This project will develop an analytical tool to calculate performance of HMX based PBXs in the skid test. The skid-test is used as a means to measure sensitivity for large charges in handling situations. Each series of skid tests requires dozens of drops of large billets. It is proposed that the reaction (or lack of one) of PBXs in the skid test is governed by the mechanical properties of the binder. If true, one might be able to develop an analytical tool to estimate skid test behavior for new PBX formulations. Others over the past 50 years have tried to develop similar models. This project will research and summarize the works of others and couple the work of 3 into an analytical tool that can be run on a PC to calculate drop height of HMX based PBXs. Detonation due to dropping a billet is argued to be a dynamic thermal event. To avoid detonation, the heat created due to friction at impact, must be conducted into the charge or the target faster than the chemical kinetics can create additional energy. The methodology will involve numerically solving the Frank-Kamenetskii equation in one dimension. The analytical problem needs to be bounded in terms of how much heat is introduced to the billet and for how long. Assuming an inelastic collision with no rebound, the billet will be in contact with the target for a short duration determined by the equations of motion. For the purposes of the calculations, it will be assumed that if a detonation is to occur, it will transpire within that time. The surface temperature will be raised according to the friction created using the equations of motion of dropping the billet on a rigid surface. The study will connect the works of Charles Anderson, Alan Randolph, Larry …
The Main Injector Neutrino Oscillation Search (MINOS) is a long baseline neutrino oscillation experiment. The MINOS Far Detector, located in the Soudan Underground Laboratory in Soudan MN, has been collecting data since August 2003. The scope of this dissertation involves identifying the atmospheric neutrino induced muons that are created by the neutrinos interacting with the rock surrounding the detector cavern, performing a neutrino oscillation search by measuring the oscillation parameter values of {Delta}m{sub 23}{sup 2} and sin{sup 2} 2{theta}{sub 23}, and searching for CPT violation by measuring the charge ratio for the atmospheric neutrino induced muons. A series of selection cuts are applied to the data set in order to extract the neutrino induced muons. As a result, a total of 148 candidate events are selected. The oscillation search is performed by measuring the low to high muon momentum ratio in the data sample and comparing it to the same ratio in the Monte Carlo simulation in the absence of neutrino oscillation. The measured double ratios for the ''all events'' (A) and high resolution (HR) samples are R{sub A} = R{sub low/high}{sup data}/R{sub low/high}{sup MC} = 0.60{sub -0.10}{sup +0.11}(stat) {+-} 0.08(syst) and R{sub HR} = R{sub low/high}{sup data}/R{sub low/high}{sup MC} = 0.58{sub -0.11}{sup +0.14}(stat) {+-} 0.05(syst), respectively. Both event samples show a significant deviation from unity giving a strong indication of neutrino oscillation. A combined momentum and zenith angle oscillation fit is performed using the method of maximum log-likelihood with a grid search in the parameter space of {Delta}m{sup 2} and sin{sup 2} 2{theta}. The best fit point for both event samples occurs at {Delta}m{sub 23}{sup 2} = 1.3 x 10{sup -3} eV{sup 2}, and sin{sup 2} 2{theta}{sub 23} = 1. This result is compatible with previous measurements from the Super Kamiokande experiment and Soudan 2 experiments. The MINOS Far …
This document describes the measurements of the branching fractions and isospin violations of the radiative electroweak penguin decays B {yields} ({rho}/{omega}){gamma} at the asymmetric-energy e{sup +}e{sup -} PEP-II collider with the BABAR detector. Together with the previously measured branching fractions of the decays B {yields} K*{gamma} the ratio of CKM-matrix elements |V{sub td}/V{sub ts}| are extracted and the length of the far side of the unitarity triangle is determined.
