Analysis of the D0 Crane Rail as a Support for a Horizontal Lifeline

The D-Zero crane rail is analyzed for use as an anchor support for a one person Horizon{trademark} Horizontal Lifeline system that will span the pit area at D-Zero assembly hall. The lifeline will span 75 ft across the pit area, will be located out of the travel of the crane and above the concrete lentil wall. The crane rail is a suitable anchor for a one person Horizon TM Horizontal Lifeline system. The expected stress on the rail is 1,995 psi which has a factor of safety of 5.5 on the allowable stress. The anchor position is located 18 feet away from the concrete lentil wall and out of the travel of the overhead crane

A feasibility study of signal processing to improve antenna gain Final report

Feasibility of signal processor with phase isolator for adaptive antenna arra

Analysis of a Lifting Fixture to Hold a Steel Mandrel Horizontally from one End Support

A lifting fixture (drawing number 3823.113-MD-372382) that lifts large steel mandrels from one end through the mandrel's end support web is described. The mandrels are used as a mold to form carbon fiber cylinders. The mandrels are held from one end to allow the carbon cylinder to be pulled horizontally off the mandrel. Only mandrels as described in drawing numbers 3823.113-MD-358992 and 3823.1 13-MD-358994 are lifted by the fixture. The largest mandrel is 41 inches in diameter, 120 inches long, and weighs approximately 3,000 lbs. A detailed procedure for removing the carbon cylinder from the steel mandrel is given in the Appendix. The fixture is to be supported only using Fermilab Forklift 10207 or equivalent. The forklift has a nameplate capacity of 12,000 lbs 24 inches from the mast at an elevation of 130 inches from the floor. The forklift forks must be removed from the truck prior to using the fixture. The forklift is to be used to support the mandrels only during the lifting operation and is not to be used to transport the mandrels. Stresses at the lifting fixture are shear stresses on the support brackets due to the overall weight of the mandrel and moment loads due to the cantilever style suppOrt. The moment on the forklift due to the overhanging weight of the mandrel is calculated. Stresses in the mandrel due to the method of support are also described

Study of a signal processor employing a synthetic phase isolator

Evaluation of signal data processor employing synthetic phase isolator techniqu

Measuring the flatness of focal plane for very large mosaic CCD camera

Large mosaic multiCCD camera is the key instrument for modern digital sky survey. DECam is an extremely red sensitive 520 Megapixel camera designed for the incoming Dark Energy Survey (DES). It is consist of sixty two 4k$\times$2k and twelve 2k x 2k 250-micron thick fully-depleted CCDs, with a focal plane of 44 cm in diameter and a field of view of 2.2 square degree. It will be attached to the Blanco 4-meter telescope at CTIO. The DES will cover 5000 square-degrees of the southern galactic cap in 5 color bands (g, r, i, z, Y) in 5 years starting from 2011. To achieve the science goal of constraining the Dark Energy evolution, stringent requirements are laid down for the design of DECam. Among them, the flatness of the focal plane needs to be controlled within a 60-micron envelope in order to achieve the specified PSF variation limit. It is very challenging to measure the flatness of the focal plane to such precision when it is placed in a high vacuum dewar at 173 K. We developed two image based techniques to measure the flatness of the focal plane. By imaging a regular grid of dots on the focal plane, the CCD offset along the optical axis is converted to the variation the grid spacings at different positions on the focal plane. After extracting the patterns and comparing the change in spacings, we can measure the flatness to high precision. In method 1, the regular dots are kept in high sub micron precision and cover the whole focal plane. In method 2, no high precision for the grid is required. Instead, we use a precise XY stage moves the pattern across the whole focal plane and comparing the variations of the spacing when it is imaged by different CCDs. Simulation and real measurements show that the two methods work very well for our purpose, and are in good agreement with the direct optical measurements.Comment: Presented at SPIE Conference,Ground-based and Airborne Instrumentation for Astronomy III, San Diego, 201

Measurements of charge diffusion in deep-depletion CCDs by optical diffraction

The charge diffusion is measured in back illuminated, fully depleted, 250 {micro}m thick CCDs by imaging the diffraction pattern of a double slit. The CCDs studied are the focal plane detectors for the Dark Energy Camera (DECam) instrument currently under construction for the Dark Energy Survey (DES). The results presented here indicate that the dispersion of charge due to diffusion can be kept below the DES specification ({sigma}{sub d} < 7.0 {micro}m)