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Better devices are needed for the detection of aerosolized biological warfare agents. Advances in the ongoing development of one such device, the BioAerosol Mass Spectrometry (BAMS) system, are described here in detail. The system samples individual, micrometer-sized particles directly from the air and analyzes them in real-time without sample preparation or use of reagents. At the core of the BAMS system is a dual-polarity, single-particle mass spectrometer with a laser based desorption and ionization (DI) system. The mass spectra produced by early proof-of-concept instruments were highly variable and contained limited information to differentiate certain types of similar biological particles. The investigation of this variability and subsequent changes to the DI laser system are described. The modifications have reduced the observed variability and thereby increased the usable information content in the spectra. These improvements would have little value without software to analyze and identify the mass spectra. Important improvements have been made to the algorithms that initially processed and analyzed the data. Single particles can be identified with an impressive level of accuracy, but to obtain significant reductions in the overall false alarm rate of the BAMS instrument, alarm decisions must be made dynamically on the basis of multiple analyzed particles. …

Over the past decades the current theoretical description, the Standard Model of elementary particle physics, was solidified by many measurements as the basic theory describing fundamental particles and their interactions. It is extremely successful in explaining the high-precision data collected by experiments so far. The Standard Model includes several intrinsic parameters which have to be measured in experiments. Independent analyses of different physical processes can constrain those parameters. By combining those measurements physicists might be sensitive to physics beyond the Standard Model. If they are inconsistent it allows to get a hint on the theory that might supersede the Standard Model. The goal of the analysis presented in this thesis is to measure some of these parameters in the B{sub s} meson system. The B{sub s} meson, consisting of an anti-b and s quark, is not a pure mass eigenstate, thus allowing a B{sub s} meson to oscillate into its antiparticle via weak interacting processes. This is a general feature of any neutral meson. The history of meson mixing measurements is more then 50 years old. It was first observed in the kaon system. The oscillation in the B{sub d} system was measured very precisely by the B factories, whereas …

The primary mode of production of W{sup +} bosons in a p{bar p} collider is u + {bar d} {yields} W{sup +}. The u quark generally carries more momentum than the {bar d} and the resultant W{sup +} tends to be boosted in the proton direction. Similarly, W bosons are boosted in the anti-proton direction. This is observed as an asymmetry in the rapidity distributions of positive and negative W bosons. Measurement of this asymmetry serves as a probe of the momentum distribution of partons within the proton. These distributions are required as input to the calculation of every p{bar p} production cross section. This thesis presents the first measurement at D0 of the charge asymmetry of the W boson production cross section as measured in W {yields} ev decays in 0.3 fb{sup -1} of p{bar p} collisions collected with the D0 Detector. Theoretical predictions made using the CTEQ6.1M and MRST(2004) parton distribution functions are compared with the measurement.

Excitation functions for the 1n and 2n exit channels of the 208Pb(51V,xn)259-xDb reaction were measured. A maximum cross section of the 1n exit channel of 2070+1100/-760 pb was measured at an excitation energy of 16.0 +- 1.8 MeV. For the 2n exit channel, a maximum cross section of 1660+450/-370 pb was measured at 22.0 +- 1.8 MeV excitation energy. The 1n excitation function for the 209Bi(50Ti,n)258Db reaction was remeasured, resulting in a cross section of 5480+1730/1370 pb at an excitation energy of 16.0 +- 1.6 MeV. Differences in cross section maxima are discussed in terms of the fusion probability below the barrier. The extraction of niobium (Nb) and tantalum (Ta) from hydrochloric acid and mixed hydrochloric acid/lithium chloride media by bis(2-ethylhexyl) hydrogen phosphate (HDEHP) and bis(2-ethylhexyl) hydrogen phosphite (BEHP) was studied. The goal of the experiments was to find a system that demonstrates selectivity among the members of group five of the Periodic Table and is also suitable for the study of dubnium (Db, Z = 105). Experiments with niobium and tantalum were performed with carrier (10-6 M), carrier free (10-10 M) and trace (10-16 M) concentrations of metal using hydrochloric acid solution with concentrations ranging from 1 - 11 …

