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Proton hexality from an anomalous flavor U(1) and neutrino masses--Linking to the string scale

Description: We devise minimalistic gauged U(1)_X Froggatt-Nielsen models which at low-energy give rise to the recently suggested discrete gauge Z_6 symmetry, proton hexality, thus stabilizing the proton. Assuming three generations of right-handed neutrinos, with the proper choice of X-charges, we obtain viable neutrino masses. Furthermore, we find scenarios such that no X-charged hidden sector superfields are needed, which from a bottom-up perspective allows the calculation of g_string, g_X and G_SM's … more
Date: August 7, 2007
Creator: Murayama, Hitoshi; Dreiner, Herbi K.; Luhn, Christoph; Murayama, Hitoshi & Thormeiere, Marc
Partner: UNT Libraries Government Documents Department
open access

Relativistic Many-body Moller-Plesset Perturbation Theory Calculations of the Energy Levels and Transition Probabilities in Na- to P-like Xe Ions

Description: Relativistic multireference many-body perturbation theory calculations have been performed on Xe{sup 43+}-Xe{sup 39+} ions, resulting in energy levels, electric dipole transition probabilities, and level lifetimes. The second-order many-body perturbation theory calculation of energy levels included mass shifts, frequency-dependent Breit correction and Lamb shifts. The calculated transition energies and E1 transition rates are used to present synthetic spectra in the extreme ultraviolet range fo… more
Date: March 27, 2007
Creator: Vilkas, M J; Ishikawa, Y & Trabert, E
Partner: UNT Libraries Government Documents Department
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ANALYTICAL METHOD FOR MEASURING TOTAL PROTIUM AND TOTAL DEUTERIUM IN A GAS MIXTURE CONTAINING H2, D2,AND HD VIA GAS CHAROMATOGRAPHY

Description: The most common analytical method of identifying and quantifying non-radioactive isotopic species of hydrogen is mass spectrometry. A low mass, high resolution mass spectrometer with adequate sensitivity and stability to identify and quantify hydrogen isotopes in the low ppm range is an expensive, complex instrument. A new analytical technique has been developed that measures both total protium (H) and total deuterium (D) in a gas mixture containing H{sub 2}, D{sub 2}, and HD using an inexpensi… more
Date: August 7, 2007
Creator: Sessions, H
Partner: UNT Libraries Government Documents Department
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Analysis of the SL-1 Accident Using RELAPS5-3D

Description: On January 3, 1961, at the National Reactor Testing Station, in Idaho Falls, Idaho, the Stationary Low Power Reactor No. 1 (SL-1) experienced a major nuclear excursion, killing three people, and destroying the reactor core. The SL-1 reactor, a 3 MW{sub t} boiling water reactor, was shut down and undergoing routine maintenance work at the time. This paper presents an analysis of the SL-1 reactor excursion using the RELAP5-3D thermal-hydraulic and nuclear analysis code, with the intent of simulat… more
Date: November 8, 2007
Creator: Francisco, A.D. and Tomlinson, E. T.
Partner: UNT Libraries Government Documents Department
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A simple and realistic model of supersymmetry breaking

Description: We present a simple and realistic model of supersymmetry breaking. In addition to the minimal supersymmetric standard model, we only introduce a hidden sector gauge group SU(5) and three fields X, F and \bar{F}. Supersymmetry is broken at a local minimum of the potential, and its effects are transmitted to the supersymmetric standard model sector through both standard model gauge loops and local operators suppressed by the cutoff scale, which is taken to be the unification scale. The form of th… more
Date: September 25, 2007
Creator: Nomura, Yasunori & Papucci, Michele
Partner: UNT Libraries Government Documents Department
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Importance of the (n,gamma) Cm-247 Evaluation on Neutron Emission in Fast Reactor Fuel Cycle Analysis

