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Integrated Management of all Historical, Operational and Future Decomissioning Solid ILW at Dounreay

Description: This paper describes major components of the Dounreay Site Restoration Plan, DSRP to deal with the site's solid intermediate level waste, ILW legacy. Historic solid ILW exists in the Shaft (disposals between 1959 and 1977), the Wet Silo (operated between 1973 and 1998), and in operating engineered drummed storage. Significant further arisings are expected from future operations, post-operations clean out and decommissioning through to the completion of site restoration, expected to be complete by about 2060. The raw waste is in many solid forms and also incorporates sludge, some fissile material and hazardous chemical components. The aim of the Solid ILW Project is to treat and condition all this waste to make it passively safe and in a form which can be stored for a substantial period, and then transported to the planned U.K. national deep repository for ILW disposal. The Solid ILW Project involves the construction of head works for waste retrieval operations at the Shaft and Wet Silo, a Waste Treatment Plant and a Conditioned Waste Store to hold the conditioned waste until the disposal facilities become available. In addition, there are infrastructure activities to enable the new construction: contaminated ground remediation, existing building demolition, underground and overground services diversion, sea cliff stabilization, and groundwater isolation at the Shaft.
Date: February 27, 2002
Creator: Graham, D.
Partner: UNT Libraries Government Documents Department

Electroweak Symmetry Breaking via UV Insensitive Anomaly Mediation

Description: Anomaly mediation solves the supersymmetric flavor and CP problems. This is because the superconformal anomaly dictates that supersymmetry breaking is transmitted through nearly flavor-blind infrared physics that is highly predictive and UV insensitive. Slepton mass squareds, however, are predicted to be negative. This can be solved by adding D-terms for U(1)_Y and U(1)_{B-L} while retaining the UV insensitivity. In this paper we consider electroweak symmetry breaking via UV insensitive anomaly mediation in several models. For the MSSM we find a stable vacuum when tanbeta< 1, but in this region the top Yukawa coupling blows up only slightly above the supersymmetry breaking scale. For the NMSSM, we find a stable electroweak breaking vacuum but with a chargino that is too light. Replacing the cubic singlet term in the NMSSM superpotential with a term linear in the singlet wefind a stable vacuum and viable spectrum. Most of the parameter region with correct vacua requires a large superpotential coupling, precisely what is expected in the"Fat Higgs'" model in which the superpotential is generated dynamically. We have therefore found the first viable UV complete, UV insensitive supersymmetry breaking model that solves the flavor and CP problems automatically: the Fat Higgs model with UV insensitive anomaly mediation. Moreover, the cosmological gravitino problem is naturally solved, opening up the possibility of realistic thermal leptogenesis.
Date: February 19, 2004
Creator: Kitano, Ryuichiro; Kribs, Graham D. & Murayama, Hitoshi
Partner: UNT Libraries Government Documents Department

Hydrochemistry of selected parameters at the Raft River KGRA, Cassia County, Idaho

Description: Low to moderate temperature (< 150/sup 0/C) geothermal fluids are being developed in the southern Raft River Valley of Idaho. Five deep geothermal wells ranging in depth from 4911 feet to 6543 feet (1490 to 1980 meters) and two intermediate depth (3858 feet or 1170 meters) injection wells have been drilled within the Raft River KGRA. Several shallower (1423-500 feet or 430-150 meters) wells have also been constructed to monitor the environmental effects of geothermal development of the shallower aquifer systems. Sampling of water from wells within the KGRA has been conducted since the onset of the project in 1974. Five analytical laboratories have conducted analyses on waters from the KGRA. Charge-balance error calculations conducted on the data produced from these laboratories indicated that data from three laboratories were reliable while two were not. A method of equating all data was established by using linear regression analyses on sets of paired data from various laboratories. The chemical data collected from the deep geothermal wells indicates that a two reservoir system exists within the Raft River KGRA. Each reservoir is associated with a major structural feature. These features are known as the Bridge Fault System (BFS) and the Narrows Structure (NS).
Date: January 1, 1981
Creator: Graham, D.L.; Ralston, D.R. & Allman, D.W.
Partner: UNT Libraries Government Documents Department

Predicting the Cosmological Constant from the Causal Entropic Principle

Description: We compute the expected value of the cosmological constant in our universe from the Causal Entropic Principle. Since observers must obey the laws of thermodynamics and causality, the principle asserts that physical parameters are most likely to be found in the range of values for which the total entropy production within a causally connected region is maximized. Despite the absence of more explicit anthropic criteria, the resulting probability distribution turns out to be in excellent agreement with observation. In particular, we find that dust heated by stars dominates the entropy production, demonstrating the remarkable power of this thermodynamic selection criterion. The alternative approach-weighting by the number of&quot;observers per baryon&quot; -- is less well-defined, requires problematic assumptions about the nature of observers, and yet prefers values larger than present experimental bounds.
Date: May 1, 2007
Creator: Bousso, Raphael; Bousso, Raphael; Harnik, Roni; Kribs, Graham D. & Perez, Gilad
Partner: UNT Libraries Government Documents Department

