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Re-evaluation of Ball 3X Recovery System improvements, 105-B, D, DR, F, and H

Description: Since the installation of Ball 3X equipment on the older reactors, several inadvertent ball drops have been experienced, many of which have required considerable recovery time. Furthermore, it is very probable that these recovery times be significantly increased subsequent to the proposed installation of air accelerated vertical safety rods. Because of this, interest has been expressed by reactor operations personnel toward provision of a ball recovery system which would substantially reduce these outages.
Date: May 27, 1957
Creator: Walker, R. C.
Partner: UNT Libraries Government Documents Department

The VLBA Imaging And Polarimetry Survey at 5 GHz

Description: We present the first results of the VLBA Imaging and Polarimetry Survey (VIPS), a 5 GHz VLBI survey of 1,127 sources with flat radio spectra. Through automated data reduction and imaging routines, we have produced publicly available I, Q, and U images and have detected polarized flux density from 37% of the sources. We have also developed an algorithm to use each source's I image to automatically classify it as a point-like source, a core-jet, a compact symmetric object (CSO) candidate, or a complex source. Using data from the Sloan Digital Sky Survey (SDSS), we have found no significant trend between optical flux and 5 GHz flux density for any of the source categories. Using the velocity width of the H{beta} emission line and the monochromatic luminosity at 5100 to estimate the central black hole mass, M{sub BH}, we have found a weak trend between M{sub BH} and 5 GHz luminosity density for objects with SDSS spectra. Ongoing optical follow-up for all VIPS sources will allow for more detailed explorations of these issues. The mean ratio of the polarized to total 5 GHz flux density for VIPS sources with detected polarized flux density ranges from 1% to 20% with a median value of about 5%. This ratio is a factor of {approx}3 larger if only the jet components of core-jet systems are considered and is noticeably higher for relatively large core-jet systems than for other source types, regardless of which components (i.e., core, jet, or both) are considered. We have also found significant evidence that the directions of the jets in core-jet systems tend to be perpendicular to the electric vector position angles (EVPAs). The data is consistent with a scenario in which {approx}24% of the polarized core-jets have EVPAs that are anti-aligned with the directions of their jet components ...
Date: November 20, 2006
Creator: Helmboldt, J.F.; Taylor, G.B.; Tremblay, S.; Fassnacht, C.D.; Walker, R.C.; Myers, S.T. et al.
Partner: UNT Libraries Government Documents Department

A combined analysis of SLAC experiments on deep inelastic e-p and e-d scattering

Description: We report recent work on the extraction of R = {sigma}{sub L}/{sigma}{sub T} and the structure function F{sub 2} over a large kinematic range, which is based on a reanalysis of deep inelastic {var_epsilon} {minus} p and {var_epsilon} {minus} d scattering cross sections measured at SLAC between 1970 and 1985. All these data were corrected for radiative effects using improved versions of external and internal radiative correction procedures. The data from seven individual experiments were normalized to those from the recent high-precision SLAC experiment E140. We find that R{sub p} = R{sub d}, as expected in QCD. The value of R is higher than predicted by QCD even when target-mass effects are included. This difference indicates that additional dynamical higher-twist effects may be present. The structure functions F{sub 2}p and F{sub 2}d were also extracted from the full data sets of normalized cross sections using an empirical fit to R. These structure functions were then compared with data from the CERN muon scattering experiments BCDMS and EMC. We find that our data are consistent with the EMC data, if the latter are multiplied by a normalization factor of 1.07. No single, uniform normalization factor can be applied to the BCDMS data that will bring them into agreement with the SLAC data in the region of overlap.
Date: August 1, 1989
Creator: Whitlow, L. W.; Bodek, A.; deBarbaro, P.; Dasu, S.; Harada, H.; Krasny, M. W. et al.
Partner: UNT Libraries Government Documents Department