Abstract: A gas discharge vuv light source is disclosed having low inductance and a high intensity output covering a range from 90 A to 6000 A. The source comprises a capillary defining a first bore removably, and at least partially, mounted within an air-cooled ceramic insulator; a first, hollow, cylindrical electrode having a removable insert defining a second bore disposed in end-to-end, coaxial relationship with one end of the capillary, and a second, hollow electrode which is configured to define a cavity and so as both to support the insulator such that the first and second bores are coaxially aligned with the cavity, and to releasably support either a tubular insert or a finned plate insert; and metallic vacuum seals connecting the electrodes to the insulator such that a gas-tight seal is formed between each electrode and the insulator at locations isolated from the first and second bores and from the cavity.

Abstract: A polarization analyzer is disclosed which comprises a planar mirror mounted at an angle of incidence of 45.degree. with respect to the radiation on a mount which is rotatable about an axis parallel to the optical axis of the radiation. A detector is also provided which is pivotably mounted with respect to the mirror such that the detector is pivotable between a first position wherein the detector detects the radiation incident on the mirror and a second position wherein the detector detects the radiation reflected by the mirror.

Abstract: Ion chambers adapted for use with radiant energy in the vacuum ultraviolet and X-ray spectral regions are provided wherein the ion repeller and collector electrodes are configured to provide an electric field therebetween which has a non-uniform potential gradient allowing a photon beam to be passed through a region of low field strength. A further aspect of the configuration of the ion repeller and collector electrodes is the elimination of the need for guard rings.