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Spectrophotometric studies of solutions at elevated temperatures and pressures: status and program for FY1961 and part of FY 1962

Description: A program was initiated on the spectrophotometric study of aqueous solution chemistry. The goal is operation at temperatures up to at least 330 deg C and at pressures up to 200 atm, and to near the critical point if this appears to be feasible. A spectrometer capable of operation under these extreme conditions is being designed. (W.L.H.)
Date: July 19, 1960
Creator: Biggers, R. E. & Chilton, J. M.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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General Chemistry Division quarterly report, July--September 1977

Description: Analytical research and development work is reported on multielement analysis, time-resolved spectroscopy, fluorescence analysis, ionization potential of NP, excited state chemistry, polarized x ray sources, potentiometric titration of Na, determination of TATB in DMSO, determination of nitrobenzene in TATB, analysis of explosive composites, mass spectrometer automation, mass spectra calculation, solids formation in geothermal brine, water quality laboratory automation, aerosol coagulation, and… more
Date: November 30, 1977
Creator: Harrar, J.E. (ed.)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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DEVELOPMENT OF PLUTONIUM BEARING FUEL MATERIALS. Progress Report for period July 1 through September 30, 1961

Description: Data are tabulated for the characteristic parameters of PuO/sub 2/ powders prepared by the continuous oxalate precipitation process. The results show that the PuO/sub 2/ surface area decreases almost linearly with calcination hold times at 760 deg C. A thermogravimetric study of the decomposition of Pu oxalate indicate the formation of an initial stable compound at ~ l00 deg C and a stable intermediate at ~ 300 deg C. Characteristic data are tabulated for UO/sub 2/ -5% PuO/sub 2/ and UO/sub 2/-… more
Date: October 31, 1962
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Discovery of A Very Bright, Strongly-Lensed z=2 Galaxy in the SDSS DR5

Description: We report on the discovery of a very bright z = 2.00 star-forming galaxy that is strongly lensed by a foreground z = 0.422 luminous red galaxy (LRG). This system was found in a systematic search for bright arcs lensed by LRGs and brightest cluster galaxies in the Sloan Digital Sky Survey Data Release 5 sample. Follow-up observations on the Subaru 8.2m telescope on Mauna Kea and the Astrophysical Research Consortium 3.5m telescope at Apache Point Observatory confirmed the lensing nature of this … more
Date: September 30, 2008
Creator: Lin, Huan; Buckley-Geer, Elizabeth; Allam, Sahar S.; Tucker, Douglas L.; Diehl, H.Thomas; Kubik, Donna et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The SEGUE Stellar Parameter Pipeline. III. Comparison with High-Resolution Spectroscopy of SDSS/SEGUE Field Stars

Description: The authors report high-resolution spectroscopy of 125 field stars previously observed as part of the Sloan Digital Sky Survey and its program for Galactic studies, the Sloan Extension for Galactic Understanding and Exploration (SEGUE). These spectra are used to measure radial velocities and to derive atmospheric parameters, which they compare with those reported by the SEGUE Stellar Parameter Pipeline (SSPP). The SSPP obtains estimates of these quantities based on SDSS ugriz photometry and low… more
Date: October 1, 2007
Creator: Allende Prieto, C.; Sivarani, T.; Beers, T. C.; Lee, Y. S.; Koesterke, L.; Shetrone, M. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Photometric Redshifts for the Dark Energy Survey and VISTA and Implications for Large Scale Structure

Description: We conduct a detailed analysis of the photometric redshift requirements for the proposed Dark Energy Survey (DES) using two sets of mock galaxy simulations and an artificial neural network code-ANNz. In particular, we examine how optical photometry in the DES grizY bands can be complemented with near infra-red photometry from the planned VISTA Hemisphere Survey (VHS) in the JHK{sub s} bands in order to improve the photometric redshift estimate by a factor of two at z > 1. We draw attention t… more
Date: November 1, 2007
Creator: Banerji, Manda; Abdalla, Filipe B.; Lahav, Ofer & Lin, Huan
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The Milky Way Tomography with SDSS. 2. Stellar Metallicity