The MINOS Far Detector is a 5400 ton iron calorimeter located at the Soudan state park in Soudan Minnesota. The MINOS far detector can observe atmospheric neutrinos and separate charge current {nu}{sub {mu}} and {bar {nu}}{sub {mu}} interactions by using a 1.4 T magnetic field to identify the charge of the produced muon. The CPT theorem requires that neutrinos and anti-neutrinos oscillate in the same way. In a fiducial exposure of 5.0 kilo-ton years a total of 41 candidate neutrino events are observed with an expectation of 53.1 {+-} 7.6(system.) {+-} 7.2(stat.) unoscillated events or 31.6 {+-} 4.7(system.) {+-} 5.6(stat.) events with {Delta}m{sup 2} = 2.4 x 10{sup -3} eV{sup 2}, sin{sup 2}(2{theta}) = 1.0 as oscillation parameters. These include 28 events which can have there charge identified with high confidence. These 28 events consist of 18 events consistent with being produced by {nu}{sub {mu}} and 10 events being consistent with being produced by {bar {nu}}{sub {mu}}. No evidence of CPT violation is observed.
Since the invention of quantum mechanics, even the simplest example of collisional breakup in a system of charged particles, e{sup {minus}} + H {r_arrow} H{sup +} + e{sup {minus}} + e{sup {minus}}, has stood as one of the last unsolved fundamental problems in atomic physics. A complete solution requires calculating the energies and directions for a final state in which three charged particles are moving apart. Advances in the formal description of three-body breakup have yet to lead to a viable computational method. Traditional approaches, based on two-body formalisms, have been unable to produce differential cross sections for the three-body final state. Now, by using a mathematical transformation of the Schrodinger equation that makes the final state tractable, a complete solution has finally been achieved, Under this transformation, the scattering wave function can be calculated without imposing explicit scattering boundary conditions. This approach has produced the first triple differential cross sections that agree on an absolute scale with experiment as well as the first ab initio calculations of the single differential cross section.
Experimental, numerical, and analytical work has shown that the response of a shell to a distributed force wave possesses unique characteristics which are dependent on the nature of structure attached to the shell. Specific characteristics which influence the response are the distribution of the discontinuities around the circumference (periodic/aperiodic), the impedance of the discontinuities relative to that of the shell, and the type of impedance (mass or stiffness). Traditional shell theory predicts low frequency, radial-dominated structural mode shapes of a shell with a sinusoidal distribution of displacement amplitudes. Due to the orthogonal nature of these mode shapes, the response of the structure to a traveling radial force wave with sinusoidal content at a given harmonic is due solely to the response of the mode shape with harmonic content of the same order. Introduction of impedance discontinuities to a shell yield complex mode shapes, which may be characterized by the summation of several harmonic components. These modes are no longer orthogonal in the presence of discontinuities, yielding harmonic content across various modal orders. As a result, a purely sinusoidal forcing function can excite several modes of the structure. Structural scattering as discussed in this paper refers to the phenomena in which a force wave at a given harmonic scatters into the response of modes with different harmonics. An experimental investigation into the harmonic scattering behavior of a shell due to mass discontinuities is presented in this paper. Knowledge of the key structural characteristics which influence scattering and their behavior will allow for a diagnostic tool when assessing the structural response of more complex cylindrical structures. Experimentally obtained data presented in this paper demonstrates some expected scattering characteristics of a cylindrical shell in the presence of periodically and aperiodically distributed masses. Some unique characteristics of the response of a shell in the …