MiniBooNE seeks to corroborate or refute the unconfirmed oscillation result from the LSND experiment. If correct, the result implies that a new kind of massive neutrino, with no weak interactions, participates in neutrino oscillations. MiniBooNE searches for {nu}{sub {mu}} {yields} {nu}{sub e} oscillations with the Fermi National Accelerator Laboratory 8 GeV beam line, which produces a {nu}{sub {mu}} beam with an average energy of {approx} 0.8 GeV and an intrinsic {nu}{sub e} content of 0.4%. The neutrino detector is a 6.1 m radius sphere filled with CH{sub 2}, viewed by 1540 photo-multiplier tubes, and located 541 m downstream from the source. This work focuses on the estimation of systematic errors associated with the neutrino flux and neutrino interaction cross section predictions, and in particular, on constraining these uncertainties using in-situ MiniBooNE {nu}{sub {mu}} charged current quasielastic (CCQE) scattering data. A data set with {approx} 100,000 events is identified, with 91% CCQE purity. This data set is used to measure several parameters of the CCQE cross section: the axial mass, the Fermi momentum, the binding energy, and the functional dependence of the axial form factor on four-momentum transfer squared. Constraints on the {nu}{sub {mu}} and {nu}{sub e} fluxes are derived using …

Despite more than thirty years having elapsed since the discovery of CP violation, our understanding about the source and the nature of this phenomenon is still very limited. In the standard model of particle physics, CP violation is due to the presence of an non-irreducible weak phase in the Cabibbo-Kabayashi-Maskawa(CKM) matrix. Up to now, all the experimental results are in good agreement with the standard model. However, it is important for us to over-constrain the CKM quark-mixing matrix and explore the possibility of new physics beyond the standard model. The B meson provides an ideal place to measure CP violation due to its heavy mass and potentially large CP-violating effects. In particular, the angle {gamma} of the Unitary Triangle relating the elements of the CKM matrix is extremely crucial in terms of CP violation and constraints on the new physics models. Various methods using B{sup -} {yields} D{sup 0}K{sup -} decays have been proposed to measure based on the interference between the V{sub cb} and V{sub ub} amplitudes. Despite the simple concept, the measurement turns out to be experimentally challenging due to the small branching fraction and the small value of {tau}{sub B}, the amplitude ratio between the two contributing …

This dissertation discusses a data collection experiment within the Actinide Isomer Identification project (AID). The AID project is the investigation of an active interrogation technique that utilizes nuclear isomer production, with the goal of assisting in the interdiction of illicit nuclear materials. In an attempt to find and characterize isomers belonging to 235U and its fission fragments, a 232Th target was bombarded with a monoenergetic 6Li ion beam, operating at 45 MeV.

The new trigger processor, the Silicon Vertex Tracking (SVT), has dramatically improved the B physics capabilities of the upgraded CDF II Detector; for the first time in a hadron collider, the SVT has enabled the access to non-lepton-triggered B meson decays. Within the new available range of decay modes, the B{sub s}{sup 0} {yields} D{sub s}{sup -}{pi}{sup +} signature is of paramount importance in the measurement of the {Delta}m{sub s} mixing frequency. The analysis reported here is a step towards the measurement of this frequency; two where our goals: carrying out the absolute calibration of the opposite side flavor taggers, used in the {Delta}m{sub s} measurement; and measuring the B{sub d}{sup 0} mixing frequency in a B {yields} D{pi} sample, establishing the feasibility of the mixing measurement in this sample whose decay-length is strongly biased by the selective SVT trigger. We analyze a total integrated luminosity of 355 pb{sup -1} collected with the CDF II Detector. By triggering on muons, using the conventional di-muon trigger; or displaced tracks, using the SVT trigger, we gather a sample rich in bottom and charm mesons.

