Abstract: Apparatus for measuring gas comprising a gas sensing unit having a gas inlet membrane and being evacuated by a sputter ion pump via a restrictive conductance. Said conductance has a very low value relative to the pumping speed of the pump, whereby a change in the pumping speed of the pump causes substantially no change in the pumping speed with which the gas sensing unit is evacuated, so that the output signal of said gas sensing unit is a true reflection of the gas entering said inlet, without distortion which would otherwise be caused by changes in pumping speed of said pump.

Abstract: Gate valve having a closure member mounted on a swinging arm pivotally mounted for movement transversely of the axis of the valve openings. A wedge member carried by the arm drives the closure member in a direction parallel to the axis of the openings when moved longitudinally of the arm. An actuator pivots a cam which bears against the wedge member to swing the arm to a predetermined position in which the closure member is aligned with the openings and thereafter to move the cam to drive the closure member axially and seal one of the openings. Resilient members urge the closure member toward its retracted position and prevent the wedge member from moving forward until the arm reaches the predetermined position.

Abstract: In an electron beam heating and/or evaporator, an electron gun projects a beam of electrons over an arcuate beam path to a crucible containing a target material for heating and/or evaporating the target material in use. The electron beam passes between a pair of generally parallel magnetically permeable pole pieces of a beam focus magnet energized by a primary source of magnetomotive force to produce a main field transverse to the direction of the arcuate electron beam. This main field causes the electron beam to take the arcuate trajectory. An auxiliary electromagnet structure is magnetically coupled between the pole pieces in a region adjacent the electron beam. This auxiliary electromagnet structure includes a first set of windings for skewing the main magnetic field to produce lateral deflection of the beam spot over the target area and a second electromagnetic coil energizable to increase or decrease the intensity of the main field to provide a longitudinal sweep of the beam spot on the target.

Abstract: The vacuum chamber for an Auger analyzer is provided with a side access port through which interchangeable specimen trays are inserted and installed on a rotatable support structure. The specimen tray has a plurality of peripheral specimen sites and a Faraday cup probe structure similarly positioned but affixed to the support structure. The Faraday cup facilitates calibrating the ion beam and positioning the ion beam and the cup at the focal point of the electron beam. The support structure is subsequently rotated to sequentially expose each specimen to the beams.

Abstract: A standing-wave linear charged particle accelerator is disclosed which comprises a plurality of interlaced substructures, with each substructure having a plurality of accelerating cavities disposed along the particle beam path and having side cavities disposed away from the beam path for electromagnetically coupling the accelerating cavities. A standing radio-frequency electromagnetic wave is supported in each substructure, with the wave in each substructure being phase with respect to the wave in every other substructure so that the particle beam will experience a maximum energy gain throughout its path through the accelerator. This interlaced substructure configuration minimizes the transit time of the particles across the gap of each accelerating cavity and makes it possible to operate the accelerator without radio-frequency breakdown at a power level that provides a substantially higher average value of the accelerating electric field along the beam path than has heretofore been obtainable.

Abstract: A cold cathode ionization gauge controller utilizing a periodically varying potential across the gauge tube at higher pressure and substantially constant potential at low pressure provides a wide-range pressure measurement capability from about 10.sup.-.sup.1 to about 10.sup.-.sup.7 torr.

Abstract: A leak detection system comprising a mass spectrometer tuned to detect the presence of helium in a gas sample, and a gas sample inlet member comprising a multichannel array of capillary passages. In an ideal embodiment, the gas sample inlet member comprises a segment of commercially obtainable multistrand electrical wire encased in an insulating plastic sheath. The spaces between the individual strands provide the capillary passages for the admission of the gas sample.