Description: In addition to optical photometry of unprecedented quality, the Sloan Digital Sky Survey (SDSS) is producing a massive spectroscopic database which already contains over 280,000 stellar spectra. Using effective temperature and metallicity derived from SDSS spectra for {approx}60,000 F and G type main sequence stars (0.2 < g-r < 0.6), we develop polynomial models, reminiscent of traditional methods based on the UBV photometry, for estimating these parameters from the SDSS u-g and g-r color… more
Date: April 1, 2008
Creator: Ivezic, Zeljko; Sesar, Branimir; Juric, Mario; Bond, Nicholas; Dalcanton, Julianne; Rockosi, Constance M. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Feasibility of Measuring the Cosmological Constant [LAMBDA]and Mass Density [Omega]using Type Ia Supernovae

Description: We explore the feasibility of resurrecting the apparent magnitude-redshift relation for a 'standard candle' to measure the cosmological constant and mass density. We show that type Ia supernovae, if measured with 0.15 mag uncertainty out to a redshift of z = 1, may provide a good standard candle or calibrated candle for this purpose. The recent discovery of probable type Ia supernovae in the redshift range z = 0.3 to 0.5 (Perlmutter et al. 1994a, and 1994b) indicates that the flux of optical ph… more
Date: April 1, 1995
Creator: Goobar, A. & Perlmutter, S.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Measuring Type Ia Supernova Distances and Redshifts From TheirMulti-band Light Curves

Description: The distance and redshift of a type Ia supernova can bedetermined simultaneously through its multi-band light curves. This factmay beused for imaging surveys that discover and obtain photometry forlarge numbers of supernovae; so many that it would be difficult to obtaina spectroscopic redshift for each. Using available supernova-analysistools we find that there are several conditions in which a viabledistance--redshift can be determined. Uncertainties in the effectivedistance at z~;0.3 are domi… more
Date: August 12, 2007
Creator: Kim, Alex G. & Miquel, Ramon
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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A Generalized {ital K} Correction for Type Ia Supernovae: Comparing {ital R}-band Photometry Beyond {ital z=9.2} with B,V, and {ital R}-band Nearby Photometry

Description: Photometric measurements show that, as a group, nearby Type Ia supernovae follow similar light curves and reach similar peak magnitudes (Branch & Tammann 1992). Thus, these supernovae may serve as standard candles or calibrated candles at cosmological distances. Magnitudes of local and distant supernovae, both in the same filter band, are compared using a K correction to account for the different spectral regions incident on that filter. A generalized approach compares magnitudes in different b… more
Date: November 1, 1995
Creator: Kim, Alex; Goodbar, Ariel & Perlmutter, Saul
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The SEGUE Stellar Parameter Pipeline. 1. Description and Initial Validation Tests

Description: The authors describe the development and implementation of the SEGUE (Sloan Extension for Galactic Exploration and Understanding) Stellar Parameter Pipeline (SSPP). The SSPP derives, using multiple techniques, radial velocities and the fundamental stellar atmospheric parameters (effective temperature, surface gravity, and metallicity) for AFGK-type stars, based on medium-resolution spectroscopy and ugriz photometry obtained during the course of the original Sloan Digital Sky Survey (SDSS-I) and… more
Date: October 1, 2007
Creator: Lee, Young Sun; Beers, Timothy C.; Sivarani, Thirupathi; /Michigan State U. /Michigan State U., JINA; Allende Prieto, Carlos; Koesterke, Lars et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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In-line multiwavelength photometer for the determination of heavy metal concentrations

Description: An in-line photometer has been developed for continuous monitoring of uranium and plutonium concentrations in high radiation environments of nuclear fuel reprocessing plants. The instrument is equipped with multiple narrow band interference filters to monitor sample transmission in the 400- to 800-nm range. The filters are mounted in a rotating filter wheel which is located in front of a stationary tungsten halide light source. The monochromatic light from the respective optical filters is tran… more
Date: January 1, 1981
Creator: Bostick, D. T.; Strain, J. E.; Dixon, D. M.; McCue, D. D. & Bauer, M. L.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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PG1159-035: a New, Hot, Non-DA Pulsating Degenerate