Description: As part of the GNEP program, it is envisioned to build a fast reactor for the transmutation of minor actinides. The spent nuclear fuel from the current fleet of light water reactors would be recycled, the current baseline is the UREX+1a process, and would act as a feed for the fast reactor. As the fuel is irradiated in a fast reactor a certain quantity of minor actinides would thus build up in the fuel stream creating possible concerns with the neutron emission of these minor actinides for fuel… more
Date: November 1, 2007
Creator: Forget, Benoit; Asgari, Mehdi & Ferrer, Rodolfo M.
Partner: UNT Libraries Government Documents Department
open access

Complexation of U(VI) with 1-Hydroxyethane-1,1-diphosphonicAcid (HEDPA) in Acidic to Basic Solutions

Description: Complexation of U(VI) with 1-hydroxyethane-1,1-diphosphonic acid (HEDPA) in acidic to basic solutions has been studied with multiple techniques. A number of 1:1 (UO{sub 2}H{sub 3}L), 1:2 (UO{sub 2}H{sub j}L{sub 2} where j = 4, 3, 2, 1, 0 and -1) and 2:2 ((UO{sub 2}){sub 2}H{sub j}L{sub 2} where j = 1, 0 and -1) complexes form, but the 1:2 complexes are the major species in a wide pH range. Thermodynamic parameters (formation constants, enthalpy and entropy of complexation) were determined by po… more
Date: January 24, 2007
Creator: Reed, W. A.; Rao, L.; Zanonato, P.; Garnov, A.; Powell, B. A. & Nash, K. L.
Partner: UNT Libraries Government Documents Department
open access

1,2- Hydroxypyridonates as Contrast Agents for Magnetic ResonanceImaging: TREN-1,2-HOPO

Description: 1,2-Hydroxypyridinones (1,2-HOPO) form very stable lanthanide complexes that may be useful as contrast agents for Magnetic Resonance Imaging (MRI). X-ray diffraction of single crystals established that the solid state structures of the Eu(III) and the previously reported [Inorg. Chem. 2004, 43, 5452] Gd(III) complex are identical. The recently discovered sensitizing properties of 1,2-HOPO chelates for Eu(III) luminescence allow direct measurement of the number if water molecules in the metal co… more
Date: May 8, 2007
Creator: Jocher, Christoph J.; Moore, Evan G.; Xu, Jide; Avedano, Stefano; Botta, Mauro; Aime, Silvio et al.
Partner: UNT Libraries Government Documents Department
open access

Search for new physics in lepton + photon + X events with 929 pb**(-1) of p anti-p collisions at s**(1/2) = 1.96-TeV

Description: The authors present results of a search at CDF in 929 {+-} 56 pb{sup -1} of p{bar p} collisions at 1.96 TeV for the anomalous production of events containing a high-transverse momentum charged lepton ({ell}, either e or {mu}) and photon ({gamma}), accompanied by missing transverse energy (E{sub T}), and/or additional leptons and photons, and jets (X). They use the same selection criteria as in a previous CDF Run I search, but with an order-magnitude larger data set, a higher p{bar p} collisions… more
Date: February 1, 2007
Creator: Abulencia, A.; /Illinois U., Urbana; Adelman, J.; U., /Chicago; Affolder, T.; /UC, Santa Barbara et al.
Partner: UNT Libraries Government Documents Department
open access

Lattice QCD results for the B --> D(*) l nu form factors: F(1) and G(1)

Description: I review the current status of lattice QCD calculations of the B {yields} D and B {yields} D* form factors and discuss prospects for their improvement. Successful calculations within the quenched approximation demonstrate the power of lattice methods for calculating F(1) and G(1), and the unquenched calculations in progress should soon allow for a 2-3% exclusive determination of |Vcb|.
Date: January 1, 2007
Creator: Van de Water, R.S.
Partner: UNT Libraries Government Documents Department
open access

Commentary on Keith Augustine's Paper [#1]