Abstract: In a magnetically confined sputter-ion vacuum pump a multi-apertured anode electrode is interposed between a pair of reactive cathode electrode plates. An evacuable envelope encloses the anode and cathode electrodes and a magnetic circuit surrounds the vacuum envelope for producing a glow discharge confining magnetic field extending axially of the apertures in the anode. The reactive cathode plates include peripheral sealing flanges for compressing a sealing gasket into sealing engagement with a pair of sealing surfaces at opposite ends of a tubular main body portion of the envelope. A clamping ring structure, having a bolt circle formed therein, serves to clamp the two reactive cathode plates to the main body and also serves as an integral part of the magnetic circuit. Water coolant channels are brazed to the outer surfaces of the cathode plates for cooling same in use.

Abstract: The tubular stainless steel structure of a nuclear reactor fuel rod thermal simulator is heated to nuclear fuel rod operating temperatures by means of a gaseous glow discharge established within the tubular structure. In a preferred embodiment a length of the simulated fuel rod is internally clad with tungsten, or Mo or alloys thereof, hermetically sealed at both ends and filled with a glow discharge sustaining gas such as hydrogen or helium. A center electrode structure, as of tungsten, or Mo or alloys, is centrally disposed within the gas filled tubular envelope. Power is applied between the center electrode and the outer tubular envelope for initiating and sustaining the glow discharge for heating the outer tubular envelope to nuclear fuel rod simulating temperature.

Abstract: Gate valve having a closure member mounted on a swinging arm pivotally mounted for movement transversely of the axis of the valve openings. A wedge member carried by the arm drives the closure member in a direction parallel to the axis of the openings when moved longitudinally of the arm. An actuator pivots a cam which bears against the wedge member to swing the arm to a predetermined position in which the closure member is aligned with the openings and thereafter to move the cam to drive the closure member axially and seal one of the openings. Resilient members urge the closure member toward its retracted position and prevent the wedge member from moving forward until the arm reaches the predetermined position.

Abstract: The heat-transfer capability of a movable-electrode gas-filled arc lamp is optimized. In the preferred embodiment, the movable electrode is the anode which is mounted at the base of the lamp coaxialy with and spaced apart from the cathode. Low-voltage starting of the lamp is provided by solenoid means for moving the anode briefly into contact with the cathode and then withdrawing the anode from contact with the cathode so that a difference of electrical potential develops between the cathode and the anode, which is sufficient to ionize the gas in the gap formed therebetween. The arc thereby generated in the gap follows the withdrawing anode to its fully spaced-apart position with respect to the cathode. A heat sink member is disposed within the gas-filled envelope at the base of the lamp, and a metal collar is affixed to and surrounds the movable anode. The collar provides thermally conductive contact with the heat sink member when the anode is in its fully spaced-apart position with respect to the cathode.

Abstract: In an x-ray treatment machine a charged particle accelerator or cobalt source is provided for producing a field of high energy x-ray radiation for application to a body, for treatment thereof. The radiation machine includes collimators and field shaping structures for shaping the field of x-ray radiation applied to the body. The high energy x-ray radiation intercepted by the field shaping and collimating structures produces high energy secondary electrons by a number of different atomic processes. These energetic secondaries contaminate the shaped radiation field applied to the body being treated. The contaminating high energy electrons, if not eliminated, substantially increase the dosage of radiation delivered to the surface of the body.

Abstract: A method and apparatus for detecting a leak of an alkali metal in liquid form in a structure such as the heat transfer system of a nuclear reactor. When alkali metal leaks from its containment structure and thereupon comes into contact with a compound containing hydrogen which can be displaced by the alkali metal, a chemical reaction occurs by which hydrogen gas is generated. The hydrogen gas so generated will diffuse very rapidly throughout the region proximate to the sodium leak. The hydrogen compound can be present in a variety of physical forms. The compound barium hydroxide is especially suitable as a source for the generation of hydrogen gas. Water vapor in air or in an inert gas also provides a suitable hydrogen source. A sensor located within the region of the alkali metal leak will sense the presence of hydrogen gas and will thereupon activate an alarm or recording device.

