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Corporate Tax Rates and the Purchasing Power Parity Doctrine

Description: This thesis analyzes the effect of corporate tax rates on the purchasing-power-parity (PPP) doctrine. The data used to test this hypothesis are drawn from the U. S., the U. K., the Federal Republic of Germany, Canada, and Japan. The first chapter introduces the reader to the concepts of the PPP doctrine and states the hypothesis. Chapter 2 reviews the literature on the PPP doctrine. Chapter 3 specifies a model of the PPP doctrine including tax rates. Chapter 4 reports and interprets the findings. The study is summarized and conclusions are drawn in chapter 5. In this study it is shown that tax rates are significant only in the case of the U. S. dollar/Canadian dollar exchange rate.
Date: August 1988
Creator: Ballard, Billy L. (Billy Lanoy)
Partner: UNT Libraries

Purchasing Power Parity and the Efficient Markets: the Recent Empirical Evidence

Description: The purpose of the study is to empirically determine the relevance of PPP theory under the traditional arbitrage and the efficient markets (EPPP) frameworks during the recent floating period of the 1980s. Monthly data was collected for fifteen industrial nations from January 1980 to December 1986. The models tested included the short-run PPP, the long-run PPP, the EPPP, the EPPP with deviations from expectations, the forward rates as unbiased estimators of future spot rates, the EPPP and the forward rates, and the EPPP with forward rates and lagged values. A generalized regression method called Seemingly Unrelated Regression (SUR) was employed to test the models. The results support the efficient markets approach to PPP but fail to support the traditional PPP in both the short term and the long term. Moreover, the forward rates are poor and biased predictors of the future spot rates. The random walk hypothesis is generally supported.
Date: December 1988
Creator: Yuyuenyongwatana, Robert P. (Robert Privat)
Partner: UNT Libraries

Azimuthal Charged-Particle Correlations and Possible Local Strong Parity Violation

Description: Parity-odd domains, corresponding to non-trivial topological solutions of the QCD vacuum, might be created during relativistic heavy-ion collisions. These domains are predicted to lead to charge separation of quarks along the system's orbital momentum axis. We investigate a three particle azimuthal correlator which is a {Rho} even observable, but directly sensitive to the charge separation effect. We report measurements of charged hadrons near center-of-mass rapidity with this observable in Au+Au and Cu+Cu collisions at {radical}s{sub NN} = 200 GeV using the STAR detector. A signal consistent with several expectations from the theory is detected. We discuss possible contributions from other effects that are not related to parity violation.
Date: July 5, 2010
Creator: Collaboration, STAR & Abelev, Betty
Partner: UNT Libraries Government Documents Department

A Convergence of LDPC Based on Eigenvalues

Description: Low-density parity check (LDPC) codes are very popular among error correction codes because of their high-performance capacity. Numerous investigations have been carried out to analyze the performance and simplify the implementation of LDPC codes. Relatively slow convergence of iterative decoding algorithm affects the performance of LDPC codes. Faster convergence can be achieved by reducing the number of iterations during the decoding process. In this thesis, a new approach for faster convergence is suggested by choosing a systematic parity check matrix that yields lowest Second Smallest Eigenvalue Modulus (SSEM) of its corresponding Laplacian matrix. MATLAB simulations are used to study the impact of eigenvalues on the number of iterations of the LDPC decoder. It is found that for a given (n, k) LDPC code, a parity check matrix with lowest SSEM converges quickly as compared to the parity check matrix with high SSEM. In other words, a densely connected graph that represents the parity check matrix takes more iterations to converge than a sparsely connected graph.
Date: August 2017
Creator: Kharate, Neha Ashok
Partner: UNT Libraries

Excitations of the nucleon with dynamical fermions

Description: We measure the spectrum of low-lying nucleon resonances using Bayesian fitting methods. We compare the masses obtained in the quenched approximation to those obtained with two flavours of dynamical fermions at a matched lattice spacing. At the pion masses employed in our simulations, we find that the mass of the first positive-parity nucleon excitation is always greater than that of the parity partner of the nucleon.
Date: June 1, 2002
Creator: Maynard, C.M. & Richards, D.G.
Partner: UNT Libraries Government Documents Department

Exotic Mesons, Theory and Experiment

Description: In this talk I summarize the status of exotic mesons, including both theoretical expectations and experimental candidates. The current experimental candidates are ''spin-parity exotics'', since these are most often considered possible hybrid mesons, the theoretical discussion will be mainly concerned with hybrids. The exotic meson candidates discussed are the surprisingly light {pi}{sub 1} (1400) and {pi}{sub 1} (1600).
Date: April 26, 2001
Creator: Barnes, T.
Partner: UNT Libraries Government Documents Department

PNC in hydrogen. different prospects using heliumlike ions.