A Universe without Weak Interactions

Description: A universe without weak interactions is constructed that undergoes big-bang nucleosynthesis, matter domination, structure formation, and star formation. The stars in this universe are able to burn for billions of years, synthesize elements up to iron, and undergo supernova explosions, dispersing heavy elements into the interstellar medium. These definitive claims are supported by a detailed analysis where this hypothetical ''Weakless Universe'' is matched to our Universe by simultaneously adjusting Standard Model and cosmological parameters. For instance, chemistry and nuclear physics are essentially unchanged. The apparent habitability of the Weakless Universe suggests that the anthropic principle does not determine the scale of electroweak breaking, or even require that it be smaller than the Planck scale, so long as technically natural parameters may be suitably adjusted. Whether the multi-parameter adjustment is realized or probable is dependent on the ultraviolet completion, such as the string landscape. Considering a similar analysis for the cosmological constant, however, we argue that no adjustments of other parameters are able to allow the cosmological constant to raise up even remotely close to the Planck scale while obtaining macroscopic structure. The fine-tuning problems associated with the electroweak breaking scale and the cosmological constant therefore appear to be qualitatively different from the perspective of obtaining a habitable universe.
Date: April 7, 2006
Creator: Harnik, Roni; Kribs, Graham D. & Perez, Gilad
Partner: UNT Libraries Government Documents Department

Predicting the Cosmological Constant from the CausalEntropic Principle

Description: We compute the expected value of the cosmological constant in our universe from the Causal Entropic Principle. Since observers must obey the laws of thermodynamics and causality, it asserts that physical parameters are most likely to be found in the range of values for which the total entropy production within a causally connected region is maximized. Despite the absence of more explicit anthropic criteria, the resulting probability distribution turns out to be in excellent agreement with observation. In particular, we find that dust heated by stars dominates the entropy production, demonstrating the remarkable power of this thermodynamic selection criterion. The alternative approach--weighting by the number of ''observers per baryon''--is less well-defined, requires problematic assumptions about the nature of observers, and yet prefers values larger than present experimental bounds.
Date: February 20, 2007
Creator: Bousso, Raphael; Harnik, Roni; Kribs, Graham D. & Perez, Gilad
Partner: UNT Libraries Government Documents Department

Geothermal Modeling of the Raft River Geothermal Field

Description: This interim report presents the results to date of chemical modeling of the Raft River KGRA. Earlier work indicated a northwest-southeast anomaly in the contours. Modeling techniques applied to more complete data allowed further definition of the anomaly. Models described in this report show the source of various minerals in the geothermal water. There appears to be a regional heat source that gives rise to uniform conductive heat flow in the region, but convective flow is concentrated near the upwelling in the Crook well vicinity. Recommendations are made concerning field expansion and additional work needed to refine the overall reservoir model.
Date: November 1, 1979
Creator: Overton, H.L.; Chaney, R.E.; McAtee, D.L. & Graham, D.L.
Partner: UNT Libraries Government Documents Department

Gravitational Baryogenesis

Description: We show that a gravitational interaction between the derivative of the Ricci scalar curvature and the baryon-number current dynamically breaks CPT in an expanding universe and, combined with baryon-number-violating interactions, can drive the universe towards an equilibrium baryon asymmetry that is observationally acceptable.
Date: March 2, 2004
Creator: Davoudias, Hooman; Kitano, Ryuichiro; Kribs, Graham D.; Murayama, Hitoshi & Steinhardt, Paul J.
Partner: UNT Libraries Government Documents Department

The Minimal Supersymmetric Fat Higgs Model

Description: We present a calculable supersymmetric theory of a composite&quot;fat'&quot; Higgs boson. Electroweak symmetry is broken dynamically through a new gauge interaction that becomes strong at an intermediate scale. The Higgs mass can easily be 200-450 GeV along with the superpartner masses, solving the supersymmetric little hierarchy problem. We explicitly verify that the model is consistent with precision electroweak data without fine-tuning. Gauge coupling unification can be maintained despite the inherently strong dynamics involved in electroweak symmetry breaking. Supersymmetrizing the Standard Model therefore does not imply a light Higgs mass, contrary to the lore in the literature. The Higgs sector of the minimal Fat Higgs model has a mass spectrum that is distinctly different from the Minimal Supersymmetric Standard Model.
Date: November 26, 2003
Creator: Harnik, Roni; Kribs, Graham D.; Larson, Daniel T. & Murayama, Hitoshi
Partner: UNT Libraries Government Documents Department