Description: Abstract: Keith Augustine claims that near-death experiences are actually hallucinations. However, this proposition has several serious problems that I explicate in this commentary.
Date: Autumn 2007
Creator: Serdahely, William
Partner: UNT Libraries
open access

Prediction of the bubble point pressure for the binary mixture of ethanol and 1,1,1,2,3,3,3-heptafluoropropane from Gibbs ensemble Monte Carlo simulations using the TraPPE force field

Description: Configurational-bias Monte Carlo simulations in the Gibbs ensemble using the TraPPE force field were carried out to predict the pressure-composition diagrams for the binary mixture of ethanol and 1,1,1,2,3,3,3-heptafluoropropane at 283.17 and 343.13 K. A new approach is introduced that allows to scale predictions at one temperature based on the differences in Gibbs free energies of transfer between experiment and simulation obtained at another temperature. A detailed analysis of the molecular s… more
Date: February 28, 2007
Creator: Rai, N; Rafferty, J L; Maiti, A & Siepmann, I
Partner: UNT Libraries Government Documents Department
open access

Search for stopped gluinos from p-anti-p collisions at s**(1/2) = 1.96-TeV

Description: Long-lived, heavy particles are predicted in a number of models beyond the standard model of particle physics. We present the first direct search for such particles' decays, occurring up to 100 h after their production and not synchronized with an accelerator bunch crossing. We apply the analysis to the gluino ({tilde g}), predicted in split supersymmetry, which after hadronization can become charged and lose enough momentum through ionization to come to rest in dense particle detectors. Approx… more
Date: May 1, 2007
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Partner: UNT Libraries Government Documents Department
open access

Search for chargino-neutralino production in p anti-p collisions at s**(1/2) = 1.96-TeV

Description: We present the results of a search for associated production of the chargino and neutralino supersymmetric particles using up to 1.1 fb{sup -1} of integrated luminosity collected by the CDF II experiment at the Tevatron p{bar p} collider at a center-of-mass energy of 1.96 TeV. The search is conducted by analyzing events with a large transverse momentum imbalance and either three charged leptons or two charged leptons of the same electric charge. The numbers of observed events are found to be co… more
Date: July 1, 2007
Partner: UNT Libraries Government Documents Department
open access

Measurement of sigma(chi(c2)B(chi(c2) ---> J / psi gamma) / sigma(chi(c1)B(chi(c1) ---> J / psi gamma) in p anti-p collisions at s**(1/2) = 1.96-TeV

Description: The authors measure the ratio of cross section times branching fraction, {sigma}{sub {chi}c2}{beta}({chi}{sub c2} {yields} J/{psi}{gamma})/{sigma}{sub {chi}c1}{beta}({chi}{sub c1} {yields} J/{psi}{gamma}), in 1.1 fb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV. This measurement covers the kinematic range p{sub T} (J/{psi}) > 4.0 GeV/c, |{eta}(J/{psi})| < 1.0, and p{sub T}({gamma}) > 1.0 GeV/c. For events due to prompt processes, they find R{sub p} = 0.395 {+-} 0.016(stat.) {… more
Date: March 1, 2007
Creator: Abulencia, A.; Adelman, J.; Affolder, T.; Akimoto, T.; Albrow, M. G.; Ambrose, D. et al.
Partner: UNT Libraries Government Documents Department
open access

Search for resonant t anti-t production in p anti-p collisions at s**(1/2) = 1.96-TeV

Description: We report on a search for narrow-width particles decaying to a top and antitop quark pair. The data set used in the analysis corresponds to an integrated luminosity of 680 pb{sup -1} collected with the Collider Detector at Fermilab in Run II. We present 95% confidence level upper limits on the cross section times branching ratio. Assuming a specific top color-assisted technicolor production model, the leptophobic Z{prime} with width {Gamma}{sub Z{prime}} = 0.012M{sub Z{prime}}, we exclude the m… more
Date: September 1, 2007
Creator: Aaltonen, T.; Phys., /Helsinki Inst. of; Abulencia, A.; /Illinois U., Urbana; Adelman, J.; /Chicago U., EFI et al.
Partner: UNT Libraries Government Documents Department
open access

