A system and method for fabricating accelerator cavities comprises forming at least two half cavities and joining the half cavities with a longitudinal seal. The half cavities can comprise at least one of aluminum, copper, tin, and copper alloys. The half cavities can be coated with a superconductor or combination of materials configured to form a superconductor coating.

Heat dissipaters 120a, 120b are thermally coupled to a memory 220 and a CPU 230 (heat generating components) disposed on a top surface (a first surface) of a substrate 210. A frame 130 is thermally conductive and is attached above the top surface of the substrate 210. Openings 131 are formed in locations corresponding to locations in the frame 130 where the heat dissipaters 120a, 120b are provided. Elastic rubber elements 150 are thermally conductive and flexible, and thermally couple the heat dissipaters 120a, 120b to the frame 130. This configuration is capable of dissipating heat generated by the heat generating components even when the heat generating components generate amounts of heat that exceed the heat dissipation ability of the heat dissipaters thermally coupled to the heat generating components.

A system is described that includes a sputter target and a magnetic element array including multiple sets of magnets arranged to have a Hall-Effect region that extends along a length of the sputter target. The elongated sputtering electrode material tube is interposed between the magnetic array and an object to be deposited with a sputtered material from the sputter target. During a direct current high-power impulse magnetron sputtering operation, the system performs a depositing on a surface of the object by generating and controlling an ion and neutral particle flux by: providing a vacuum apparatus containing a sputter target holder electrode; first generating a high-power pulsed plasma magnetron discharge with a high-current negative direct current (DC) pulse to the sputter a target holder electrode; and second generating a configurable positive voltage kick pulse to the sputter target holder electrode after terminating the negative DC pulse.

A flange joint system for SRF cavities. The flange joint system includes a set of high force spring clamps that produce high force on the simple flanges of Superconducting Radio Frequency (SRF) cavities to squeeze conventional metallic seals. The system establishes the required vacuum and RF-tight seal with minimum particle contamination to the inside of the cavity assembly. The spring clamps are designed to stay within their elastic range while being forced open enough to mount over the flange pair. Upon release, the clamps have enough force to plastically deform metallic seal surfaces and continue to a new equilibrium sprung dimension where the flanges remain held against one another with enough preload such that normal handling will not break the seal.

A flange joint system for SRF cavities. The flange joint system includes a set of high force spring clamps that produce high force on the simple flanges of Superconducting Radio Frequency (SRF) cavities to squeeze conventional metallic seals. The system establishes the required vacuum and RF-tight seal with minimum particle contamination to the inside of the cavity assembly. The spring clamps are designed to stay within their elastic range while being forced open enough to mount over the flange pair. Upon release, the clamps have enough force to plastically deform metallic seal surfaces and continue to a new equilibrium sprung dimension where the flanges remain held against one another with enough preload such that normal handling will not break the seal.

A high performance accelerator structure and method of production. The method includes precision machining the inner surfaces of a pair of half-cells that are maintained in an inert atmosphere and at a temperature of 100 K or less. The method includes removing thin layers of the inner surfaces of the half-cells after which the roughness of the inner surfaces in measured with a profilimeter. Additional thin layers are removed until the inner surfaces of the half-cell measure less than 2 nm root mean square (RMS) roughness over a 1 mm.sup.2 area on the profilimeter. The two half-cells are welded together in an inert atmosphere to form an SRF cavity. The resultant SRF cavity includes a high accelerating gradient (E.sub.acc) and a high quality factor (Q.sub.0).

A high performance accelerator structure and method of production. The method includes precision machining the inner surfaces of a pair of half-cells that are maintained in an inert atmosphere and at a temperature of 100 K or less. The method includes removing thin layers of the inner surfaces of the half-cells after which the roughness of the inner surfaces in measured with a profilimeter. Additional thin layers are removed until the inner surfaces of the half-cell measure less than 2 nm root mean square (RMS) roughness over a 1 mm.sup.2 area on the profilimeter. The two half-cells are welded together in an inert atmosphere to form an SRF cavity. The resultant SRF cavity includes a high accelerating gradient (E.sub.acc) and a high quality factor (Q.sub.0).

Provided is a superconducting accelerating cavity 30 including: a cavity main body 10 formed of a superconducting material into a cylindrical shape; and a refrigerant tank 20 installed around the cavity main body 10 and storing a refrigerant which is supplied from the outside through a supply port 20a into a space formed between the refrigerant tank and the outer circumferential surface of the cavity main body 10, wherein the outer circumferential surface of the cavity main body 10 is coated with a metal coating layer 10a having a higher conductivity than the superconducting material.

Provided is a superconducting accelerating cavity 30 including: a cavity main body 10 formed of a superconducting material into a cylindrical shape; and a refrigerant tank 20 installed around the cavity main body 10 and storing a refrigerant which is supplied from the outside through a supply port 20a into a space formed between the refrigerant tank and the outer circumferential surface of the cavity main body 10, wherein the outer circumferential surface of the cavity main body 10 is coated with a metal coating layer 10a having a higher conductivity than the superconducting material.

A conduction cooling system for linear accelerator cavities. The system conducts heat from the cavities to a refrigeration unit using at least one cavity cooler interconnected with a cooling connector. The cavity cooler and cooling connector are both made from solid material having a very high thermal conductivity of approximately 110.sup.4 W m.sup.1 K.sup.1 at temperatures of approximately 4 degrees K. This allows for very simple and effective conduction of waste heat from the linear accelerator cavities to the cavity cooler, along the cooling connector, and thence to the refrigeration unit.