Description: The motivation for parity experiments in simple atomic systems is that the atomic physics is known precisely so they directly test the weak interactions. We review the status of the parity experiments that have been done in atomic hydrogen and suggest some possibilities for experiments in helium like ions.
Date: September 25, 1998
Creator: Dunford, R. W.
Partner: UNT Libraries Government Documents Department

R-Parity From the Heterotic String

Description: In T-duality invariant effective supergravity with gaugino condensation as the mechanism for supersymmetry breaking, there is a residual discrete symmetry that could play the role of R-parity in supersymmetric extensions of the Standard Model.
Date: December 7, 2004
Creator: Gaillard, Mary K.
Partner: UNT Libraries Government Documents Department

Grid Parity for Residential Photovoltaics in the United States: Key Drivers and Sensitivities; Preprint

Description: In this report, we analyze PV break-even costs for U.S. residential customers. We evaluate some key drivers of grid parity both regionally and over time. We also examine the impact of moving from flat to time-of-use (TOU) rates, and we evaluate individual components of the break-even cost, including effect of rate structure and various incentives. Finally, we examine how PV markets might evolve on a regional basis considering the sensitivity of the break-even cost to four major drivers: technical performance, financing parameters, electricity prices and rates, and policies. We find that electricity price rather than technical parameters are in general the key drivers of the break-even cost of PV. Additionally, this analysis provides insight about the potential viability of PV markets.
Date: August 1, 2012
Creator: Ong, S.; Denholm, P. & Clark, N.
Partner: UNT Libraries Government Documents Department

Break-Even Cost for Residential Photovoltaics in the United States: Key Drivers and Sensitivities

Description: Grid parity--or break-even cost--for photovoltaic (PV) technology is defined as the point where the cost of PV-generated electricity equals the cost of electricity purchased from the grid. Break-even cost is expressed in $/W of an installed system. Achieving break-even cost is a function of many variables. Consequently, break-even costs vary by location and time for a country, such as the United States, with a diverse set of resources, electricity prices, and other variables. In this report, we analyze PV break-even costs for U.S. residential customers. We evaluate some key drivers of grid parity both regionally and over time. We also examine the impact of moving from flat to time-of-use (TOU) rates, and we evaluate individual components of the break-even cost, including effect of rate structure and various incentives. Finally, we examine how PV markets might evolve on a regional basis considering the sensitivity of the break-even cost to four major drivers: technical performance, financing parameters, electricity prices and rates, and policies. We find that local incentives rather than ?technical? parameters are in general the key drivers of the break-even cost of PV. Additionally, this analysis provides insight about the potential viability of PV markets.
Date: December 1, 2009
Creator: Denholm, P.; Margolis, R. M.; Ong, S. & Roberts, B.
Partner: UNT Libraries Government Documents Department

Dynamic Stark effect and forbidden-transition spectrallineshapes

Description: We report on an experimental and theoretical study of thedynamic (ac) Stark effect on a for bidden transition. A general frameworkfor parameterizing and describing off-resonant ac-Stark shifts ispresented. A model is developed to calculate spectral line shapesresulting from resonant excitation of atoms in an intense standinglight-wave in the presence of off-resonant ac-Stark shifts. The model isused in the analysis and interpretation of a measurement of the ac-Starkshifts of the static-electric-field-induced 6s2 1S0 -->5d6s 3D1transition at 408 nm in atomic Yb. The results are in agreement withestimates of the ac-Stark shift of the transition under the assumptionthat the shift is dominated by that of the 6s2 1S0 ground state. Adetailed description of the experiment and analysis is presented. Abi-product of this work is an ind ependent determination (from thesaturation behavior of the 408-nm transition) of the Stark transitionpolarizability, which is found to be in agreement with our earliermeasurement. This work is part of the ongoing effort aimed at a precisionmeasurement of atomic parity-violation effects in Yb.
Date: December 15, 2005
Creator: Stalnaker, Jason E.; Budker, D.; Freedman, S.J.; Guzman, J.S.; Rochester, S.M. & Yashchuk, V.V.
Partner: UNT Libraries Government Documents Department

Meson-meson scattering: K{anti K}-thresholds and f{sub 0}(980)-a{sub 0}(980) mixing