Measurement of the cross section for W-boson production in association with jets in ppbar collisions at s**(1/2) = 1.96-TeV

Description: We present a measurement of the cross section for W-boson production in association with jets in p{bar p} collisions at {radical}s = 1.96 TeV. The analysis uses a data sample corresponding to an integrated luminosity of 320 pb{sup -1} collected with the CDF II detector. W bosons are identified in their electron decay channel and jets are reconstructed using a cone algorithm. For each W + {ge} n-jet sample (n = 1-4) we measure {sigma}(p{bar p} {yields} W + {ge} n-jet) x {Beta}(W {yields} e{nu}) … more
Date: November 1, 2007
Creator: Aaltonen, T.
Partner: UNT Libraries Government Documents Department
open access

Search for anomalous production of multi-lepton events in p anti-p collisions at s**(1/2) = 1.96-TeV

Description: The authors report a search for the anomalous production of events with multiple charged leptons in p{bar p} collisions at {radical}s = 1.96 TeV using a data sample corresponding to an integrated luminosity of 346 pb{sup -1} collected by the CDF II detector at the Fermilab Tevatron. The search is divided into three-lepton and four-or-more-lepton data samples. They observe six events in the three-lepton sample and zero events in the {ge}4-lepton sample. Both numbers of events are consistent with… more
Date: January 1, 2007
Creator: Abulencia, A.; Adelman, Jahred A.; Affolder, T.; Akimoto, T.; Albrow, M.G.; Ambrose, D. et al.
Partner: UNT Libraries Government Documents Department
open access

Valence band anticrossing in GaBixAs1-x

Description: The optical properties of GaBixAs1-x (0.04< x< 0.08) grown by molecular beam epitaxy have been studied by photomodulated reflectance spectroscopy. The alloys exhibit a strong reduction in the bandgap as well as an increase in the spin-orbit splitting energy with increasing Bi concentration. These observations are explained by a valence band anticrossing model, which shows that a restructuring of the valence band occurs as the result of an anticrossing interaction between the extended stat… more
Date: July 11, 2007
Creator: Alberi, K.; Dubon, O. D.; Walukiewicz, W.; Yu, K. M.; Bertulis, K. & Krotkus, A.
Partner: UNT Libraries Government Documents Department
open access

Search for sneutrino particles in e + mu final states in p anti-p collisions at s**(1/2) = 1.96-TeV

Description: We report a search for R-parity violating production and decay of sneutrino particles in the e{mu} final state with 1.04 {+-} 0.06 fb{sup -1} of data collected with the D0 detector at the Fermilab Tevatron Collider in 2002-2006. Good agreement between the data and the standard model prediction is observed. With no evidence for new physics, we set limits on the R-parity violating couplings {lambda}'{sub 311} and {lambda}{sub 312} as a function of sneutrino mass.
Date: November 1, 2007
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
Partner: UNT Libraries Government Documents Department
open access

Search for new physics in high mass electron-positron events in p anti-p collisions at s**(1/2) = 1.96-TeV

Description: We report the results of a search for a narrow resonance in electron-positron events in the invariant mass range of 150-950 GeV/c{sup 2} using 1.3 fb{sup -1} of p{bar p} collision data at {radical}s=1.96 TeV collected by the CDF II detector at Fermilab. No significant evidence of such a resonance is observed and we interpret the results to exclude the standard model-like Z{prime} with a mass below 923 GeV/c{sup 2} and the Randall-Sundrum graviton with a mass below 807 GeV/c{sup 2} for k/{bar M}… more
Date: July 1, 2007
Creator: Aaltonen, T.; Abulencia, A.; Adelman, J.; Affolder, Anthony Allen; Akimoto, T.; Albrow, Michael G. et al.
Partner: UNT Libraries Government Documents Department
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