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Semileptonic Decays and Sides of the Unitarity Triangle

Description: The elements of the CKM matrix enter the expressions for the decay rates and mixing amplitudes of hadrons. In some cases, the theoretical expressions are free of strong interaction effects, for example the CP asymmetry in B {yields} J/{psi} K{sub S}{sup 0}, so that measuring the CP asymmetry directly gives the value of sin 2{beta}, with the error in the result given by the experimental error in the measurement. In most cases, however, the experimentally measured quantities depend on strong inte… more
Date: May 1, 2003
Creator: Ligeti, Zoltan; Bauer, C.; Bernard, C.; Bigi, I.; Datta, M.; del Re, D. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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FFAG LATTICE FOR MUON ACCELERATION WITH DISTRIBUTED RF.

Description: A future muon collider or neutrino factory requires fast acceleration to minimize muon decay. We have previously described an FFAG ring that accelerated muons from 10 to 20 GeV in energy. The ring achieved its large momentum acceptance using a low-emittance lattice with a small dispersion. In this paper, we present an update on that ring. We have used design tools that more accurately represent the ring's behavior at large momentum offsets. We have also improved the dynamic aperture from the ea… more
Date: May 12, 2003
Creator: COURANT,E. D..TRBOJEVIC,D. BERG,S. J. BLASKIEWICZ,M. COURANT,E. D..TRBOJEVIC,D. BERG,S. J. BLASKIEWICZ,M. M. PALMER,R. GARREN,A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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The Impact of Humidity, Temperature and Ultraviolet Light on the Near-Field Environmental Fate of Pinacolyl Alcohol, Methyl Iodide, Methylphosphonic Dichloride (DCMP) and Thionyl Chloride Using an Environmental Wind Tunnel

Description: Understanding the near-field fate of parent chemicals and their decay products in the atmosphere provides essential information for the development of remote chemical sensors. To elucidate the near-field fate of candidate chemical signatures, selected gas phase compounds were introduced into atmospheres of varying humidity, temperature and incident light flux. These atmospheres were maintained in an environmental wind tunnel for periods typical of near-field transport scenarios. The range of hu… more
Date: January 24, 2003
Creator: Driver, Crystal J.; Johnson, Timothy J.; Su, Yin-Fong; Alexander, M. Lizabeth; Fellows, Robert J.; Magnuson, Jon K. et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Radiative Corrections to One-Photon Decays of Hydrogenic Ions

Description: Radiative corrections to the decay rate of n = 2 states of hydrogenic ions are calculated. The transitions considered are the M1 decay of the 2s state to the ground state and the E1(M2) decays of the 2p{sub 1/2} and 2p{sub 3/2} states to the ground state. The radiative corrections start in order {alpha}(Z{alpha}){sup 2}, but the method used sums all orders of Z{alpha}. The leading {alpha}(Z{alpha}){sup 2} correction for the E1 decays is calculated and compared with the exact result. The extensi… more
Date: November 11, 2003
Creator: Sapirstein, J; Pachucki, K & Cheng, K T
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Comparison of Three Afterglow Morphologies

Description: Herein we compare three functional families for afterglow morphologies: the homogeneous afterglow with constant shock surface energy density, the structured afterglow for which the energy density decays as a power-law as a function of viewer angle, and the gaussian afterglow which has an exponential decay of energy density with viewer angle. We simulate observed lightcurves and polarization curves for each as seen from a variety of observer vantage points. We find that the homogeneous jet is li… more
Date: December 23, 2003
Creator: Salmonson, J D; Rossi, E & Lazzati, D
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Rates, Polarizations, and Asymmetries in Charmless Vector-Vector B Decays

Description: With a sample of approximately 89 million B{bar B} pairs collected with the BABAR detector, they measure branching fractions, determine the degree of longitudinal polarization, and search for direct CP violation in the decays B{sup 0} {yields} {phi}K*{sup 0} and B{sup +} {yields} {phi}K*{sup +}. They perform a search for other charmless vector-vector B decays involving {rho} and K*(892) resonances and observe the decays B{sup +} {yields} {rho}{sup 0} K*{sup +} and B{sup +} {yields} {rho}{sup 0}… more
Date: March 11, 2003
Creator: Aubert, B.; Barate, R.; Boutigny, D.; Gaillard, J.-M.; Hicheur, A.; Karyotakis, Y. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Results from the First {sup 249}Cf + {sup 48}Ca Experiment

Description: The present paper reports the results of an attempt aimed at the synthesis of element 118 in the reaction {sup 249}Cf({sup 48}Ca,3n){sup 294}118. The experiment was performed employing the Dubna Gas-filled Recoil Separator and the U400 heavy-ion cyclotron at FLNR, JINR, Dubna. In the course of a 2300-hour irradiation of an enriched {sup 249}Cf target (0.23 mg/cm{sup 2}) with a beam of 245-MeV {sup 48}Ca ions, we accumulated a total beam dose of 2.5 x 10{sup 19} ions. We detected two events that… more
Date: February 3, 2003
Creator: Oganessian, Y T; Utyonkov, V K; Lobanov, Y V; Abdullin, F S; Polyakov, A N; Shirokovsky, I V et al.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Silicon Surface and Heterojunction Interface Passivation Studies by Lifetime Measurements: Preprint

