Speaker
Description
In-vacuum undulators (IVUs), in which permanent magnets are placed inside the
vacuum chamber to allow for a narrower gap operation, have two technical
challenges; one is a strong attractive force between acting on magnetic arrays,
and the other is a stringent requirement on magnetic materials to avoid
demagnetization during the bake-out process and long-term operation. The former
imposes a complicated design on mechanical and vacuum structures, while the
latter limits the possibility of using permanent magnets with high remanence. To
solve these issues, several technical developments have been made, such as the
force cancellation, modularization of magnetic arrays, and enhancement of
resistance against demagnetization by means of a special magnetic configuration.
In this talk, performances of new IVUs built upon these technologies are
presented to reveal their effectiveness for constructing high-performance IVUs
in a cost-effective manner.