The fundamental motivation for the research presented in this dissertation was the need to development a more accurate prediction method for characterization of mixed radiation fields around medical electron accelerators (MEAs). Specifically, a model is developed for simulation of neutron and other particle production from photonuclear reactions and incorporated in the Monte Carlo N-Particle (MCNP) radiation transport code. This extension of the capability within the MCNP code provides for the more accurate assessment of the mixed radiation fields. The Nuclear Theory and Applications group of the Los Alamos National Laboratory has recently provided first-of-a-kind evaluated photonuclear data for a select group of isotopes. These data provide the reaction probabilities as functions of incident photon energy with angular and energy distribution information for all reaction products. The availability of these data is the cornerstone of the new methodology for state-of-the-art mutually coupled photon-neutron transport simulations. The dissertation includes details of the model development and implementation necessary to use the new photonuclear data within MCNP simulations. A new data format has been developed to include tabular photonuclear data. Data are processed from the Evaluated Nuclear Data Format (ENDF) to the new class ''u'' A Compact ENDF (ACE) format using a standalone processing …

Magnetic resonance is the most powerful analytical tool used by chemists today. Its applications range from determining structures of large biomolecules to imaging of human brains. Nevertheless, magnetic resonance remains a relatively young field, in which many techniques are currently being developed that have broad applications. In this dissertation, two new techniques are presented, one that enables the determination of torsion angles in solid-state peptides and proteins, and another that involves imaging of heterogenous materials at ultra-low magnetic fields. In addition, structural studies of the prion protein via solid-state NMR are described. More specifically, work is presented in which the dependence of chemical shifts on local molecular structure is used to predict chemical shift tensors in solid-state peptides with theoretical ab initio surfaces. These predictions are then used to determine the backbone dihedral angles in peptides. This method utilizes the theoretical chemicalshift tensors and experimentally determined chemical-shift anisotropies (CSAs) to predict the backbone and side chain torsion angles in alanine, leucine, and valine residues. Additionally, structural studies of prion protein fragments are described in which conformationally-dependent chemical-shift measurements were made to gain insight into the structural differences between the various conformational states of the prion protein. These studies are of …

This work presents measurements of two diffractive production ratio for heavy flavour physics with the use of a reconstructed J/{psi} {yields} {mu}{sup +}{mu}{sup -} sample in p{bar p} collisions at {radical}s = 1.96 TeV using the D0 detector at Fermilab Tevatron. These events were selected using the Luminosity Monitor detectors, the calorimeter system and the muon system in a pseudo-rapidity region with range 2.7 {le} |{eta}| {le} 4.4. The measured ratio were estimated to be N{sub diff}{sup J/{psi}}/N{sub total}{sup J/{psi}} = (1.74 {+-} 0.16(stat) {+-} 0.13(syst))% e N{sub diff}{sup b}/N{sub total}{sup b} = (0.79 {+-} 0.11(stat) {+-} 0.23(syst))%.

Measurements of the inclusive diffractive Z {yields} {mu}{sup +}{mu}{sup -} cross section with gap requirement for M{sub {mu}}{sub {mu}} > 40 GeV at {radical} s = 1.96 TeV and fraction of Z bosons produced diffractively with gap requirement from Z inclusive production are presented. The measurements are performed using a data sample corresponding to an integrated luminosity of 820 pb{sup -1}, collected with the D0 detector at the Tevatron, between 2002 to 2005. A total of 39945 di-muons events are selected and final results of: {sigma}{sub Diff}{sup gap} x Br(Z/{gamma}* {yields} {mu}{sup +}{mu}{sup -}) = 4.09 {+-} 0.64(stat.) {+-} 0.88(syst.) {+-} 0.27(lumi.) pb and, R{sub Diff}{sup gap} = 1.92 {+-} 0.30(stat.) {+-} 0.41(syst.) {+-} 0.12(lumi) % are obtained. In addition, d{sigma}/d{zeta} and d{sigma}/dy distributions are presented and they are compared with diffractive montecarlo (POMWIG). A reasonable agreement is obtained in this comparation. Finally, comparison of fraction of Z bosons produced diffractively with gap requirement (gap fraction) as measured with D0 during Run I of the Tevatron is compared. A good agreement is found for gap fraction results.