Description: We report two investigations conducted by using photoconductivity decay lifetime measurement. The first is crystalline silicon (c-Si) surface passivation using quinhydrone/methanol (QM) for bulk minority-carrier lifetime measurement. QM shows great promise as a substitute for iodine-based solutions because of its superior stability and minimized surface-recombination velocity in silicon. The second is interface passivation in an amorphous silicon (a-Si)/c-Si heterojunction structure as a parall… more
Date: August 1, 2003
Creator: Page, M. R.; Wang, Q.; Wang, T. H.; Johnston, S. W. & Ciszek, T. F.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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General Constraints on Cross Sections Deduced from Surrogate Reactions

Description: Cross sections that cannot be measured in the laboratory, e.g. because the target lifetime is too short, can be inferred indirectly from a different reaction forming the same compound system, but with a more accessible beam/target combination (the ''surrogate-reaction'' technique). The reactions share the same compound system and a common decay mechanism, but they involve different formation processes. Therefore, an implicit constraint is imposed on the inferred cross section deduced from the m… more
Date: August 14, 2003
Creator: Younes, W.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Neutrinoless Double Beta Decay in Light of SNO Salt Data

Description: In the SNO data from its salt run, probably the most significant result is the consistency with the previous results without assuming the 8B energy spectrum. In addition, they have excluded the maximal mixing at a very high confidence level. This has an important implication on the double beta decay experiments. For the inverted or degenerate mass spectrum, we find bar<m_nu>_ee bar> 0.013 eV at 95percent CL, and the next generation experiments can discriminate Majorana and Dirac neutri… more
Date: September 11, 2003
Creator: Murayama, Hitoshi & Pena-Garay, Carlos
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Time-reversal violation in beta decay

Description: At present there is no unambigous direct evidence for time-reversal (T) violation in the fundamental interactions. But T-violation is intimately connected with CP-violation by the CPT theorem. A stringent bound on possible violation of CPT invariance comes from the properties of K{sup 0} - {bar K}{sup 0} mixing [I]. In the following we shall assume that CPT violating interactions, if present, can be neglected, and use the terms 'T-violation' and 'CP-violation' interchangably.
Date: January 1, 2003
Creator: Herczeg, P. (Peter)
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Survey and alignment of the Fermilab MiniBooNE horn and target

Description: The first phase of the BooNE (Booster Neutrino Experiment) program at Fermilab is called MiniBooNE. One of the primary goals is to test for neutrino mass via a search for neutrino oscillations. The MiniBooNE consists of a Neutrino Beam and a 40-foot (12.2-meter) diameter Detector. The detector is located 500 m from the neutrino beam line fed by the 8 GeV protons Booster. The Neutrino Beam consists of four sections: the Target, the Horn (focusing system), the decay region, and the beam absorber.… more
Date: July 1, 2003
Creator: Oshinowo, Babatunde O'Sheg
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Chemical investigations of Element 108, Hassium (Hs)

Description: The basic aim of chemistry experiments of transactinide elements (TAN) is to establish their place in the periodic table of the elements, i.e. to determine if their chemical behavior is similar to the one of supposed homologs. In this contribution I will try to give an overview of all chemical experiments on element 108, hassium (Hs) that have been reported to date. Based on the systematics of the periodic table, Hs is expected to be a member of group 8 and therefore homologous to osmium (Os) a… more
Date: July 3, 2003
Creator: Dullmann, Christoph E.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Measurement of the Lambda 0(b) -> Lambda +(c) pi- branching ratio

Description: The authors present a measurement of the {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{sup +} {pi}{sup -} branching ratio in p{bar p} collisions at {radical}s = 1.96 TeV using 65 pb{sup -1} data collected by the Collider Detector at Fermilab (CDF). The measurement starts from reconstructing two decay modes: {Lambda}{sub b}{sup 0} {yields} {Lambda}{sub c}{sup +}{pi}{sup -}, where {Lambda}{sub c}{sup +} {yields} p K{sup -} {pi}{sup +}; and {bar B}{sup 0} {yields} D{sup +}{pi}{sup -}, where D{su… more
Date: January 1, 2003
Creator: Le, Yi
Item Type: Refine your search to only Thesis or Dissertation
Partner: UNT Libraries Government Documents Department
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Photochemical oxidation of oxalate in Pu-238 process streams

Description: For over forty years, NASA has relied on plutonium-238 in Radioisotope Thermoelectric Generator (RTG) units and Radioisotope Heater Units ( W s ) to provide power and heat for many space missions including Transit, Pioneer, Viking, Voyager, Galileo, Ulysses and Cassini. RHUs provide heat to keep key components warm in extremely cold environments found on planets, moons, or in deep space. RTGs convert heat generated from the radioactive decay of plutonium-238 into electricity using a themocouple… more
Date: January 1, 2003
Creator: Long, Kristy M.; Ford, Doris K. & Trujillo, Leonardo A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Coupling of Realistic Rate Estimates with Genomics for Assessing Contaminant Attenuation and Long-Term Plume Containment

