Power density distribution and associated thermal analysis of an elliptical polarizing undulator

The Taiwan Photon Source (TPS) project is planning to construct a third-generation synchrotron accelerator in Taiwan. This 3 GeV, 500 mA high-energy accelerator will support 20 beamlines for insertion devices (ID) and 24 beamlines for bending magnets (BM). We will undertake an in-depth investigation of the power density distribution and thermal analysis of the accelerator as an important part in the design of the photon absorbers, masks, and mirrors at the front end and in the beamline areas. An elliptically polarizing undulator (EPU) will be one of the primary ID sources for this accelerator and will have a different power density distribution from the other sources. We have derived a general elliptical polarizing EPU power density distribution for this source and have performed a mathematical approximation suitable for practical engineering applications. We will also present a thermal analysis of the helical undulator using Gaussian and unit step-function approximations.