Description: The authors study the influence of mass splitting between the charged and neutral pions and kaons in the Juelich meson exchange model for {pi}{pi} and {pi}{eta} scattering. The calculations are performed in the particle basis, which permits the use of physical masses for the pseudoscalar mesons and a study of the distinct thresholds associated with the neutral and the charged kaons. Within this model the authors also investigate the isospin violation which arises from the mass splitting and an apparent violation of G-parity in {pi}{pi} scattering which stems from the coupling to the K{anti K} channel. Nonvanishing cross sections for {pi}{pi} {r_arrow} {pi}{sup 0}{eta} indicate a mixing of the f{sub 0}(980) and a{sub 0}(980) states.
Date: September 1, 1996
Creator: Krehl, O.; Rapp, R. & Speth, J.
Partner: UNT Libraries Government Documents Department

Quadratic electroweak corrections for polarized Moller scattering

Description: The paper discusses the two-loop (NNLO) electroweak radiative corrections to the parity violating electron-electron scattering asymmetry induced by squaring one-loop diagrams. The calculations are relevant for the ultra-precise 11 GeV MOLLER experiment planned at Jefferson Laboratory and experiments at high-energy future electron colliders. The imaginary parts of the amplitudes are taken into consideration consistently in both the infrared-finite and divergent terms. The size of the obtained partial correction is significant, which indicates a need for a complete study of the two-loop electroweak radiative corrections in order to meet the precision goals of future experiments.
Date: January 1, 2012
Creator: A. Aleksejevs, S. Barkanova, Y. Kolomensky, E. Kuraev, V. Zykunov
Partner: UNT Libraries Government Documents Department

Contributions From yZ Box Diagrams to Parity Violating Elastic e-p Scattering

Description: Parity-violating (PV) elastic electron-proton scattering measures Q-weak for the proton, Q{sub W}{sup p}. To extract Q{sub W}{sup p} from data, all radiative corrections must be well-known. Recently, disagreement on the {gamma}Z box contribution to Q{sub W}{sup p} has prompted the need for further analysis of this term. Here, we support one choice of a debated factor, go beyond the previously assumed equality of electromagnetic and {gamma}Z structure functions, and find an analytic result for one of the {gamma}Z box integrals. Our numerical evaluation of the {gamma}Z box is in agreement within errors with previous reports, albeit somewhat larger in central value, and is within the uncertainty requirements of current experiments.
Date: June 1, 2011
Creator: Benjamin Rislow, Carl Carlson
Partner: UNT Libraries Government Documents Department

UPGRADING THE CEBAF INJECTOR WITH A NEW BOOSTER, HIGHER VOLTAGE GUN, AND HIGHER FINAL ENERGY

Description: The Continuous Electron Beam Accelerator Facility (CEBAF) accelerator at Jefferson Lab will be upgraded from 6 GeV to 12 GeV in the next few years. To meet the requirement of the new machine and to take the opportunity to improve the beam quality, the CEBAF injector will be upgraded with a higher voltage gun, a new booster, and a new accelerating RF module. The CEBAF injector creates and accelerates three beams at different currents simultaneously. The beams are interleaved, each at one third of the RF frequency, traveling through the same beam line. The higher voltage gun will lower the space charge effects. The new booster with optimized beam dynamics will complete the bunching process and provide initial acceleration matched to the new gun voltage. Using our latest SRF design, the new booster has significantly lower x/y coupling effects that should improve our beam setup and operation for the highly sensitive parity experiments scheduled for the CEBAF's future. Finally, the new accelerating RF module will roughly double the injector final energy to match the rest of the 12 GeV accelerator. In this paper we will provide more detail about this upgrade.
Date: July 1, 2012
Creator: Kazimi, Reza; Freyberger, Arne; Hofler, Alicia; Hutton, Andrew & Hannon, Fay
Partner: UNT Libraries Government Documents Department

THE Epsilon*/Lambda BRANCHING RATIO OF Y*1

Description: Recently a T = 1 resonance in the {Lambda}{pi} system called Y*{sub 1} has been observed with a mass of 1385 Mev. Two types of resonances have been predicted that might relate this observation to other elementary-particle interactions: (1) P 3/2 resonances in the {Lambda}{pi} and {Sigma}{pi} systems predicted by global symmetry corresponding to the (3/2, 3/2) resonance of the {pi}N system; (2) a spin-1/2 Y-{pi} resonance resulting from a bound state in the KN system. The position and width of the observed Y*{sub 1} resonance agree with both theories, but since the spin and parity have not yet been determined, it is impossible at present to distinguish between the two theoretical interpretations.
Date: April 25, 1961
Creator: Alston, Margaret H.; Alvarez, Luis W.; Eberhard, Philippe; Good,Myron L.; Graziano, William; Ticho, Harold K. et al.
Partner: UNT Libraries Government Documents Department