Discovering Higgs Bosons of the MSSM using Jet Substructure

Description: We present a qualitatively new approach to discover Higgs bosons of the MSSM at the LHC using jet substructure techniques applied to boosted Higgs decays. These techniques are ideally suited to the MSSM, since the lightest Higgs boson overwhelmingly decays to b{bar b} throughout the entire parameter space, while the heavier neutral Higgs bosons, if light enough to be produced in a cascade, also predominantly decay to b{bar b}. The Higgs production we consider arises from superpartner production where superpartners cascade decay into Higgs bosons. We study this mode of Higgs production for several superpartner hierarchies: m{sub {tilde q}},m{sub {tilde g}} &gt; m{sub {tilde W}},{sub {tilde B}} &gt; m{sub h} + {mu}; m{tilde q};m{sub {tilde q}},m{sub {tilde g}} &gt; m{sub {tilde W}},{sub {tilde B}} &gt; m {sub h,H,A} + {mu}; and m{sub {tilde q}},m{sub {tilde g}} &gt; m{sub {tilde W}} &gt; m{sub h} + {mu} with m{sub {tilde B}} {approx} {mu}. In these cascades, the Higgs bosons are boosted, with pT &gt; 200 GeV a large fraction of the time. Since Higgs bosons appear in cascades originating from squarks and/or gluinos, the cross section for events with at least one Higgs boson can be the same order as squark/gluino production. Given 10 fb{sup -1} of 14 TeV LHC data, with m{sub {tilde q}} {approx}&lt; 1 TeV, and one of the above superpartner mass hierarchies, our estimate of S{radical} B of the Higgs signal is sufficiently high that the b{bar b} mode can become the discovery mode of the lightest Higgs boson of the MSSM.
Date: June 1, 2010
Creator: Kribs, Graham D.; Martin, Adam; Roy, Tuhin S. & Spannowsky, Michael
Partner: UNT Libraries Government Documents Department

A Comparison of Three Criteria Employed in the Selection of Regression Models Using Simulated and Real Data

Description: Researchers who make predictions from educational data are interested in choosing the best regression model possible. Many criteria have been devised for choosing a full or restricted model, and also for selecting the best subset from an all-possible-subsets regression. The relative practical usefulness of three of the criteria used in selecting a regression model was compared in this study: (a) Mallows' C_p, (b) Amemiya's prediction criterion, and (c) Hagerty and Srinivasan's method involving predictive power. Target correlation matrices with 10,000 cases were simulated so that the matrices had varying degrees of effect sizes. The amount of power for each matrix was calculated after one or two predictors was dropped from the full regression model, for sample sizes ranging from n = 25 to n = 150. Also, the null case, when one predictor was uncorrelated with the other predictors, was considered. In addition, comparisons for regression models selected using C_p and prediction criterion were performed using data from the National Educational Longitudinal Study of 1988.
Date: December 1994
Creator: Graham, D. Scott
Partner: UNT Libraries

Federal tax policy and infrastructure financing: a report to the Office of Technology Assessment, U.S. Congress

Description: This report starts out by discussing in details the Tax Reform Act of 1986 and its impact on local construction, it provides statistical analysis of the effects of the Tax reform Act, it discusses innovative infrastructure financing techniques, finally federal infrastructure policy options.
Date: September 13, 1989
Creator: Graham, D. W. & Shinn, Paul L.
Partner: UNT Libraries Government Documents Department

Cooperative testing of a positive personnel identifier

Description: HEDL has a requirement to ensure the identification of remote computer terminal operators on a real-time nuclear inventory data base. The integrity of this data base depends on input from authorized individuals. Thus, a key to developing such a system is the ability to positively identify people attempting access to the system. Small scale tests of the Identimat 2000T hand geometry unit with an adjusting alogrithm have suggested a promising solution. To prove operational suitability, HEDL, in cooperation with Sandia Laboratories, has designed a large scale test of the Identimat 2000T. Data gathering on error rates, reliability, maintainability, and user acceptance will determine if the Identimat 2000T is suitable for the HEDL application. If proven acceptable, use of the Identimat 2000T can be broadened to many general applications where security information, locations and systems are required.
Date: June 1, 1980
Creator: O'Callaghan, P. B.; Grambihler, A. J.; Graham, D. K. & Bradley, R. G.
Partner: UNT Libraries Government Documents Department

