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CP VIOLATION HIGHLIGHTS: CIRCA 2005 (open access)

CP VIOLATION HIGHLIGHTS: CIRCA 2005

Recent highlights in CP violation phenomena, are reviewed. B-factory results imply that, CP-violation phase in the CKM matrix is the dominant contributor to the observed CP violation in K and B-physics. Deviations from the predictions of the CKM-paradigm due to beyond the Standard Model CP-odd phase are likely to be a small perturbation. Therefore, large data sample of clean B's will be needed. Precise determination of the unitarity triangle, along with time dependent CP in penguin dominated hadronic and radiative modes are discussed. Null tests in B, K and top-physics and separate determination of the K-unitarity triangle are also emphasized.
Date: February 27, 2005
Creator: A., SONI
System: The UNT Digital Library
THE PHENIX EXPERIMENT AT RHIC. (open access)

THE PHENIX EXPERIMENT AT RHIC.

PHENIX is a large detector at the Relativistic Heavy Ion Collider (RHIC) at BNL. RHIC and PHENIX have recently operated for the first time, producing and detecting collisions of gold ions at beam energies of 30 and 65 GeV per nucleon. The current performance and future plans of PHENIX and of RHIC are presented.
Date: July 27, 2000
Creator: ARONSON,S. FOR THE PHENIX COLLABORATION
System: The UNT Digital Library
DETERMINING THE RATIO OF THE H+ YIELDS TV TO H+ YIELDS TB DECAY RATES FOR LARGE TAN BETA AT THE LARGE HADRON COLLIDER. (open access)

DETERMINING THE RATIO OF THE H+ YIELDS TV TO H+ YIELDS TB DECAY RATES FOR LARGE TAN BETA AT THE LARGE HADRON COLLIDER.

We present results on the determination of the observable ratio R = BR(H{sup +} {yields} {tau}{sup +}{nu}{sup -})/BR(H{sup +} {yields} t{bar b}) of charged Higgs boson decay rates as a discriminant quantity between Supersymmetric and non-Supersymmetric models. Simulation of measurements of this quantity through the analysis of the charged Higgs production process gb {yields} tbH{sup +} and relative backgrounds in the two above decay channels has been performed in the context of ATLAS. A {approx} 12-14% accuracy on R can be achieved for tan {beta} = 50, m{sub H{sup {+-}}} = 300-500 GeV and after an integrated luminosity of 300 fb{sup -1}. With this precision measurement, the Large Hadron Collider (LHC) can easily discriminate between models for the two above scenarios, so long as tan {beta} > 20.
Date: May 27, 2003
Creator: ASSAMAGAN,K. A. GUASCH,J. MORETTI,S. PENARANDA,S.
System: The UNT Digital Library
Management and Retrieval of Historical Nuclear Waste Previously Prepared and Concreted for Sea Disposal (open access)

Management and Retrieval of Historical Nuclear Waste Previously Prepared and Concreted for Sea Disposal

This paper describes the approach of dealing with an historic legacy of pharmaceutical manufacturing operations, which arose as a result of the temporary cessation of sea disposal in 1983. The result of that cessation was an accumulation of 1,000 reinforced concrete lined steel drums containing intermediate level nuclear waste of mixed chemical and physical form. Included are the steps taken which established a policy, the resulting strategy and the unique and innovative means by which the plan was implemented. The objective was to reduce the financial liability of the waste contained within the drums by removing those portions that had already decayed, segregating the waste in terms of non disposable and disposable isotopes, size reduction and long-term storage of the residues in a retrievable waste form. As part of this process the Company established a UK strategy which would ensure that the Company was self sufficient in radioactive waste handling storage facilities until the provision of a national facility, currently predicted to be approximately 2040.
Date: February 27, 2002
Creator: Abbott, H. & Davies, E.
System: The UNT Digital Library
The Framework for Approximate Queries on Simulation Data (open access)