Description: Natural attenuation of TCE under aerobic conditions at the INEEL Test Area North site was demonstrated largely on the basis of preferential loss of TCE relative to conservative solutes (PCE and H-3) along groundwater flow paths. First order degradation half-lives were calculated from the rate of preferential TCE loss. We are utilizing the same approach at other DOE sites that have aerobic TCE plumes to determine if aerobic natural attenuation of TCE is rapid enough at these sites to be environm… more
Date: June 1, 2003
Creator: Sorenson, Kent S. Jr.
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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Prediction of water seepage into a geologic repository for high-level radioactive waste

Description: Predicting the amount of water that may seep into waste emplacement drifts is important for assessing the performance of the proposed geologic repository for high-level radioactive waste at Yucca Mountain, Nevada. The repository would be located in thick, partially saturated fractured tuff that will be heated to above-boiling temperatures as a result of heat generation from the decay of nuclear waste. Since infiltrating water will be subject to vigorous boiling for a significant time period, th… more
Date: July 7, 2003
Creator: Birkholzer, Jens; Mukhophadhyay, Sumit & Tsang, Yvonne
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Modeling seepage into heated waste emplacement tunnels in unsaturated fractured rock

Description: Predicting the amount of water that may seep into waste emplacement tunnels (drifts) is important for assessing the performance of the proposed geologic repository for high-level radioactive waste at Yucca Mountain, Nevada. The repository will be located in thick, partially saturated fractured tuff that-for the first several hundred years after emplacement-will be heated to above-boiling temperatures as a result of heat generation from the decay of radioactive waste. Heating of rock water to ab… more
Date: October 1, 2003
Creator: Birkholzer, Jens T.; Mukhopihadhyay, Sumit & Tsang, Yvonne W.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Recoil ion charge state distribution following the beta(sup +) decay of {sup 21}Na

Description: The charge state distribution following the positron decay of 21Na has been measured, with a larger than expected fraction of the daughter 21Ne in positive charge states. No dependence on either the positron or recoil nucleus energy is observed. The data is compared to a simple model based on the sudden approximation. Calculations suggest a small but important contribution from recoil ionization has important consequences for precision beta decay correlation experiments detecting recoil ions.
Date: January 3, 2003
Creator: Scielzo, Nicholas D.; Freedman, Stuart J.; Fujikawa, Brian K. & Vetter, Paul A.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Studies of the N=90 region: The decay of 154Eu to 154Gd

Description: The decay of {sup 154}Eu {yields} {sup 154}Gd has been studied by {gamma}-ray singles and {gamma}-{gamma} coincidence spectroscopy using an array of 20 Compton-suppressed Ge detectors. The primary goal of the work was to confirm or refute a large number of questionable features in the decay scheme: the outcome is the removal of 8 levels from the previously adopted scheme, with the result that a new type of collective band is revealed. Many weak decay branches for the decay are clarified. These … more
Date: December 5, 2003
Creator: Kulp, W. D.; Wood, J. L.; Krane, K. S.; Loats, J.; Schmelzenbach, P.; Stapels, C. J. et al.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Radiation Effects in Nuclear Waste Materials

Description: The objective of this project is to develop a fundamental understanding of radiation effects in glasses and ceramics, as well as the influence of solid-state radiation effects on aqueous dissolution kinetics, which may impact the performance of nuclear waste forms and stabilized nuclear materials. This work provides the underpinning science to develop improved glass and ceramic waste forms for the immobilization and disposition of high-level tank waste, excess plutonium, plutonium residues and … more
Date: June 1, 2003
Creator: Weber, William J.; Wang, Lumin; Hess, Nancy J.; Icenhower, Jonathan P. & Thevuthasan, Suntharampillai (Theva)
Item Type: Refine your search to only Report
Partner: UNT Libraries Government Documents Department
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WMAPping out Neutrino Masses

Description: Recent data from the Wilkinson Microwave Anisotropy Probe (WMAP) place important bounds on the neutrino sector. The precise determination of the baryon number in the universe puts a strong constraint on the number of relativistic species during Big-Bang Nucleosynthesis. WMAP data, when combined with the 2dF Galaxy Redshift Survey (2dFGRS), also directly constrain the absolute mass scale of neutrinos. These results impinge upon a neutrino oscillation interpretation of the result from the Liquid … more
Date: October 28, 2003
Creator: Pierce, Aaron & Murayama, Hitoshi
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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Quantum interferometry in rho{sup 0} production in ultra-peripheral heavy ion collisions

Description: In {rho}{sup 0} photoproduction in ultra-peripheral heavy ion collisions, either ion can be the photon emitter or the target. The two possibilities are indistinguishable, and they should be able to interfere, reducing {rho}{sup 0} production at low transverse momentum, p{sub T} < {h_bar}/<b>, where <b> is the median impact parameter. The two {rho}{sup 0} production points are separated by <b> {approx} 18-46 fm, while the {rho}{sup 0} decay before travelling 1 fm. The two de… more
Date: December 30, 2003
Creator: Klein, Spencer R.
Item Type: Refine your search to only Article
Partner: UNT Libraries Government Documents Department
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