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EUVE photometry of SS Cygni: Dwarf nova outbursts and oscillations

Description: The authors present EUVE Deep Survey photometry and AAVSO optical measurements of the 1993 August and 1994 June/July outbursts of the dwarf nova SS Cygni. The EUV and optical light curves are used to illustrate the different response of the accretion disk to outbursts which begin at the inner edge and propagate outward, and those which begin at the outer edge and propagate inward. Furthermore, the authors describe the properties of the quasi-coherent 7--9 s sinusoidal oscillations in the EUV fl… more
Date: May 15, 1995
Creator: Mauche, C.W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Astrometry with the MACHO Data Archive

Description: We present the preliminary results of our astrometric study of stellar motions along the lines of sight of the Magellanic Clouds and the Galactic bulge. We find that we are able to select stars with proper motions as small as 0.03 inch/yr from five years of PSF photometry due to the characteristic nature of the shapes the light curves of HFM stars. This shape arises from the proper motion of the object relative to the initial fixed centroid location where all photometry of the object is perform… more
Date: October 15, 2000
Creator: Drake, A. J.; Alcock, C.; Allsman, R.; Alves, D. R.; Axelrod, T. S.; Becker, A. C. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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STRUCTURE FUNCTION ANALYSIS OF LONG-TERM QUASAR VARIABILITY

Description: In our second paper on long-term quasar variability, we employ a much larger database of quasars than in de Vries, Becker & White. This expanded sample, containing 35,165 quasars from the Sloan Digital Sky Survey Data Release 2, and 6,413 additional quasars in the same area of the sky taken from the 2dF QSO Redshift Survey, allows us to significantly improve on our earlier conclusions. As before, all the historic quasar photometry has been calibrated onto the SDSS scale by using large numbers o… more
Date: November 15, 2004
Creator: de Vries, W; Becker, R; White, R & Loomis, C
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Process Development Quarterly Report. Part I

Description: Progress is preserted on studies of the Waxco process, new raw materials, high (NH/sub 4/)/sub 2/Csub 2/O/sub 4/ insoluble in MCW UF/su b 4/, recovery of HF and U from MgF/sub 2/ bomb slag, study of U metal with respect to metal quality, C contamination in cast U, vacuum fusion 0 determination, pyroelectric con centration methods for improving B sensitivity, grinding sample preparations for spectrographic analysis, and determination of N in U metal. (For preceding report see NYO-1353). (M.C.G.)
Date: July 15, 1953
Creator: Ruehle, A. E. & Shepardson, J. U.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Summary Technical Report for the Period July 1, 1956 to September 1, 1956

Description: The activities of the Technical Division, including the HNO/sub 3/ recovery process, a study of UO/sub 3/ factors as related to the production of metal-grade UF/sub 4/, a thermobalance investigation of starch as a reducing agent for UO/sub 3/, reduction of UF/sub 4/ to uranium by a thermite type reaction, melting and casting of Nb-U alloy, uranium recovery from scrap materials, preparation of uranium shot, cal cium reduction of ThO/sub 2/ production of thorium ingots, "wet chemical" and spectro… more
Date: October 15, 1956
Creator: Simmons, J. W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Supernova / Acceleration Probe: a Satellite Experiment to Study the Nature of the Dark Energy

Description: The Supernova/Acceleration Probe (SNAP) is a proposed space-based experiment designed to study the dark energy and alternative explanations of the acceleration of the Universe's expansion by performing a series of complementary systematics-controlled astrophysical measurements. We here describe a self-consistent reference mission design that can accomplish this goal with the two leading measurement approaches being the Type Ia supernova Hubble diagram and a wide-area weak gravitational lensing … more
Date: August 15, 2005
Creator: Aldering, G.; Althouse, W.; Amanullah, R.; Annis, J.; Astier, P.; Baltay, C. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
open access

Revealing the Jet Structure of Grb 030329 With High Resolution Multicolor Photometry

Description: We present multicolor optical observations of the nearby (z = 0.1685) GRB030329 obtained with the same instrumentation over a time period of 6 hours for a total of an unprecedented 475 quasi-simultaneous B V R observations. The achromatic steepening in the optical, which occurs at t {approx} 0.7 days, provides evidence for a dynamic transition of the source, and can be most readily explained by models in which the GRB ejecta are collimated into a jet. Since the current state-of-the-art modeling… more
Date: March 15, 2006
Creator: Gorosabel, Javier; Castro-Tirado, A. J.; Ramirez-Ruiz, E.; Granot, J.; Caon, N.; Cairos, L. M. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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