The Framework for Approximate Queries on Simulation Data

AQSim is a system intended to enable scientists to query and analyze a large volume of scientific simulation data. The system uses the state of the art in approximate query processing techniques to build a novel framework for progressive data analysis. These techniques are used to define a multi-resolution index, where each node contains multiple models of the data. The benefits of these models are two-fold: (1) they are compact representations, reconstructing only the information relevant to the analysis, and (2) the variety of models capture different aspects of the data which may be of interest to the user but are not readily apparent in their raw form. To be able to deal with the data interactively, AQSim allows the scientist to make an informed tradeoff between query response accuracy and time. In this paper, we present the framework of AQSim with a focus on its architectural design. We also show the results from an initial proof-of-concept prototype developed at LLNL. The presented framework is generic enough to handle more than just simulation data.
Date: September 27, 2001
Creator: Abdulla, G.; Baldwin, C.; Critchlow, T.; Kamimura, R.; Lee, B.; Musick, R. et al.
System: The UNT Digital Library
The Dissociation Enthalpies of Terminal (N--O) Bonds in Organic Compounds (open access)

The Dissociation Enthalpies of Terminal (N--O) Bonds in Organic Compounds

Article on the dissociation enthalpies of terminal (N-O) bonds in organic compounds.
Date: May 27, 2005
Creator: Acree, William E. (William Eugene); Pilcher, Geoffrey & Silva, Maria D. M. C. Ribeiro da
System: The UNT Digital Library
Computational Modeling of K-shell Argon Spectra from Z-pinch Dynamic Hohlraum Experiments (open access)

Computational Modeling of K-shell Argon Spectra from Z-pinch Dynamic Hohlraum Experiments

Z-pinch dynamic hohlraum experiments on the Z-Machine at Sandia National Laboratories measured K-shell argon spectra using a focusing spectrometer with spatial resolution. The spectra are modeled using Hullac atomic data input, Cretin nonlocal thermodynamic equilibrium (nlte) atomic kinetics and radiative transfer calculations, and Dakota optimization capabilities. Hullac provides atomic structure and cross section data for Ar XIX, Ar XXVIII (n=1 (illegible) 5), Ar XXVII (n=1 (illegible) 10), and Ar XXVI (n=1 (illegible) 5), where n is the principal quantum number. Cretin calculates the area-integrated spectral intensity escaping an argon doped Dcapsule as a function of electron density, electron temperature, and capsule radius. Dakota optimizes the plasma properties for the best to the measured spectrum by minimizing an objective function comprise of argon spectral line ratios and full-width at half-maximums (fwhms). We highlight the framework of this general spectroscopic capability and discuss the extension to magnetized plasmas using Totalb spectral line shapes.
Date: October 27, 2004
Creator: Adams, M L; Sinars, D B; Scott, H A; Brandon, S T; Chung, H K & Lee, R W
System: The UNT Digital Library
Building Material Characterization Using a Concrete Floor and Wall Contamination Profiling Technology (open access)

Building Material Characterization Using a Concrete Floor and Wall Contamination Profiling Technology

Certain radioisotopes can penetrate concrete and contaminate the concrete well below the surface. The challenge is to determine the extent and magnitude of the contamination problem in real-time. The concrete profiling technology, TRUPROSM in conjunction with portable radiometric instrumentation produces a profile of radiological or chemical contamination through the material being studied. The data quality, quantity, and representativeness may be used to produce an activity profile from the hot spot surface into the material being sampled. This activity profile may then be expanded to ultimately characterize the facility and expedite waste segregation and facility closure at a reduced cost and risk. Performing a volumetric concrete or metal characterization safer and faster (without lab intervention) is the objective of this characterization technology. This way of determining contamination can save considerable time and money. Currently, concrete core bores are shipped to certified laboratories where the concrete residue is run through a battery of tests to determine the contaminants. The existing core boring operation volatilizes or washes out some of the contaminants (like tritium) and oftentimes cross-contaminates the area around the core bore site. The volatilization of the contaminants can lead to airborne problems in the immediate vicinity of the core bore. Cross-contamination …
Date: February 27, 2003
Creator: Aggarwal, S.; Charters, G. & Thacker, D.
System: The UNT Digital Library
A PYY Q62P variant linked to human obesity (open access)