In this thesis, results of neutrino-nucleon neutral current (NC) elastic scattering analysis are presented. Neutrinos interact with other particles only with weak force. Measurement of cross-section for neutrino-nucleon reactions at various neutrino energy are important for the study of nucleon structure. It also provides data to be used for beam flux monitor in neutrino oscillation experiments. The cross-section for neutrino-nucleon NC elastic scattering contains the axial vector form factor G{sub A}(Q{sup 2}) as well as electromagnetic form factors unlike electromagnetic interaction. G{sub A} is propotional to strange part of nucleon spin ({Delta}s) in Q{sup 2} {yields} 0 limit. Measurement of NC elastic cross-section with smaller Q{sup 2} enables us to access {Delta}s. NC elastic cross-sections of neutrino-nucleon and antineutrino-nucleon were measured earlier by E734 experiment at Brookheaven National Laboratory (BNL) in 1987. In this experiment, cross-sections were measured in Q{sup 2} > 0.4 GeV{sup 2} region. Result from this experiment was the only published data for NC elastic scattering cross-section published before our experiment. SciBooNE is an experiment for the measurement of neutrino-nucleon scattering cross-secitons using Booster Neutrino Beam (BNB) at FNAL. BNB has energy peak at 0.7 GeV. In this energy region, NC elastic scattering, charged current elastic scattering, charged current pion production, and neutral current pion production are the major reaction branches. SciBar, electromagnetic calorimeter, and Muon Range Detector are the detectors for SciBooNE. The SciBar consists of finely segmented scintillators and 14336 channels of PMTs. It has a capability to reconstruct particle track longer than 8 cm and separate proton from muons and pions using energy deposit information. Signal of NC elastic scattering is a single proton track. In {nu}p {yields} {nu}p process, the recoil proton is detected. On the other hand, most of {nu}n {yields} {nu}n is invisible because there are only neutral particles in final …
This dissertation presents a preliminary measurement of the B{sup {+-}} lifetime through the full reconstruction of its decay chain, and the identification of top quark production in the electron plus jets channel using the displaced vertex b-tagging method. Its main contribution is the development, implementation and optimization of the Kalman filter algorithm for vertex reconstruction, and of the displaced vertex technique for tagging jets arising from b quark fragmentation, both of which have now become part of the standard D0 reconstruction package. These two algorithms fully exploit the new state-of-the-art tracking detectors, recently installed as part of the Run 2 D0 upgrade project. The analysis is based on data collected during Run 2a at the Fermilab Tevatron p{bar p} Hadron Collider up to April 2003, corresponding to an integrated luminosity of 60 pb{sup -1}. The measured B meson lifetime of {tau} = 1.57 {+-} 0.18 ps is in agreement with the current world average, with a competitive level of precision expected when the full data sample becomes available.
A method is presented to simultaneously separate the contributions to a sample of B{sub (s)}{sup 0} {yields} h{sup +}h{sup {prime}-} decays, where h = {pi} or K, and measure the B meson lifetimes in the sample while correcting for the bias in the lifetime distributions due to the hadronic trigger at the CDF experiment. Using 1 fb{sup -1} of data collected at CDF the B{sup 0} lifetime is measured as {tau}{sub B{sup 0}} = 1.558{sub -0.047}{sup +0.050}{sub stat} {+-} 0.028{sub syst} ps, in agreement with the world average measurement. The B{sub s}{sup 0} lifetime in the B{sub s}{sup 0} {yields} K{sup +}K{sup -} decay is measured as {tau}{sub B{sub s}{sup 0} {yields} K{sup +}K{sup -}} = 1.51{sub -0.11}{sup +0.13}{sub stat} {+-} 0.04{sub syst} ps. No difference is observed between the lifetime and other measurements of the average B{sub s}{sup 0} lifetime or the lifetime of the light B{sub s}{sup 0} mass eigenstate determined from B{sub s}{sup 0} {yields} J/{psi}{phi} decays. With the assumptions that B{sub s}{sup 0} {yields} K{sup +}K{sup -} is 100% CP-even and that {tau}{sub B{sub s}{sup 0}} = {tau}{sub B{sup 0}} the width difference in the B{sub s}{sup 0} system is determined as {Delta}{Lambda}{sup CP}/{Lambda} = 0.03{sub -0.15}{sup +0.17}{sub stat} {+-} 0.05{sub syst} using the current world average B{sup 0} lifetime. This is consistent with zero and with the current world average measurement.
