A differential pumping system for one of the ESRF ultra-high vacuum beamlines

✍ Scribed by M Renier; A Draperi

• Publisher: Elsevier Science
• Year: 1997
• Tongue: English
• Weight: 288 KB
• Volume: 48
• Category: Article
• ISSN: 0042-207X
• DOI: 10.1016/s0042-207x(97)00012-2

✦ Synopsis

When low photon energy ranges (3-40 keV1 are required in a synchrotron beamline, the use of beryllium windows to isolate the machine vacuum from the beamline is forbidden. In addition, if the operating pressure of the beamline is three orders of magnitude larger that of the machine, the only way of realizing vacuum insufation is to install a differential pumping system. The 1020 European Synchrotron Radiation Facility beamline dedicated to magnetic scattering studies imposes pa~icularly difficult conditions: no bery~tium window is al/owed; it may operate at 70p7mbar pressure white the machine vacuum must be kept at 7O-" mbar. In addition the beam size may be as large as 12 x 40 mm", which imposes rather large sections of the connecting pipes, and the maximum power is over 3kW. A differential pumping system meeting these requirements for most common gases has been built. It includes two 4001/s ion pumps connected in series

with tubes of, respectively, 6.3 and 14.1 l/s. Details on the construction and performances are reported in this paper.