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It is well recognized that half the countries in the world will face significant fresh water shortages in the next 20 years, due largely to growing populations and increased agricultural and industrial demands (Gleick, 1997). These shortages will significantly limit economic growth, decrease the quality of life and human health for billions of people, and could potentially lead to violence and conflict over securing scarce supplies of water. In the Middle East, groundwater represents an important part of water supply in most locations, yet it is the least understood and one of the most fragile components of the entire water resource system. The occurrence of water underground contributes to the illusion of an infinite resource that is immune to anthropogenic activities. Nevertheless, as has been learned in the West, it can become highly impaired through the actions of man--through the disposal of human, animal, or industrial wastes, from excessive irrigation and fertilization practices in agriculture, or from simple overproduction and overexploitation--and can remain so for decades or even centuries. Finding solutions to groundwater resource and quality problems can be complex, time consuming, and costly. As is the case in many places in the world, but especially in the Middle East, …

The Forward Proton Detector (FPD) is a new sub-system of the D0 detector, a 5000 ton particle physics detector located at the Fermilab Tevatron proton-antiproton collider. The FPD was implemented for the Tevatron Run II and gives access to a wide range of diffractive scattering processes, where one or both of the beam particles remain intact. The analysis described in this thesis makes use of the dipole spectrometer of the FPD to tag outgoing antiprotons in events that have a dijet signature in the central D0 calorimeter. Properties of jets with a diffractive tag signature are compared to jets without such a signature yielding the first observation of tagged diffractive dijets at a 1.96 TeV center-of-mass energy.

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A variety of scenarios are considered which shed light upon the uses and limitations of classical geometric and topological notions in string theory. The primary focus is on situations in which D-brane or string probes of a given classical space-time see the geometry quite differently than one might naively expect. In particular, situations in which extra dimensions, non-commutative geometries as well as other non-local structures emerge are explored in detail. Further, a preliminary exploration of such issues in Lorentzian space-times with non-trivial causal structures within string theory is initiated.

The study of thermal decomposition in high explosive (HE) charges has been an ongoing process since the early 1900s. This work is specifically directed towards the analysis of PBX 9501. In the early 1970s, Dwight Jaeger of Los Alamos National Laboratory (LANL) developed a single-step, two-species kinetics system that was used in the development of one of the first finite element codes for thermal analyses known as EXPLO. Jaeger's research focused on unconfined spherical samples of HE charges to determine if varied heating ramps would cause detonation or deflagration. Tarver and McGuire of Lawrence Livermore National Laboratory (LLNL) followed soon after with a three-step, four-species kinetics system that was developed for confined spheres under relatively fast heating conditions. Peter Dickson et al. of LANL then introduced a kinetics system with four steps and five species that included bimolecular products to capture the effects of the endothermic phase change that the HE undergoes. The results of four experiments are examined to study the effectiveness of these kinetics systems. The experiments are: (1) The LLNL scaled thermal explosion (STEX) experiments on confined cylindrical charges with long heating ramps in the range of 90 hours. (2) The LLNL one-dimensional time to explosion (ODTX) …

This thesis reports the measurement of the inclusive charged particle (h{sup +} + h{sup -}) p{perpendicular} spectra for 1.7 < p{perpendicular} < 6 GeV/c at midrapidity (|{eta}| < 0.5) as a function of various centrality classes in Au+Au collisions at {radical}s{sub NN} = 130 GeV. Hadron suppression is observed relative to both scaled NN and peripheral Au+Au reference data, possibly indicating non-Abelian radiative energy loss in a hot, dense medium.

