The problem with which this investigation is concerned is that of making experimental measurements of proton-induced K-shell x-ray production cross sections and to study the dependence of these cross sections upon the energy of the incident proton. The measurements were made by detection of the characteristic x-rays emitted as a consequence of the ionization of the K-shell of the atom. The method for relating this characteristic x-ray emission to the x-ray production cross section is discussed in this work.The measurements made in this investigation have a twofold use. First, they add to needed information for testing of theoretical calculations of inner atomic electron shell ionization by ion impact. There are three basic theories which describe inner shell ionization processes. Two of these theories, the Binary Encounter Approximation (BEA) and the Plane Wave Born Approximation (PWBA), apply to the proton energy range studied in this work. The BEA is a semi-classical treatment, and the PWBA is a quantum mechanical treatment.Corrections have been suggested to the PWBA to account for the change in the binding energy of the ionized shell caused by the penetration of the incident ion into this shell. Thisgives three theoretical predictions applicable to this work.Two of the theories, the BEA and the PWBA with binding energy corrections, give nearly equivalent predictions for the ionization cross section of an element when bombarded by protons in the energy range investigated in this work.The PWBA predicts cross sections which may differ from the other predictions by as much as a factor of two. Because of insufficient data to totally test these three theories, itis not known which theory best predicts the ionization cross sections for the range of proton energies studied in this work.The measurements made here compliment existing data and aid in the testing of these theories.The second use of these measurements is in the field of application of x-ray analysis. High resolution non-dispersive Since the available data is limited, the measurements of this work are a useful contribution to the information needed for studies in x-ray analysis techniques.The K-shell ionization and x-ray production cross sections for Fe, Co, Cu, Zn, Ga, Ge, and As were measured for proton impact in the range 0.5 to 2.0 MeV. Several of these elements were chosen for this investigation because of the need for x-ray production cross sections to facilitate the characterization of materials used in semi-conductor devices.The ionization cross sections for Fe, Co, Cu, Zn, Ga, Ge, andAs were found to be 242 23, 173 15, 94.1 7,8, 70.9 6.9, 56.4 4.6, 36.5 2.7 and 27.1 2.1 barns respectively at 2.0 MeV.These measurements agree to within less than 17 per cent with the predictions of the BEA and the PWBA with binding energy corrections.The predictions o6f the PWBA exceed the measured values by as much as a factor of two at the maximum deviation.It is concluded from a study of the energy dependence of these cross sections that the BEA and PWBA with bi...

Applications of fast imaging employ both streak cameras and fast framing techniques. Image intensifier tubes are gated to provide fast two-dimensional shutters of 2-3 ns duration with shatter ratios of greater than 10 6 and resolution greater than 10 4 pixels. Shutters of less than 1 ns have been achieved with experimental lubes. Characteriza tion data demonstrate the importance of tube and pulser design.Streak cameras are used to simultaneously record temporal and intensity information from up to 200 spatial points. Streak cameras are combined with lemote readout fordownhole uses and .-.re coupled to fiber optic cables for uphole uses. Optical wavelength multiplexing is being studied as a means of compressing additional image data onto optical fibers. Performance data demonstrate trade-offs between im age resolution and system sensitivity.

Optical shutters with exposure times approaching 1 ns have been achieved by gating either the photocathode or the microchannel plate of 18 -mm proximity-focused microchannel plate intensifier tubes. We present measurements of the shutter performance, including the total optical gate, uniformity vs time, resolution, linearity, and dynamic range, for a number of intensifier tubes under various types of pulsing configurations.Properties of intensifier tubes related to fast gating and limitations on the gating speed imposed by the intensifier tube geometry are discussed. We also give results with a specially modified intensifier in which all but a 3 mm x 18 mm portion of the photocathode was masked off by an opaque metallic undercoating, along with preliminary results of gating third -generation (GaAs photocathode) intensifier tubes. A characterization procedure used to evaluate the performance of each optical shutter is discussed, along with a review of fast electrical pulsers suitable for gating intensifier tubes.

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