A PYY Q62P variant linked to human obesity

Members of the pancreatic polypeptide family and the irreceptors have been implicated in the control of food intake in rodents and humans. To investigate whether nucleotide changes in these candidate genes result in abnormal weight in humans, we sequenced the coding exons and splice sites of seven family members (NPY, PYY, PPY, NPY1R, NPY2R, NPY4R, and NPY5R) in a large cohort of extremely obese (n=379) and lean (n=378) individuals. In total we found eleven rare non-synonymous variants, four of which exhibited familial segregation, NPY1R L53P and PPY P63L with leanness and NPY2R D42G and PYY Q62P with obesity. Functional analysis of the obese variants revealed NPY2R D42G to have reduced cell surface expression, while previous cell culture based studies indicated variant PYY Q62P to have altered receptor binding selectivity and we show that it fails to reduce food intake through mouse peptide injection experiments. These results support that rare non-synonymous variants within these genes can alter susceptibility to human body mass index extremes.
Date: June 27, 2005
Creator: Ahituv, Nadav; Kavaslar, Nihan; Schackwitz, Wendy; Ustaszewska,Anna; Collier, John Michael; Hebert, Sybil et al.
System: The UNT Digital Library
Commercial Application of Plasma Mass Separation in the Archimedes Filter Plant (open access)

Commercial Application of Plasma Mass Separation in the Archimedes Filter Plant

This paper describes the commercial application of an innovative plasma mass separator called the Archimedes Filter to a pre-treatment plant that can be integrated into the U.S. Department of Energy (DOE) Hanford and Savannah River Sites to significantly enhance the treatment of radioactive high-level waste. The output of the Archimedes Filter is completely compatible with existing waste immobilization processes such as vitrification and requires no new waste form to be developed. A full-geometric-scale Demonstration Filter Unit (DEMO) has been constructed and is undergoing initial testing at the Archimedes Technology Group Development Facilities in San Diego. Some of the technology and engineering development is being performed by other organizations in collaboration with Archimedes. The Commissariat a l'Energie Atomique (CEA) is developing the plasma calcination technology and all of the associated systems for AFP feed preparation. Two Russian institutes are involved in the development of the ICP torch and injector system. The Remote System Group (UT-Battelle) at ORNL is developing the remote maintenance system for the filter units. Conceptual design of the Archimedes Filter Plant (AFP) is being developed concurrently with the DEMO testing program. The AFP mission is to significantly reduce the cost and accelerate the rate of vitrification of high-level …
Date: February 27, 2003
Creator: Ahlfeld, C.E.; Gilleland, J.G. & Wagoner, J.D.
System: The UNT Digital Library
Binary Microlensing Events from the MACHO Project (open access)

Binary Microlensing Events from the MACHO Project

This article presents the light curves of 21 gravitational microlensing events from the first six years of the MACHO Project gravitational microlensing survey that are likely examples of lensing by binary systems.
Date: March 27, 2000
Creator: Alcock, C.; Allsman, R. A.; Alves, D.; Axelrod, T. S.; Baines, D.; Becker, A. C. et al.
System: The UNT Digital Library
Bulk Properties of Iron Isotopes (open access)

Bulk Properties of Iron Isotopes

Nuclear level densities and radiative strength functions (RSF) in {sup 56}Fe and {sup 57}Fe were measured using the {sup 57}Fe({sup 3}He,{alpha}{gamma}) and {sup 57}Fe({sup 3}He, {sup 3}He{prime}{gamma}) reactions, respectively, at Oslo Cyclotron Laboratory. A low-energy enhancement in the RSF below 4 MeV energy was observed. This finding cannot be explained by common theoretical models. In a second experiment, two-step cascade intensities with soft primary transitions from the {sup 56}Fe(n,2{gamma}) reaction were measured. The agreement between the two experiments confirms the low-energy enhancement in the RSF. In a third experiment, the neutron evaporation spectrum from the {sup 55}Mn(dn,N){sup 56}Fe reaction was measured at 7-MeV deuteron energy at John Edwards Accelerator Laboratory at Ohio University. Comparison of the level density of {sup 56}Fe obtained from the first and third experiments gives an overall good agreement. Furthermore, observed enhancement for soft {gamma} rays is supported by the last experiment.
Date: July 27, 2006
Creator: Algin, E.; Schiller, A.; Voinov, A.; Agvannluvsan, U.; Belgya, T.; Bernstein, L. et al.
System: The UNT Digital Library
Renewal, Modulation, and Superstatistics in Times Series (open access)

