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Frozen-in viscoelasticity has a significant, yet previously overlooked, impact on the refractive index profile of optical fibers and can serve as the basis for novel fiber devices. Viscoelastic strains can be frozen into an optical fiber during draw, or by cooling down a drawn fiber from high temperature while under tension. The resulting refractive index perturbation can exceed 0.003, exhibits minimal birefringence, and is concentrated in the highest viscosity region of the fiber. We have developed a quantitative theory for the refractive index perturbation, which is in excellent agreement with measured data. We have harnessed frozen-in viscoelasticity to create novel high-performance all-fiber beam expanders achieving mode field diameters in excess of 40 /spl mu/m. These beam expanders are suitable for low-cost high-volume manufacturing and can serve as the basis for high-power single-mode fiber (SMF) connectors, since their lower power density improves reliability during high-power operation. Because of the significant reduction in free-space diffraction associated with the enlarged mode field diameter, these beam expanders may be suitable for MEMS applications, or for coupling between optical fiber terminations and optical fiber sources or detectors.

A cosmic ray experiment to be flown on an Orbiting Geophysical Observatory (OGO-E) consists of Cerenkov, scintillation, and solid state detector telescopes with associated electronics. Primary emphasis in this paper is placed upon description of the 256 channel pulse height analyzer and coincidence system electronics. Description of the three parameter system used for the scintillation telescope is emphasized since it is the most representative of the three telescope systems. A pulse height analysis is performed on each of the three photomultiplier tube outputs. Results are sent into the spacecraft data handling system. Circuits in the analyzer discussed in detail because of their improved performance over previously used circuits are a low noise charge sensitive amplifier, an RC pulse shaping technique, a delay line gated oscillator and a peak detecting circuit for pulse shape discrimination. In conjunction with the basic analyzer a coincidence system using a basic circuit for threshold discrimination and coincidence gating is described. Precise control of resolution down to 100 nanoseconds is obtainable.

Information on the detailed charge and energy spectra of galactic and solar cosmic rays is required for a better understanding of the production, acceleration and modulation of those cosmic rays. This experiment consists of a set of three detector assemblies to measure the differential energy spectra of protons and heavier nuclei through calcium (Z = 20) in the range of 400 Kev to 1 Bev/nucleon, and an extensive electronics system to implement the logic, perform pulse height analysis, measure particle fluxes, monitor experiment performance and interface with the OGO data system. The detector systems described here are the design of F. B. McDonald, V. K. Balasubrahmanyan, D. E. Hagge, B. Teegarden and G. H. Ludwig of the Goddard Space Flight Center.

A project was undertaken to analyze the processes associated with individual creativity in industrial research organizations and the effects of the company environment and management policies on the results of research and development (R and D) activities. Interviews were held with two hundred and nine technical researchers drawn from the fundamental, applied, and development staffs of seventeen private industrial firms, one research institute, one university laboratory, and the members of a creative engineering seminar for industry held at Stanford. One aspect of the study concerned the dichotomy of research specialist vs generalist. Most of the men participating in this study had broad technical and personal interests even though their current job assignments might each involve a definite specialization. Data on a wide range of characteristics and attitudes of research people are presented.