This thesis describes a measurement of the branching fraction Br(B{sup 0}{sub s} {yields} D{sup (*)}{sub s} D{sup (*)}{sub s}) made using a data sample collected from proton-antiproton collisions at a centre-of-mass energy of 1.96 TeV, corresponding to approximately 1.3 fb{sup -1} of integrated luminosity collected in 2002--2006 by the D0 detector at the Fermilab Tevatron Collider. One D{sup (*)}{sub s} meson was partially reconstructed in the decay D{sub s} {yields} {phi}{mu}{nu}, and the other D{sup (*)}{sub s} meson was identified using the decay D{sub s} {yields} {phi}{pi} where no attempt was made to distinguish D{sub s} and D{sup *}{sub s} states. The resulting measurement is Br(B{sup 0}{sub s} {yields} D{sup (*)}{sub s} D{sup (*)}{sub s}) = 0.039{sup +0.019}{sub -0.017}(stat){sup +0.016}{sub -0.015}(syst). This was subsequently used to estimate the width difference {Delta}{Gamma}{sup CP}{sub s} in the B{sup 0}{sub s}-{anti B}{sup 0}{sub s} system: {Delta}{Gamma}{sup CP}{sub s}/{Gamma}{sub s} = 0.079{sup +0.038}{sub -0.035}(stat){sup +0.031}{sub 0.030}(syst), and is currently one of the most precise estimates of this quantity and consistent with the Standard Model.
A measurement of the inclusive Z/{gamma}* {yields} {mu}{sup +}{mu}{sup -} cross section for M{sub {mu}{mu}} > 40 GeV at {radical}s = 1.96 TeV is presented. The measurement is performed using a data sample corresponding to an integrated luminosity of 147.7 pb{sup -1}, collected with the D0 detector at the Tevatron, Fermilab, between September 2002 and October 2003. A total of 14352 di-muon events are selected and a final result of {sigma}(Z/{gamma}*) = 327.8 {+-} 3.4(stat.) {+-} 8.4(syst.) {+-} 21.3(lumi.) pb is obtained. Correcting the number of di-muon events by a factor of 0.885 {+-} 0.015 for the contribution from pure {gamma}* exchange and Z/{gamma}* interference, the inclusive Z {yields} {mu}{sup +}{mu}{sup -} cross section is found to be: {sigma}(Z) = 290.1 {+-} 3.0(stat.) {+-} 7.4(syst.) {+-} 18.9(lumi.) pb. Finally, comparisons of W and Z boson p{sub T} distributions as measured with D0 during Run I of the Tevatron are compared to HERWIG and MC{at}NLO predictions. Relevant parameters in the simulations are tuned to obtain the best possible fit to the data. An excellent agreement is found for both HERWIG and MC{at}NLO.
The neutral current neutrino-nucleon elastic interaction {nu} N {yields} {nu} N is a fundamental process of the weak interaction ideally suited for characterizing the structure of the nucleon neutral weak current. This process comprises {approx}18% of neutrino events in the neutrino oscillation experiment, MiniBooNE, ranking it as the experiment's third largest process. Using {approx}10% of MiniBooNE's available neutrino data, a sample of these events were identified and analyzed to determine the differential cross section as a function of the momentum transfer of the interaction, Q{sup 2}. This is the first measurement of a differential cross section with MiniBooNE data. From this analysis, a value for the nucleon axial mass M{sub A} was extracted to be 1.34 {+-} 0.25 GeV consistent with previous measurements. The integrated cross section for the Q{sup 2} range 0.189 {yields} 1.13 GeV{sup 2} was calculated to be (8.8 {+-} 0.6(stat) {+-} 0.2(syst)) x 10{sup -40} cm{sup 2}.