Geochemical modeling of the Raft River geothermal field

Description: The results to date of chemical modeling of the Raft River KGRA are presented. Earlier work indicated a northwest-southeast anomaly in the contours. Modeling techniques applied to more complete data allowed further definition of the anomaly. Models described in this report show the source of various minerals in the geothermal water. There appears to be a regional heat source that gives rise to uniform conductive heat flow in the region, but convective flow is concentrated near the upwelling in the Crook well vicinity. Recommendations are made concerning field expansion and additional work needed to refine the overall reservoir model.
Date: November 1, 1979
Creator: Overton, H.L.; Chaney, R.E.; McAtee, R.E. & Graham, D.L.
Partner: UNT Libraries Government Documents Department

An Effective Theory of Dirac Dark Matter

Description: A stable Dirac fermion with four-fermion interactions to leptons suppressed by a scale {Lambda} {approx} 1 TeV is shown to provide a viable candidate for dark matter. The thermal relic abundance matches cosmology, while nuclear recoil direct detection bounds are automatically avoided in the absence of (large) couplings to quarks. The annihilation cross section in the early Universe is the same as the annihilation in our galactic neighborhood. This allows Dirac fermion dark matter to naturally explain the positron ratio excess observed by PAMELA with a minimal boost factor, given present astrophysical uncertainties. We use the Galprop program for propagation of signal and background; we discuss in detail the uncertainties resulting from the propagation parameters and, more importantly, the injected spectra. Fermi/GLAST has an opportunity to see a feature in the gamma-ray spectrum at the mass of the Dirac fermion. The excess observed by ATIC/PPB-BETS may also be explained with Dirac dark matter that is heavy. A supersymmetric model with a Dirac bino provides a viable UV model of the effective theory. The dominance of the leptonic operators, and thus the observation of an excess in positrons and not in anti-protons, is naturally explained by the large hypercharge and low mass of sleptons as compared with squarks. Minimizing the boost factor implies the right-handed selectron is the lightest slepton, which is characteristic of our model. Selectrons (or sleptons) with mass less than a few hundred GeV are an inescapable consequence awaiting discovery at the LHC.
Date: June 11, 2010
Creator: Harnik, Roni & Kribs, Graham D.
Partner: UNT Libraries Government Documents Department

EXTRACTION OF HIGHLY CHARGED AU IONS FROM A MULTIAMPHERE ELECTRON BEAM EBIS AT BNL.

Description: Excellent progress has been made in the operation of the BNL Electron Beam Ion Source (EBIS), which is a prototype for an EBIS that could meet requirements for a RHIC preinjector. We have achieved very stable operation of the electron beam at 10 A through the EBIS trap. Ion injection of low charge gold ions from a LEVA [1] ion source and subsequent extraction of these ions with most probable charge state AU{sup 34+} has been demonstrated with electron beams up to 8A. The total ion charge for gold measured on current transformer at the EBIS exit was 55nC after a 30ms confinement period. This corresponds to {approx}85% of the theoretical ion trap capacity and exceeds our goal of 50% neutralization. The collected ion charge is proportional to the electron current and the gold charge state scales with the electron current density. Details of the EBIS configuration, total charge measurements, and TOF spectra are given.
Date: September 2, 2001
Creator: BEEBE,E.N.; ALESSI,J.G.; GOULD,O.; GRAHAM,D.; KPONOU,A.; PIKIN,A. et al.
Partner: UNT Libraries Government Documents Department

Laboratory setup and results of experiments on two-dimensional multiphase flow in porous media

Description: In the event of an accidental release into earth's subsurface of an immiscible organic liquid, such as a petroleum hydrocarbon or chlorinated organic solvent, the spatial and temporal distribution of the organic liquid is of great interest when considering efforts to prevent groundwater contamination or restore contaminated groundwater. An accurate prediction of immiscible organic liquid migration requires the incorporation of relevant physical principles in models of multiphase flow in porous media; these physical principles must be determined from physical experiments. This report presents a series of such experiments performed during the 1970s at the Swiss Federal Institute of Technology (ETH) in Zurich, Switzerland. The experiments were designed to study the transient, two-dimensional displacement of three immiscible fluids in a porous medium. This experimental study appears to be the most detailed published to date. The data obtained from these experiments are suitable for the validation and test calibration of multiphase flow codes. 73 refs., 140 figs.
Date: October 1, 1990
Creator: McBride, J.F. (ed.) (Pacific Northwest Lab., Richland, WA (USA)); Graham, D.N. (ed.) & Schiegg, H.O. (SIMULTEC Ltd., Meilen/Zurich (Switzerland))
Partner: UNT Libraries Government Documents Department