Renewal, Modulation, and Superstatistics in Times Series

Article discussing two different approaches, referred to as renewal and modulation, to generate time series with a nonexponential distribution of waiting times.
Date: April 27, 2006
Creator: Allegrini, Paolo; Barbi, Francesco; Grigolini, Paolo & Paradisi, Paolo
System: The UNT Digital Library
ASHTABULA SUCCESSES--MACRO NOW OR FOREVER HOLD YOUR PIECES! (open access)

ASHTABULA SUCCESSES--MACRO NOW OR FOREVER HOLD YOUR PIECES!

As facility demolition and remediation continued at the DOE Ashtabula Environmental Management Project (AEMP), a DOE closure site located in Ashtabula, OH, the quantity of mixed waste increased by approximately twenty-fold from the original Site Treatment Plan estimates to over 567 m3 (20,000 cubic feet). Also, a greater variety of low-level mixed waste (MW) was identified that was suitable for alternate debris treatment like macroencapsulation (MACRO) instead of traditional shredding, stabilization, and solidification to improve the overall safety and cost-effectiveness. Macroencapsulation is required for lead and authorized for hazardous debris under the alternate debris treatment standards per 40 CFR 268.45. Several polymer encapsulation processes were being explored, developed, and deployed in the mid-1990's by various groups including the DOE Mixed Waste Focus Area, DOE EM-50 Office of Science and Technology, Brookhaven National Laboratory, DOE Macro Working Group, DOE-Albuquerque Mixed Waste/Mobile Treatment Unit, and Envirocare of Utah, Inc. As a result, technically-proven macroencapsulation and microencapsulation processes using extruded polyethylene beads were verified as being technically acceptable for waste treatment to RCRA standards. The AEMP had a variety of waste forms where technically-proven systems were needed to perform on-site treatment of challenging mixed wastes (MW) from production operations (i.e. HEPA filters, barium …
Date: February 27, 2003
Creator: Altmayer, S. A.; Forschner, J. A.; Kulpa, J. P. & Spoerner, M. T.
System: The UNT Digital Library
LARP Long Nb3Sn Quadrupole Design. (open access)

LARP Long Nb3Sn Quadrupole Design.

A major milestone for the LHC Accelerator Research Program (LARP) is the test, by the end of 2009, of two 4m-long quadrupole magnets (LQ) wound with Nb{sub 3}Sn conductor. The goal of these magnets is to be a proof of principle that Nb{sub 3}Sn is a viable technology for a possible LHC luminosity upgrade. The design of the LQ is based on the design of the LARP Technological Quadrupoles, presently under development at FNAL and LBNL, with 90-mm aperture and gradient higher than 200 T/m. The design of the first LQ model will be completed by the end of 2007 with the selection of a mechanical design. In this paper we present the coil design addressing some fabrication technology issues, the quench protection study, and three designs of the support structure.
Date: August 27, 2007
Creator: Ambrosio, G.; Andreev, N.; Anerella, M.; Barzi, E.; Bossert, R.; Caspi, S. et al.
System: The UNT Digital Library
The fractal nature of vacuum arc cathode spots (open access)

The fractal nature of vacuum arc cathode spots

Cathode spot phenomena show many features of fractals, for example self-similar patterns in the emitted light and arc erosion traces. Although there have been hints on the fractal nature of cathode spots in the literature, the fractal approach to spot interpretation is underutilized. In this work, a brief review of spot properties is given, touching the differences between spot type 1 (on cathodes surfaces with dielectric layers) and spot type 2 (on metallic, clean surfaces) as well as the known spot fragment or cell structure. The basic properties of self-similarity, power laws, random colored noise, and fractals are introduced. Several points of evidence for the fractal nature of spots are provided. Specifically power laws are identified as signature of fractal properties, such as spectral power of noisy arc parameters (ion current, arc voltage, etc) obtained by fast Fourier transform. It is shown that fractal properties can be observed down to the cutoff by measurement resolution or occurrence of elementary steps in physical processes. Random walk models of cathode spot motion are well established: they go asymptotically to Brownian motion for infinitesimal step width. The power spectrum of the arc voltage noise falls as 1/f {sup 2}, where f is frequency, …
Date: May 27, 2005
Creator: Anders, Andre
System: The UNT Digital Library
Fundamentals of pulsed plasmas for materials processing (open access)