Using the data collected with the D0 detector at {radical}s = 1.96 TeV with integrated luminosities of about 180 pb{sup -1}, we have measured the ratio of inclusive cross sections for p{bar p} {yields} Z + b-jet to p{bar p} {yields} Z + jet production. The inclusive Z + b-jet reaction is an important background to searches for the Higgs boson in associated ZH production at the Fermilab Tevatron collider and is sensitive to the b quark content of the proton. This thesis describes our measurement which is performed using the dimuon decay channel of the Z boson, i.e. Z {yields} {mu}{sup +}{mu}{sup -}. The ratio in the dimuon channel is measured to be 1.86 {+-} 0.44(stat){sub -0.28}{sup +0.24}(syst)% for hadronic jets with transverse momenta p{sub T} > 20 GeV/c and pseudorapidities |{eta}| < 2.5, consistent with next-to-leading order predictions of the standard model. This measurement is also combined with the result of the same ratio using the dielectron decay of the Z boson, and the combined measurement of the ratio of cross-sections yields 2.11 {+-} 0.41(stat){sub -0.25}{sup +0.22}(syst)%. In addition to our measurement, we also study optimization procedures for the search of Z({mu} {bar {mu}})+b{bar b} signal at D0. We demonstrate that substantial improvements in the signal sensitivity can be obtained by choosing more optimal selection cuts tailored for this signal and by combining the attributes of the similar objects in the events like muons and jets.
The direct observation of the top quark was first achieved at the Tevatron proton anti-proton collider at Fermilab. This discovery completed the third generation quark sector where the top quark is expected to accompany the bottom quark in the weak isospin doublet. This dissertation discusses the experimental verification of the production cross section as predicted by the Standard Model. A measurement of the t{bar t} production cross section using 107.9 pb{sup -1} of p{bar p} collisions at {radical}s = 1.96 TeV collected with the Collider Detector at Fermilab between March of 2003 and June of 2003 is presented. The measurement focuses on the t{bar t} production in the ''lepton plus jets'' final state in which one of the W bosons from the t{bar t} decay subsequently decays leptonically to an electron or a muon, and the other decays hadronically. The B-tagging technique which utilizes the precision silicon detector tracking is used to enhance the signal for t{bar t} events relative to the background through identification of the bottom quark from its measurable lifetime. The t{bar t} production cross section is measured to be {sigma}{sub t{bar t}} = 4.5 {+-} 1.4(stat) {+-} 0.8(sys) pb.
A preliminary measurement of the t{bar t} production cross section at {radical}s = 1.96 TeV is presented. The {mu}-plus-jets final state is analyzed in a data sample of 94 pb{sup -1} and a total of 14 events are selected with a background expectation of 11.7 {+-} 1.9 events. The measurement yields: {sigma}{sub p{bar p} {yields} t{bar t} + X} = 2.4{sub -3.5}{sup +4.2}(stat.){sub -2.6}{sup +2.5}(syst.) {+-} 0.3(lumi.) pb. The analysis, being part of a larger effort to re-observe the top quark in Tevatron Run II data and to measure the production cross section, is combined with results from all available analyses channels. The combined result yields: {sigma}{sub p{bar p}} {yields} t{bar t} + X = 8.1{sub -2.0}{sup +2.2}(stat.){sub -1.4}{sup +1.6}(syst.) {+-} 0.8(lumi.) pb.