The WARP code is a robust electrostatic particle-in-cell simulation package used to model charged particle beams with strong space-charge forces. A fundamental operation associated with seeding detailed simulations of a beam transport channel is to generate initial conditions where the beam distribution is matched to the structure of a periodic focusing lattice. This is done by solving for periodic, matched solutions to a coupled set of ODEs called the Kapchinskij-Vladimirskij (KV) envelope equations, which describe the evolution of low-order beam moments subject to applied lattice focusing, space-charge defocusing, and thermal defocusing forces. Recently, an iterative numerical method was developed (Lund, Chilton, and Lee, Efficient computation of matched solutions to the KV envelope equations for periodic focusing lattices, Physical Review Special Topics-Accelerators and Beams 9, 064201 2006) to generate matching conditions in a highly flexible, convergent, and fail-safe manner. This method is extended and implemented in the WARP code as a Python package to vastly ease the setup of detailed simulations. In particular, the Python package accommodates any linear applied lattice focusing functions without skew coupling, and a more general set of beam parameter specifications than its predecessor. Lattice strength iteration tools were added to facilitate the implementation of problems with …

Slant-path buildup factors for photons between 1 keV and 10 MeV for nine radiation shielding materials (air, aluminum, concrete, iron, lead, leaded glass, polyethylene, stainless steel, and water) are calculated with the most recent cross-section data available using Monte Carlo and discrete ordinates methods. Discrete ordinates calculations use a 244-group energy structure that is based on previous research at Los Alamos National Laboratory (LANL), but extended with the results of this thesis, and its focused studies on low-energy photon transport and the effects of group widths in multigroup calculations. Buildup factor calculations in discrete ordinates benefit from coupled photon/electron cross sections to account for secondary photon effects. Also, ambient dose equivalent (herein referred to as dose) buildup factors were analyzed at lower energies where corresponding response functions do not exist in literature. The results of these studies are directly applicable to radiation safety at LANL, where the dose modeling tool Pandemonium is used to estimate worker dose in plutonium handling facilities. Buildup factors determined in this thesis will be used to enhance the code's modeling capabilities, but should be of interest to the radiation shielding community.

The ICF Program has undergone a significant change in 1999 with the decommissioning of the Nova laser and the transfer of much of the experimental program to the OMEGA laser at the University of Rochester. The Nova laser ended operations with the final experiment conducted on May 27, 1999. This marked the end to one of DOE's most successful experimental facilities. Since its commissioning in 1985, Nova performed 13,424 experiments supporting ICF, Defense Sciences, high-power laser research, and basic science research. At the time of its commissioning, Nova was the world's most powerful laser. Its early experiments demonstrated that 3{omega} light could produce high-drive, low-preheat environment required for indirect-drive ICE. In the early 1990s, the technical program on Nova for indirect drive ignition was defined by the Nova technical contract established by National Academy Review of ICF in 1990. Successful completion of this research program contributed significantly to the recommendation by the ICF Advisory Committee in 1995 to proceed with the construction of the National Ignition Facility? Nova experiments also demonstrated the utility of high-powered lasers for studying the physics of interest to Defense Sciences. Now, high-powered lasers along with pulsed-power machines are the principal facilities for studying high energy …

The authors report an investigation of the semileptonic decay {Xi}{sup 0} {yields} {sigma}{sup +} {mu}{sup -}{bar {nu}}{sub {mu}}. This decay was observed for the first time with nine identified events using the KTeV beam line and detector at Fermilab. The decay is normalized to the {Xi}{sup 0} beta decay mode and yields a value for the ratio of decay rates {Lambda}({Xi}{sup 0} {yields} {Sigma}{sup +} {mu}{sup -}{bar {nu}}{sub {mu}})/{Lambda}({Xi}{sup 0} {yields} {Sigma}{sup +}e{sup -}{bar {nu}}{sub e}) of (1.8{sub -0.5}{sup +0.7}(stat.) {+-} 0.2(syst.)) x 10{sup -2} at the 68.27% confidence level, being the official measurement of KTeV Collaboration. They also used the dominant decay {Xi}{sup 0} {yields} {Lambda}{pi}{sup 0}({Lambda} {yields} p{pi}{sup -}) as normalization mode in an independent analysis which corroborated with the main result. In addition, a new measurement of the {Xi}{sup 0} {yields} {Sigma}{sup +} e{sup -}{bar {nu}}{sub e} branching ratio is presented, based on 1139 events and normalized to the {Xi}{sup 0} {yields} {Lambda}{pi}{sup 0}({Lambda} {yields} p{pi}{sup -}) decay mode. The results are in agreement with the SU(3) flavor symmetric quark model.