Aluminium ultrahigh vacuum system for the 3 GeV TPS synchrotron light source

6th Vacuum and Surface Sciences Conference of Asia and Australia

Hsiung, G.Y.^1 ; Chang, C.C.^1 ; Chen, C.L.^1 ; Wu, L.H.^1 ; Cheng, C.M.^1 ; Chan, C.K.^1 ; Yang, Y.C.^1 ; Hsueh, H.P.^1 ; Hsu, S.N.^1 ; Chen, J.R.^1,2

National Synchrotron Radiation Research Center, 101 Hsin-Ann Road, Hsinchu 30076, Taiwan^1

Institute of Biomedical Engineering and Environmental Science, National Tsing Hua University, Hsinchu 30043, Taiwan^2

关键词: Circulating beam;    Cooling components;    Dimensional control;    Electron storage ring;    Non-evaporable getters;    Synchrotron light source;    Thermal outgassing;    Ultra-high-vacuum systems;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/439/1/012034/pdf
DOI  :  10.1088/1742-6596/439/1/012034

来源: IOP

【 摘 要 】

The 3-GeV Taiwan Photon Source (TPS) is a large accelerator and synchrotron light source of circumference 518.4 m. The electron storage ring of TPS requires an ultrahigh-vacuum pressure per beam current less than 2×10-10Pa/mA in the beam duct to maintain a long life of the circulating beam without scattering of ions by residual gases. Aluminium alloys used for the beam ducts have a benefit of greater thermal conductivity that simplifies the structure of vacuum vessels built with the cooling components. Machining completely free of oil applied to the aluminium chambers followed by cleaning with ozonized water and welding in house provide a precise dimensional control within 0.3 mm and a clean surface with a small rate ∼ 6.4×10-12Pa m/s of thermal outgassing after baking at 150°C for 24 h. The assembled ion pump with non-evaporable getter pump is capable of evacuating the chamber to a pressure -9Pa. The average pressure inside the duct is expected to be sufficiently small. The clean process to manufacture the aluminium ultrahigh vacuum system is described.