We discuss the measurement of the cross section for t{bar t} production in p{bar p} collisions at {radical}s = 1.96 TeV in e+jets final states observed at the D0 experiment at the Fermilab Tevatron. Our result is based on data collected from the June 2002 to September 2003 period of Run II of the p{bar p} Collider. In the Standard Model, the top quark is expected to decay mainly into a W boson and a b quark. The W boson can decay subsequently into a lepton and its neutrino or a q{bar q} quark-antiquark pair. In this thesis, we focus on the e{sup +} {nu}{sub e} or e{sup -} {bar {nu}}{sub e} decays of one of the W bosons and the q{bar q} decays of the other W boson in t{bar t} final states. The b, q and q' quarks appear as jets of particles in the detector, thereby defining the e+jets final state. We present two methods used for performing this measurement. The first method is based on a Random Grid Search (RGS) that minimizes the uncertainty on the extracted cross section. The variables used in the search take advantage of differences between expected background and signal processes to obtain the yield of t{bar t} events. The second method uses a Neural Network (NN) procedure that discriminates signal from background through the application of a NN trained on simulated t{bar t} signal and W+jets background events. The preliminary results presented in this thesis for inclusive t{bar t} production are {sigma}{sub p{bar p} {yields} t{bar t} + x} of 7.9{sub -2.4}{sup +2.6}(stat) {sub -2.3}{sup +2.2}(syst) {+-} 0.5 (L) pb for the NN analysis, where the uncertainties correspond to contributions from statistical and systematic sources and from the uncertainty on luminosity. Our measurements are consistent with each other, and are within …
We have measured the top quark mass with the dynamical likelihood method. The data corresponding to an integrated luminosity of 1.7fb{sup -1} was collected in proton antiproton collisions at a center of mass energy of 1.96 TeV with the CDF detector at Fermilab Tevatron during the period March 2002-March 2007. We select t{bar t} pair production candidates by requiring one high energy lepton and four jets, in which at least one of jets must be tagged as a b-jet. In order to reconstruct the top quark mass, we use the dynamical likelihood method based on maximum likelihood method where a likelihood is defined as the differential cross section multiplied by the transfer function from observed quantities to parton quantities, as a function of the top quark mass and the jet energy scale(JES). With this method, we measure the top quark mass to be 171.6 {+-} 2.0 (stat.+ JES) {+-} 1.3(syst.) = 171.6 {+-} 2.4 GeV/c{sup 2}.
A measurement of the top quark mass with the matrix element method in the lepton + jets final state in D0 Run II is presented. Events with single isolated energetic charged lepton (electron or muon), exactly four calorimeter jets, and significant missing transverse energy are selected. Probabilities used to discriminate between signal and background are assumed to be proportional to differential cross-sections, calculated using event kinematics and folding in object resolutions and parton distribution functions. The event likelihoods constructed using these probabilities are varied with the top quark mass, m{sub t}, and the jet energy scale, JES, to give the smallest possible combined statistical + JES uncertainty.
A precise branching ratio measurement of the rare decay {pi}{sup 0} {yields} e{sup +}e{sup -} has been made. The measurement was made with the rare kaon decay experiment KTeV at Fermilab where the source of {pi}{sup 0}s was K{sub L} {yields} {pi}{sup 0}{pi}{sup 0}{pi}{sup 0} decaying in flight. A total of 794 fully reconstructed K{sub L} {yields} 3{pi}{sup 0} events consistent with two of the intermediate {pi}{sup 0}s decaying into {gamma}{gamma} and one into e{sup +}e{sup -} were collected. An estimated 53.2 {+-} 11.0 of these events were expected to be background. Normalizing to the {pi}{sup 0} Dalitz decay they found Br({pi}{sup 0} {yields} e{sup +}e{sup -}, (m{sub e{sup +}e{sup -}}/m{sub {pi}{sup 0}}){sup 2} > 0.95) = (6.44 {+-} 0.25(stat) {+-} 0.22(syst)) x 10{sup -8} where internal radiation, {pi}{sup 0} {yields} e{sup +}e{sup -}({gamma}), was limited by the requirement (m{sub e{sup +}e{sup -}}/m{sub {pi}{sup 0}}){sup 2} > 0.95 which separated it from the tree level Dalitz decay, {pi}{sup 0} {yields} e{sup +}e{sup -}P{gamma}.
