chavanne joined the ESRF in 1988 to setup the Insertion Device laboratory for building high quality permanent magnet undulators and wigglers as needed by third generation light sources. 

　　He has actively contributed to the magnetic design of insertion devices and new field correction methods known as multipoles and spectrum shimming. He played a significant role in the development of the 3D magnetic codes for Insertion devices which led to the well known RADIA software. 

　　Since 2001, Joel Chavanne is leading the ESRF Insertion Device group who has build more than 120 Insertion devices of various types including a number of structures with pioneering concept. He is presently also involved in the design of advanced magnets for a new ultra small emittance lattice in the frame of the ESRF accelerator upgrade.