Regenerable cryosorption pump with movable physical barrier and physical barrier thereof

A method of regenerating a cryopump having a movable cylindrical physical barrier, comprising:

• displacing said barrier from a storage position occupied during operation of said cryopump to a regeneration position intermediate a sorbent surface for sorbing helium molecules and a deuterium-tritium (DT) pumping surface for pumping hydrogen molecules, so as to isolate said sorbent surface from said DT pumping surface during regeneration;
• simultaneously warming said sorbent surface and said DT pumping surface;
• simultaneously but separately pumping molecules previously condensed and sorbed onto said surfaces to regenerate said pump;
• and
• retracting said barrier from said regeneration position to said storage position after regeneration to place said cryopump in operating condition.

A movable physical barrier for use in a regenerable cryosorption pump having a sorbent surface for sorbing helium molecules and a pumping surface for sorbing hydrogen isotopes, said barrier comprising:

• a cylindrical body open at a first end and closed at a second end;
• a circumferential baffle at said first end;
• and
• a retractable bellows at said second end for advancing and retracting said barrier from a storage position during operation of said pump to an active position during regeneration of said pump.