A method for regenerating a cryopump that includes a cooler including a first stage part and a second stage part, and configured to cool the first stage part and the second stage part with a high pressure refrigerant; a cryopanel including a first panel which is cooled by the first stage part and a second panel which is cooled by the second stage part; a cryopump vessel configured to surround the cryopanel and including a radiation shield that surrounds the first stage part; a first heater provided in the first panel; and a second heater provided in the second panel, the method comprising a temperature increasing process of increasing temperatures of the radiation shield and the first panel by turning on the first heater, a roughing process of controlling a roughing valve configured to regulate vacuum within the cryopump vessel in a state where the cryopump vessel is kept at a pressure at which solid state ice can sublimate into gas state vapor, a purging process of supplying a purge gas into the cryopump vessel, and a cool-down process of lowering the temperatures of the first panel and the second panel.

A method for regenerating a cryopump that includes a cooler including a first stage part and a second stage part, and configured to cool the first stage part and the second stage part with a high pressure refrigerant; a cryopanel including a first panel which is cooled by the first stage part and a second panel which is cooled by the second stage part; a cryopump vessel configured to surround the cryopanel and including a radiation shield that surrounds the first stage part; a first heater provided in the first panel; and a second heater provided in the second panel, the method comprising a temperature increasing process of increasing temperatures of the radiation shield and the first panel by turning on the first heater, a roughing process of controlling a roughing valve configured to regulate vacuum within the cryopump vessel in a state where the cryopump vessel is kept at a pressure at which solid state ice can sublimate into gas state vapor, a purging process of supplying a purge gas into the cryopump vessel, and a cool-down process of lowering the temperatures of the first panel and the second panel.

An apparatus and process for cooling down a liquid hydrogen or other cryogenic fluid pump can be configured to allow for a quick startup that also helps minimize hydrogen losses. Some embodiments can utilize a blow-by circuit configured and arranged to support the cryogenic cooldown operation for the pump that can minimize hydrogen loss while allowing substantially improved pump startup times. Some embodiments can utilize at least one temperature sensor to monitor temperature and an adjustable control valve that can facilitate the flow of the fluid utilized to perform the cooldown of the pump.

An apparatus and process for cooling down a liquid hydrogen or other cryogenic fluid pump can be configured to allow for a quick startup that also helps minimize hydrogen losses. Some embodiments can utilize a blow-by circuit configured and arranged to support the cryogenic cooldown operation for the pump that can minimize hydrogen loss while allowing substantially improved pump startup times. Some embodiments can utilize at least one temperature sensor to monitor temperature and an adjustable control valve that can facilitate the flow of the fluid utilized to perform the cooldown of the pump.

A cryopump comprising:a pump inlet, a two stage refrigerator; a first stage array thermally coupled to a first stage of said two stage refrigerator; and a cryopanel structure coupled to a second stage of said two stage refrigerator is disclosed. The cryopanel structure comprises at least three flat panels. The first stage array is mounted between the pump inlet and the cryopanel structure, and comprises a plurality of slats, the plurality of slats each being mounted such that a side of each of the plurality of slats closest to the cryopanel structure is substantially aligned and offset longitudinally with respect to a corresponding one of said at least three flat panels.

A cryopump comprising:a pump inlet, a two stage refrigerator; a first stage array thermally coupled to a first stage of said two stage refrigerator; and a cryopanel structure coupled to a second stage of said two stage refrigerator is disclosed. The cryopanel structure comprises at least three flat panels. The first stage array is mounted between the pump inlet and the cryopanel structure, and comprises a plurality of slats, the plurality of slats each being mounted such that a side of each of the plurality of slats closest to the cryopanel structure is substantially aligned and offset longitudinally with respect to a corresponding one of said at least three flat panels.

A refrigerator is provided, including rare earth cold accumulating material particles filled in a cold accumulating vessel. The rare earth cold accumulating material particles are a rare earth oxide or a rare earth oxysulfide. The rare earth cold accumulating material particles define a sintered body. An average crystal grain size of the sintered body is 0.5 to 5 μm, a porosity of the sintered body is 10 to 50 vol. %, and an average pore size of the sintered body is 0.3 to 3 μm. In an arbitrary cross-section of the rare earth cold accumulating material particles, a number of pores per a unit area of 10 μm×10 μm is 20 to 70.

A refrigerator is provided, including rare earth cold accumulating material particles filled in a cold accumulating vessel. The rare earth cold accumulating material particles are a rare earth oxide or a rare earth oxysulfide. The rare earth cold accumulating material particles define a sintered body. An average crystal grain size of the sintered body is 0.5 to 5 μm, a porosity of the sintered body is 10 to 50 vol. %, and an average pore size of the sintered body is 0.3 to 3 μm. In an arbitrary cross-section of the rare earth cold accumulating material particles, a number of pores per a unit area of 10 μm×10 μm is 20 to 70.

A vacuum pumping system comprising: a high pressure getter pump configured to operate from an initial pressure of between 10 and 10.sup.−2 mbar to a second pressure between 10.sup.−3 mbar and 10.sup.−6 mbar and at least one high vacuum pump configured to operate at higher vacuums than the high pressure getter pump, the two pumps being mounted on a same flange, the flange being configured to mount the vacuum pumping system to a vacuum chamber.

A vacuum pumping system comprising: a high pressure getter pump configured to operate from an initial pressure of between 10 and 10.sup.−2 mbar to a second pressure between 10.sup.−3 mbar and 10.sup.−6 mbar and at least one high vacuum pump configured to operate at higher vacuums than the high pressure getter pump, the two pumps being mounted on a same flange, the flange being configured to mount the vacuum pumping system to a vacuum chamber.