Non-evaporable getter performance in the Photon Factory electron storage ring

A non-evaporable getter (NEG) was tested in the Photon Factory in the pressure range 10-11 to 10-9 torr. To test the pumping performance with gas load, one NEG unit was installed in the newly constructed vacuum duct and the other in a fully outgassed duct. The NEGs under both situations worked well under these conditions, as did the distributed ion pumps (DIP). The pumping speed of the NEG for hydrogen seems to be less than the nominal value. An additional pumping is required for pumping methane. A titanium sublimation pump is more effective in pumping carbon monoxide than the NEG. (author)