Raytheon

About: Raytheon is a company organization based out in Waltham, Massachusetts, United States. It is known for research contribution in the topics: Signal & Antenna (radio). The organization has 15290 authors who have published 18973 publications receiving 300052 citations.

An Ultraviolet/Optical Atlas of Bright Galaxies

Abstract: We present wide-field, imagery and photometry of 43 selected nearby galaxies of all morphology types at ultraviolet and optical wavelengths. The ultraviolet images, in two broad bands at 1500 Angstroms and 2500 Angstroms, were obtained by the Ultraviolet Imaging Telescope (UIT) during the Astro-1 Spacelab mission. The UV images have approx. 3" resolution, and the comparison sets of ground-based, CCD images (in one or more of B, V, R, and H alpha ) have pixel scales and fields of view closely matching the UV frames. The atlas consists of multiband images together with plots of UV/optical radial surface brightnesses, colors and other associated photometric parameters such as half-light radii. In an appendix, we discuss the sensitivity of different wavebands to a galaxy's star formation history in the form of "history weighting functions" and the importance of UV observations as probes of evolution during the past 10-1000 Myr. We find that UV galaxy morphologies are usually significantly different from visible band morphologies as a consequence of spatially inhomogeneous stellar populations. Differences are quite pronounced for systems in the middle range of Hubble types, Sa through Sc, but less so for ellipticals or late-type disks. Normal ellipticals and large spiral bulges are fainter and more compact in the UV. They typically exhibit smooth and unresolved far-UV profiles with, however, far-UV/optical color gradients which are larger than any at optical/IR wavelengths. The far-UV light in these cases is probably produced by extreme horizontal branch stars and their descendants in the dominant, low-mass, metal-rich population.

Integrated, reconfigurable man-portable modular system

Abstract: There is described an integrated reconfigurable man-portable communication system (100), adapted particularly for use in military or law enforcement tactical situations, including a modular compact computer (201a) with mission oriented hardware and software which provides the focal point for integration of various peripheral systems. The reconfigurable man-portable system (100) provides a ballistic helmet (402) with an integrated audio headset assembly (450). The helmet (402) also includes a modular heads-up display assembly (432) for providing remote viewing via a helmet mounted laser detection system (408,410), weapon mounted thermal weapons site (525), remote video system (535), and laser range finder/digital compass assembly (530). The heads-up display assembly (432) and the audio headset assembly (450) provides the user with tactical information such as; 360 degree laser detection from helmet mounted detectors (408, 410), target location for direct and indirect target engagement from the weapon mounted laser range finder/digital compass assembly (530), and navigational positioning from a global positioning system (245) and individual radio module (243) integrated within a modular load carrying device (601). The integration and modularity of the man-portable system (100) provides a flexible, mission oriented system capable of providing the user with enhanced awareness and communications ability.

First all-sky upper limits from LIGO on the strength of periodic gravitational waves using the Hough transform

Abstract: We perform a wide parameter-space search for continuous gravitational waves over the whole sky and over a large range of values of the frequency and the first spin-down parameter. Our search method is based on the Hough transform, which is a semicoherent, computationally efficient, and robust pattern recognition technique. We apply this technique to data from the second science run of the LIGO detectors and our final results are all-sky upper limits on the strength of gravitational waves emitted by unknown isolated spinning neutron stars on a set of narrow frequency bands in the range 200–400 Hz. The best upper limit on the gravitational-wave strain amplitude that we obtain in this frequency range is 4.43×10^(-23).

Phase Equilibria in the Ferrite Region of the System Fe—Co—O

Abstract: Phase relations in the system Fe-Co-O have been determined between 1000° and 1300°C in oxygen pressures of 0.01 to 20 atm. Only the portion of the system between CoFe2O4 and Co3O4 was considered in order to determine those conditions under which a complete series of solid solutions could be prepared. No field width on either side of oxygen stoichiometry was detected for solid solutions between CoFe2O4 and Co3O4.