Description: The star was observed with a computer-controlled high-speed photometer. The light curve showed nearly sinusoidal variations with a period of about 8 minutes and a peak-to-peak amplitude of about 0.02 magnitude. Power spectra of the light curves were calculated. They showed peaks corresponding to periods of 460 and 539 seconds. The effective temperature of the star was found to exceed 5 x 10/sup 4/ K; lack of circular polarization indicated that the star does not have a large surface magnetic fi… more
Date: January 1, 1979
Creator: McGraw, J. T.; Starrfield, S. G.; Liebert, J. & Green, R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Commercialization of a thick film solar cell. Quarterly technical progress report, January 1, 1980-March 31, 1980

Description: Initial problems encountered in the screen printing of CdS films related to an undesirable surface texture on the film surface have been resolved by modification of ink rheology. Improvements have been made in CdS films through modification in firing conditions, ink composition, and fluxing. The CdS 13 micron thick films are devoid of through pores and have a resistivity of 1.65 ohm cm. A laser probe technique was developed to determine macro variations in solar cell films.
Date: January 1, 1980
Creator: McDonald, G.D.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Single particle analysis with a 360/sup 0/ light scattering photometer

Description: Light scattering by single spherical homogeneous particles in the diameter range 1 to 20 ..mu..m and relative refractive index 1.20 is measured. Particle size of narrowly dispersed populations is determined and a multi-modal dispersion of five components is completely analyzed. A 360/sup 0/ light scattering photometer for analysis of single particles has been designed and developed. A fluid stream containing single particles intersects a focused laser beam at the primary focal point of an ellip… more
Date: June 1, 1979
Creator: Bartholdi, M.F.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Rarefaction velocities in shocked tantalum and the high-pressure melting point

Description: The optical analyzer technique has been used to determine the pressure at which shock compressed tantalum can no longer support a longitudinal elastic wave. At 295 GPa, the release wave velocity drops to a value consistent with a calculated bulk sound velocity, indicating partial melting. At higher shock pressures, the bulk sound velocity follows a constant rho ..gamma.. model, where ..gamma.. is the Grueneisen parameter. With these measurements we have identified melting on the Ta Hugonitot, a… more
Date: January 1, 1983
Creator: Brown, J. M. & Shaner, J. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Analysis of sodium and potassium in silicate rocks by a lithium metaborate fusion method. Final report, Volume 77-6

Description: The lithium tetraborate fusion method devised by Ingamells (1964) has been modified slightly to produce rapid and precise analysis of sodium and potassium contents in silicate rocks. The analytical method, procedure, and results are described briefly. (MHR)
Date: December 1, 1977
Creator: Nash, W. P. & Crecraft, H.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Composite design of an advanced airborne monitoring system

Description: Atmospheric chemistry investigations often require a multitude of measurements which can be obtained only through the utilization of airborne sampling platforms. Instrument limitations and the aircraft environment present several considerations for sampling-system design, including such factors as instrument sensitivities and response times, altitude effects, sampling intervals for acquiring samples, and physical compatibility with the aircraft. An aircraft system with an extensive evolutionary… more
Date: December 1, 1981
Creator: Busness, Kenneth M.; Alkezweeny, Abdul J.; Easter, Richard C.; Hales, Jeremy M. & Lee, Richard N.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Development and evaluation of an automated reflectance microscope system for the petrographic characterization of bituminous coals

Description: The development of automated coal petrographic techniques will lessen the demands on skilled personnel to do routine work. This project is concerned with the development and successful testing of an instrument which will meet these needs. The fundamental differences in reflectance of the three primary maceral groups should enable their differentiation in an automated-reflectance frequency histogram (reflectogram). Consequently, reflected light photometry was chosen as the method for automating … more
Date: October 1, 1980
Creator: Hoover, D. S. & Davis, A.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Supernova Models

Description: Recent progress in understanding the observed properties of Type I supernovae as a consequence of the thermonuclear detonation of white dwarf stars and the ensuing decay of the /sup 56/Ni produced therein is reviewed. Within the context of this model for Type I explosions and the 1978 model for Type II explosions, the expected nucleosynthesis and gamma-line spectra from both kinds of supernovae are presented. Finally, a qualitatively new approach to the problem of massive star death and Type II… more
Date: January 1, 1980
Creator: Woosley, S. E. & Weaver, T. A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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