Fundamentals of pulsed plasmas for materials processing

None
Date: April 27, 2003
Creator: Anders, Andre
System: The UNT Digital Library
Time-dependence ion charge state distributions of vacuum arcs: An interpretation involving atoms and charge exchange collisions (open access)

Time-dependence ion charge state distributions of vacuum arcs: An interpretation involving atoms and charge exchange collisions

Experimentally observed charge state distributions are known to be higher at the beginning of each arc discharge. Up to know, this has been attributed to cathode surface effects in terms of changes of temperature, chemical composition and spot mode. Here it is shown that the initial decay of charge states of cathodic arc plasmas may at least in part due to charge exchange collisions of ions with neutrals that gradually fill the discharge volume. Sources of neutrals may include evaporated atoms from macroparticles and still-hot craters of previously active arc spots. More importantly, atoms are also produced by energetic condensation of the cathodic arc plasma. Self-sputtering is significant when ions impact with near-normal angle of incidence, and ions have low sticking probability when impacting at oblique angle of incidence. Estimates show that the characteristic time for filling the near-cathode discharge volume agrees well with the charge state decay time, and the likelihood of charge exchange is reasonably large to be taken into account.
Date: August 27, 2004
Creator: Anders, Andre
System: The UNT Digital Library
Experience with Dismantling of the Analytic Cell in the JRTF Decommissioning Program (open access)

Experience with Dismantling of the Analytic Cell in the JRTF Decommissioning Program

The analytic cell was mainly used for process control analysis of the reprocessing process and for the measurement of fuel burn up ratio in JAERI's Reprocessing Test Facility (JRTF). The analytic cell was a heavy shielded one and equipped with a conveyor. The cell was alpha and beta(gamma)contaminated. For dismantling of analytic cells, it is very important to establish a method to remove the heavy shield safely and reduce the exposure. At first, a green house was set up to prevent the spread out of contamination, and next, the analytic cell was dismantled. Depending on the contamination condition, the workers wore protective suits such as air ventilated-suits for prevention of internal exposure and vinyl chloride aprons, lead aprons in order to reduce external exposure. From the work carried out, various data such as needed manpower for the activities, the collective dose of workers by external exposure, the amount of radioactive wastes and the relation between the weight of the shield and its dismantling efficiency were obtained and input for the database. The method of dismantling and the experience with the dismantling of the analytic cell in the JRTF, carried out during 2001 and 2002, are described in this paper.
Date: February 27, 2003
Creator: Annoh, Akio; Nemoto, Koichi; Tajiri, Hideo; Saito, Keiichiro; Miyajima, Kazutoshi & Myodo, Masato
System: The UNT Digital Library
Evaluation of Management Routes for the Paldiski Sarcophagi (open access)

Evaluation of Management Routes for the Paldiski Sarcophagi

The necessity to develop the submarine fleet in Russia required constructing a special training base for the training of submarine crews. To this purpose two prototypes of nuclear power units, close analogous to those fitting out nuclear submarines were constructed and commissioned in the sixties on the Navy training centre's base located in Paldiski (Pakri peninsula, Estonia). In 1994, nuclear fuel was discharged from the reactors and transported to Russia while the reactors themselves were prepared for prolonged storage, prior to transfer of the Paldiski facilities to the ownership of the Estonian Republic. The Paldiski facilities are currently being dismantled with the exception of two sarcophagi made of concrete that are housing the two reactor compartments. The question of the future management of both sarcophagi is a key-issue in the cleaning up of the whole Paldiski site. Actually, three basic questions should answered: when should dismantling operations occur, how this should be done, and what could be the corresponding cost. Within the context of enlargement of the European Union, the Commission services (first Directorate-General for Environment and then Directorate-General for Enlargement) decided to support Estonia to respond to these three questions through a study contract that was awarded in 1999 …
Date: February 27, 2002
Creator: Antonel, L.; Robin, B.; Miller, J. W.; Putnik, H. & Simanovski, Y.
System: The UNT Digital Library
The 2mrad horizontal crossing angle IR layout for a TeV ILC (open access)

