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The Vacuum group is responsible for the design, fabrication, installation, test, operation and maintenance of the          vacuum systems of the SSRF. The Vacuum group has developed the vacuum systems and key components for the     Insertion Devices (IDs), the linear accelerator, the booster and the storage ring of the SSRF.

The storage ring vacuum system is the most important part of the SSRF vacuum systems. It provides an ultra-high      vacuum environment for the electrons circulated along the storage ring. The storage ring has 20 cells separated by RF gate valves. Each cell includes 14 Sputter Ion Pumps (SIPs) and 11 Titanium Sublimation Pumps (TSPs). Some of     the SIPs equipped with Non Evaporable Getters (NEGs). There are about 90 ion gauges and several Residual Gas    Analyzers (RGAs) to monitor the pressure of the storage ring vacuum chambers.

The storage ring vacuum system consists of 316LN stainless steel vacuum chambers, RF bellows, photon absorbers and various types of vacuum pumps. The anti-chamber stainless steel vacuum chamber has an octagonal cross section of 68 mm×35 mm (H× V). Two vacuum chambers, coated with copper to improve electrical conductivity, are used for the in-air insertion devices and they have a length of 2 meters and an oval cross section of 68 mm×10 mm (H ×V). After assembling and pre-baking, vacuum chambers are installed into the storage ring as one module and do not need to bake in-situ. All the residual radiation power is taken away by cooling water via photon absorbers made of          OFHC.

In the past few years, the high operational performance of the vacuum system was achieved and the vacuum level is    better than 5×10-8 Pa at the beam current of 220 mA .

The Vacuum group has developed many vacuum systems and cryogenic facilities for both domestic and foreign          institutes including:

Shanghai Soft X-ray Free Electron Laser Test Facility (SXFEL)

Dalian Coherent Light Source (DCLS)

Linear Accelerator for Brazilian Light Source

Insertion Devices including in-air undulators, in-vacuum undulators (IVUs), cryogenic permanent magnet undulator (CPMU), superconducting undulator(SCU).

ADS Injector-II

Muon Ionization Cooling Experiment (MICE)

Applied Particle Accelerators


Meanwhile, the Vacuum group is also actively involved in developing cutting-edge technologies and equipments, such as RF bellows, photon absorbers, Al alloy-made long vacuum chamber and so on.


The group is currently composed of 9 members.



Li Wang


Xiao Hu


Zhishan Wang


Yiyong Liu


Yongmei Wen


Shuhua Wang


Qisheng Tang


Xuejun Li


Lin Zhang



Stainless steel vacuum chamber for accelerators


  Photon absorbers and RF bellows                 Pumps: SIP, TSP and NEG (in SIP)


Vacuum chamber and cooling system for CPMU