A digital network of 24 seismograph stations was operated from September 15, 1987 to September 30, 1988, by Lawrence Livermore National Laboratory and Unocal as part of the Salton Sea Scientific Drilling Project to study seismicity related to tectonics and geothermal activity near the drilling site. More than 2001 microearthquakes were relocated in this study in order to image any pervasive structures that may exist within the Salton Sea geothermal field. First, detailed velocity models were obtained through standard 1-D inversion techniques. These velocity models were then used to relocate events using both single event methods and Double-Differencing, a joint hypocenter location method. An anisotropic velocity model was built from anisotropy estimates obtained from well logs within the study area. During the study period, the Superstition wills sequence occurred with two moderate earthquakes of MS 6.2 and MS 6.6. These moderate earthquakes caused a rotation of the stress field as observed from the inversion of first motion data from microearthquakes at the Salton Sea geothermal field. Coulomb failure analysis also indicates that microearthquakes occurring after the Superstition Hills sequence are located within a region of stress increase suggesting stress triggering caused by the moderate earthquakes.
The nucleon elastic electromagnetic form factors are fundamental quantities needed for an understanding of nucleon and nuclear electromagnetic structure. The evolution of the Sachs electric and magnetic form factors with Q2, the square of the four-momentum transfer, is related to the distribution of charge and magnetization within the nucleon. High precision measurements of the nucleon form factors are essential for stringent tests of our current theoretical understanding of confinement within the nucleon. Measurements of the neutron form factors, in particular, those of the neutron electric form factor, have been notoriously difficult due to the lack of a free neutron target and the vanishing integral charge of the neutron. Indeed, a precise measurement of the neutron electric form factor has eluded experimentalists for decades; however, with the advent of high duty-factor polarized electron beam facilities, experiments employing polarization degrees of freedom have finally yielded the first precise measurements of this fundamental quantity. Following a general overview of the experimental and theoretical status of the nucleon form factors, a detailed description of an experiment designed to extract the neutron electric form factor from measurements of the neutron's recoil polarization in quasielastic 2H(e, e')1H scattering is presented. The experiment described here employed the Thomas Jefferson National Accelerator Facility's longitudinally polarized electron beam, a magnetic spectrometer for detection of the scattered electron, and a neutron polarimeter designed specifically for this experiment. Measurements were conducted at three Q2 values of 0.45, 1.13, and 1.45 (GeV/c)2, and the final results extracted from an analysis of the data acquired in this experiment are reported and compared with recent theoretical predictions for the nucleon form factors.
In this thesis, both time-resolved, nonlinear optical spectroscopy and linear spectroscopy are used to investigate the interactions and dynamics of elementary excitations in strongly correlated electron systems. In the first part, we investigate the renormalization of magnetic elementary excitations in the transition metal oxide Cr{sub 2}O{sub 3}. We have created a non-equilibrium population of antiferromagnetic spin waves and characterized its dynamics, using frequency- and time-resolved optical spectroscopy of the exciton-magnon transition. We observed a time-dependent pump-probe line shape, which results from excitation induced renormalization of the spin wave band structure. We present a model that reproduces the basic characteristics of the data, in which we postulate the optical nonlinearity to be dominated by interactions with long-wavelength spin waves, and the dynamics due to spin wave thermalization. Using linear spectroscopy, coherent third-harmonic generation and pump-probe experiments, we measured the optical properties of the charge-transfer (CT) gap exciton in Sr{sub 2}CuO{sub 2}Cl{sub 2}, an undoped model compound for high-temperature superconductors. A model is developed which explains the pronounced temperature dependence and newly observed Urbach tail in the linear absorption spectrum by a strong, phonon-mediated coupling between the charge-transfer exciton and ligand field excitations of the Cu atoms. The third-order nonlinear optical susceptibility within the Cu-O plane of Sr{sub 2}CuO{sub 2}Cl{sub 2} is fully characterized in both amplitude and phase, and symmetry based conclusions are made with respect to the spatial arrangement of the underlying charge distribution. Theoretical considerations ascribe a newly reported resonance in the third-order nonlinear susceptibility at 0.7 eV to a three-photon transition from the ground state to the charge-transfer exciton. An even parity intermediate state of Cudd character, is found to contribute to the transition. Finally, preliminary results of time-resolved pump-probe spectroscopy confirm that the CT exciton or one of its constituent parts couples strongly to phonons, and we …