The 2mrad horizontal crossing angle IR layout for a TeV ILC

The current status of the 2mrad crossing angle layout for the ILC is reviewed. The scheme developed in the UK and France is described and the performance discussed for a TeV machine. Secondly, the scheme developed at SLAC and BNL is then studied and modified for a TeV machine. We find that both schemes can handle the higher energy beam with modifications, and share many common features.
Date: July 27, 2005
Creator: Appleby, R.; Angal-Kalinin, D.; /Daresbury; Bambade, P.; Mouton, B.; /Orsay, LAL et al.
System: The UNT Digital Library
Proposal of the Next Incarnation of Accelerator Test Facility at KEK for the International Linear Collider (open access)

Proposal of the Next Incarnation of Accelerator Test Facility at KEK for the International Linear Collider

To reach design luminosity, the International Linear Collider (ILC) must be able to create and reliably maintain nanometer size beams. The ATF damping ring is the unique facility where ILC emittances are possible. In this paper we present and evaluate the proposal to create a final focus facility at the ATF which, using compact final focus optics and an ILC-like bunch train, would be capable of achieving 37 nm beam size. Such a facility would enable the development of beam diagnostics and tuning methods, as well as the training of young accelerator physicists.
Date: May 27, 2005
Creator: Araki, S.; Hayano, H.; Higashi, Y.; Honda, Y.; Kanazawa, K.; Kubo, K. et al.
System: The UNT Digital Library
Small Neutrino Masses from Supersymmetry Breaking (open access)

Small Neutrino Masses from Supersymmetry Breaking

An alternative to the conventional see-saw mechanism is proposed to explain the origin of small neutrino masses in supersymmetric theories. The masses and couplings of the right-handed neutrino field are suppressed by supersymmetry breaking, in a way similar to the suppression of the Higgs doublet mass, $\mu$. New mechanisms for light Majorana, Dirac and sterile neutrinos arise, depending on the degree of suppression. Superpartner phenomenology is greatly altered by the presence of weak scale right-handed sneutrinos, which may have a coupling to a Higgs boson and a left-handed sneutrino. The sneutrino spectrum and couplings are quite unlike the conventional case - the lightest sneutrino can be the dark matter and predictions are given for event rates at upcoming halo dark matter direct detection experiments. Higgs decays and search strategies are changed. Copious Higgs production at hadron colliders can result from cascade decays of squarks and gluinos.
Date: June 27, 2000
Creator: Arkani-Hamed, Nima; Hall, Lawrence; Murayama, Hitoshi; Smith, David & Weiner, Neal
System: The UNT Digital Library
A HIGH CURRENT, HIGH VOLTAGE SOLID-STATE PULSE GENERATOR FOR THE NIF PLASMA ELECTRODE POCKELS CELL (open access)

A HIGH CURRENT, HIGH VOLTAGE SOLID-STATE PULSE GENERATOR FOR THE NIF PLASMA ELECTRODE POCKELS CELL

A high current, high voltage, all solid-state pulse modulator has been developed for use in the Plasma Electrode Pockels Cell (PEPC) subsystem in the National Ignition Facility. The MOSFET-switched pulse generator, designed to be a more capable plug-in replacement for the thyratron-switched units currently deployed in NIF, offers unprecedented capabilities including burst-mode operation, pulse width agility and a steady-state pulse repetition frequency exceeding 1 Hz. Capable of delivering requisite fast risetime, 17 kV flattop pulses into a 6 {Omega} load, the pulser employs a modular architecture characteristic of the inductive adder technology, pioneered at LLNL for use in acceleration applications, which keeps primary voltages low (and well within the capabilities of existing FET technology), reduces fabrication costs and is amenable to rapid assembly and quick field repairs.
Date: July 27, 2007
Creator: Arnold, P. A.; Barbosa, F.; Cook, E. G.; Hickman, B. C.; Akana, G. L. & Brooksby, C. A.
System: The UNT Digital Library