Abstract: Outgassing of hydrogen from high-vacuum system components made of stainless steel and similar alloys can be minimized if the metal surfaces to be exposed to the vacuum are treated according to the technique disclosed herein. First, an adherent layer comprising a mixture of oxides and nitrides is formed on the metal surfaces. This oxide and nitride mixture layer serves as a barrier to hydrogen diffusion. Then, a reduced layer having a low heat of adsorption for water is formed on the exposed surface of the oxide and nitride mixture layer. This reduced layer is made sufficiently thin to preclude outgassing of significant amounts of hydrogen into the vacuum system. In effect, a vacuum envelope is formed which outgasses only from a thin layer of reduced oxide.

Abstract: A leak detector system comprising a mass spectrometer tuned to detect the presence of helium test gas is prepared for operation by reference to the partial pressure of helium in air.

Abstract: An alkali metal corrosion resistant vacuum tight metal-to-ceramic seal is formed between a high alumina ceramic body and a refractory alkali metal resistant metal member, such as Cb-1Zr, by interposing a powdered brazing mixture comprising by weight a majority of elemental columbium powder and a second metal powder selected from the class consisting of iron and nickel, and firing the assembly in vacuum at a temperature between 1500.degree.C and 1675.degree.C to partially melt a portion of the powder to form a melted bonding phase component interstitially of the undissolved columbium particles for bonding the ceramic to the metal part.

Abstract: Apparatus to indicate the temperature of an X-ray tube target includes an analog storage circuit to simulate the heat energy stored. Input signals representing the current and the voltage of the electron beam in the tube are multiplied to give a signal representing the instantaneous power input. The power signal is integrated in the storage circuit to give a temperature signal representing the total heat input. The temperature signal is dissipated by a cooling curve circuit representing the heat loss with time. An indicator reads the temperature signal.Input voltage and current signals are processed to refer them to ground before multiplication. The current signal is corrected to set its zero value. The voltage signal derived from a transformer primary is corrected for transformer regulation. To eliminate spurious inputs the power signal is gated to the storage circuit only when a measured current is flowing.

Abstract: In a high energy X-ray therapy machine, an accelerator accelerates a beam of electrons to energies of several MEV. The electron beam is directed, generally via a beam deflector, onto an X-ray target to produce X-rays for treating a patient. The accelerator and beam deflector are often carried within a rotatable gantry structure, movable for radiating the patient through a series of angular positions or ports. A plurality of ionization chamber radiation detectors are disposed in the radiation field surrounding the beam path of the accelerated electron beam. Ionization current signals are compared from a plurality of the detectors to derive an error signal determinative of a deviation of the beam from an intended beam path. The error signal is utilized to energize beam steering coils for steering the beam along the predetermined beam path.

Abstract: A gaseous discharge sputter coating apparatus is described for sequentially sputtering different materials onto discrete batches of substrate objects. The apparatus includes a chamber defining a controlled environment capable of sustaining a gaseous discharge, a table within the chamber for supporting separate batches of substrate objects, and means for sustaining a gaseous discharge within the chamber. A plurality of target electrode structures is also provided, each of which has a surface in the chamber which has a layer on it of one of the materials desired to be coated onto the substrate objects. The target electrode structures are part of the wall of the controlled environment chamber, and each includes an insulating material separating it from the remainder of the wall. In order to obviate the necessity of including a ground shield around each of the target electrodes, only that portion of the electrode within the chamber having the material on it has power applied to it to cause the sputtering.

Abstract: In a gas-filled lamp an arc is initiated by withdrawal of a stinger electrode from contact with a stationary cathode, with subsequent transfer of the arc to the gap between the cathode and a stationary anode. The anode is cylindrical; and the stinger is elongate and is movably mounted within and electrically insulated from the anode. The cathode is elongate, having a long axis parallel to but spaced apart from the long axis of the stinger. The stinger contacts the cathode at other than the tip of the cathode, thereby precluding continual impacting of the stinger on the cathode tip with concomitant blunting of the cathode tip during the use cycle of the lamp. A magnetic core is affixed to the stinger, whereby the stinger can be moved by the energization of a solenoid. The magnetic core is apertured to provide a dashpot effect to damp the motion of the stinger.