A STUDY OF RESONANCES OF THE Z-7r SYSTEM

Description: Recently a T = 1 resonance in the {Lambda}-{pi} system called Y{sub 1} has been observed with a mass of 1385 MeV. Two types of resonances have been predicted that might relate this observation to other elementary-particle interactions: (1) P 3/2 resonances in the {Lambda}-{pi} and {Sigma}-{pi} systems predicted by global symmetry, corresponding to the (3,2/ 3/2) resonance of the {pi}-N system, (2) a spin-1/2 Y-{pi} resonance resulting from a bound state in the {bar K}-N system. The position and the width of the observed Y{sub 1} resonance agree with both theories, but since the spin and parity have not yet been determined, they cannot distinguish between the two theoretical interpretations.
Date: May 23, 1961
Creator: Alston, M.H.; Alvarez, L.W.; Eberhard, P.; Good, M.L.; Graziano,W.; Ticho, H.K. et al.
Partner: UNT Libraries Government Documents Department

Natural Little Hierarchy from Partially Goldstone Twin Higgs

Description: We construct a simple theory in which the fine-tuning of the standard model is significantly reduced. Radiative corrections to the quadratic part of the scalar potential are constrained to be symmetric under a global U(4) x U(4){prime} symmetry due to a discrete Z{sub 2} 'twin' parity, while the quartic part does not possess this symmetry. As a consequence, when the global symmetry is broken the Higgs fields emerge as light pseudo-Goldstone bosons, but with sizable quartic self-interactions. This structure allows the cutoff scale, {Lambda}, to be raised to the multi-TeV region without significant fine-tuning. In the minimal version of the theory, the amount of fine-tuning is about 15% for {Lambda} = 5 TeV, while it is about 30% in an extended model. This provides a solution to the little hierarchy problem. In the minimal model, the 'visible' particle content is exactly that of the two Higgs doublet standard model, while the extended model also contains extra vector-like fermions with masses {approx} (1 {approx} 2) TeV. At the LHC, our minimal model may appear exactly as the two Higgs doublet standard model, and new physics responsible for cutting off the divergences of the Higgs mass-squared parameter may not be discovered. Several possible processes that may be used to discriminate our model from the simple two Higgs doublet model are discussed for the LHC and for a linear collider.
Date: October 20, 2005
Creator: Chacko, Z.; Nomura, Yasunori; Papucci, Michele & Perez, Gilad
Partner: UNT Libraries Government Documents Department

Parity Violation Workshop - CEBAF

Description: This paper discusses the use of electron scattering experiments for exploring parity violation in the nuclear domain. It is shown how such experiments can test the structure of strong interactions, the local gauge theory quantum chromodynamics based on color, and the unified gauge theory of electroweak interactions.
Date: December 1, 1986
Creator: Walecka, J.
Partner: UNT Libraries Government Documents Department

Parity Doubling and the S Parameter Below the Conformal Window

Description: We describe a lattice simulation of the masses and decay constants of the lowest-lying vector and axial resonances, and the electroweak S parameter, in an SU(3) gauge theory with N{sub f} = 2 and 6 fermions in the fundamental representation. The spectrum becomes more parity doubled and the S parameter per electroweak doublet decreases when N{sub f} is increased from 2 to 6, motivating study of these trends as N{sub f} is increased further, toward the critical value for transition from confinement to infrared conformality.
Date: October 21, 2011
Creator: Appelquist, T; Babich, R; Brower, R C; Cheng, M; Clark, M A; Cohen, S D et al.
Partner: UNT Libraries Government Documents Department

Measurement of the Strange Quark Contribution to Proton Structure through Parity Violating Electron-Proton Scattering

Description: The G0 (G-Zero) forward angle experiment completed in Hall C of the Thomas Jefferson National Accelerator Facility (TJNAF) has measured the parity violating asymmetries in elastic electron-proton scattering over a Q2 range of 0.12 < Q2 < 1.0 (GeV/c)2. A linear combination of the strange electric (GsE) and magnetic (GsM) form factors calculated from these asymmetries indicate a non-zero contribution of the strange quark to the charge and magnetization structure of the proton in the above kinematic range at a 89% confidence level. The results show a previously unmeasured Q2 dependence of the strange form factors. Combining the G0 results with previous parity violating experiments show that at Q2 = 0.1 (GeV/c)2 GsM = 0.62+-0.31 GsE = -0.013+-0.028 At intermediate Q2 of about 0.23 (GeV/c)2, a consistent value of GsM is seen compared to previous experiments, together with a measurement that may imply a negative value of GsE. For Q2 above 0.5 (GeV/c)2 a consistently positive value for the linear combination of the strange form factors is seen.
Date: May 1, 2006
Creator: Nakahara, Kazutaka
Partner: UNT Libraries Government Documents Department