The High Current Experiment (HCX) at Lawrence Berkeley National Laboratory is part of the US program that explores heavy-ion beam as the driver option for fusion energy production in an Inertial Fusion Energy (IFE) plant. The HCX is a beam transport experiment at a scale representative of the low-energy end of an induction linear accelerator driver. The primary mission of this experiment is to investigate aperture fill factors acceptable for the transport of space-charge-dominated heavy-ion beams at high intensity (line charge density {approx}0.2 {micro}C/m) over long pulse durations (4 {micro}s) in alternating gradient focusing lattices of electrostatic or magnetic quadrupoles. This experiment is testing transport issues resulting from nonlinear space-charge effects and collective modes, beam centroid alignment and steering, envelope matching, image charges and focusing field nonlinearities, halo and, electron and gas cloud effects. We present the results for a coasting 1 MeV K{sup +} ion beam transported through ten electrostatic quadrupoles. The measurements cover two different fill factor studies (60% and 80% of the clear aperture radius) for which the transverse phase-space of the beam was characterized in detail, along with beam energy measurements and the first halo measurements. Electrostatic quadrupole transport at high beam fill factor ({approx}80%) is achieved with acceptable emittance growth and beam loss. We achieved good envelope control, and re-matching may only be needed every ten lattice periods (at 80% fill factor) in a longer lattice of similar design. We also show that understanding and controlling the time dependence of the envelope parameters is critical to achieving high fill factors, notably because of the injector and matching section dynamics.
This thesis reports the HAPPEX measurement of the parity-violating asymmetry for longitudinally polarized electrons elastically scattered from protons in a liquid hydrogen target. The measurement was carried out in Hall A at Thomas Jefferson National Accelerator Facility using a beam energy E = 3 GeV and scattering angle <θ{sub lab}> = 6◦. The asymmetry is sensitive to the weak neutral form factors from which we extract the strange quark electric and magnetic form factors (G{sup s}{sub E} and G{sup s}{sub M}) of the proton. The measurement was conducted during two data-taking periods in 2004 and 2005. This thesis describes the methods for controlling the helicity-correlated beam asymmetries and the analysis of the raw asymmetry. The parity-violating asymmetry has been measured to be A{sub PV} = −1.14± 0.24 (stat)±0.06 (syst) ppm at <Q{sup 2}> = 0.099 GeV{sup 2} (2004), and A{sub PV} = −1.58±0.12 (stat)±0.04 (syst) ppm at <Q{sup 2}> = 0.109 GeV{sup 2} (2005). The strange quark form factors extracted from the asymmetry are G{sup s}{sub E} + 0.080G{sup s}{sub M} = 0.030 ± 0.025 (stat) ± 0.006 (syst) ± 0.012 (FF) (2004) and G{sup s}{sub E} +0.088G{sup s}{sub M} = 0.007±0.011 (stat)±0.004 (syst)±0.005 (FF) (2005). These results place the most precise constraints on the strange quark form factors and indicate little strange dynamics in the proton.
Linear elastic fracture mechanics is widely used in industry because it established simple and explicit relationships between the permissible loading conditions and the critical crack size that is allowed in a structure. Stress intensity factors are the above-mentioned functional expressions that relate load with crack size through geometric functions or weight functions. Compliance functions are to determine the crack/flaw size in a structure when optical inspection is inconvenient. As a result, geometric functions, weight functions and compliance functions have been intensively studied to determine the stress intensity factor expressions for different geometries. However, the relations between these functions have received less attention. This work is therefore to investigate the intrinsic relationships between these functions. Theoretical derivation was carried out and the results were verified on single-edge cracked plate under tension and bending. It is found out that the geometric function is essentially the non-dimensional weight function at the loading point. The compliance function is composed of two parts: a varying part due to crack extension and a constant part from the intact structure if no crack exists. The derivative of the compliance function at any location is the product of the geometric function and the weight function at the evaluation point. Inversely, the compliance function can be acquired by the integration of the product of the geometric function and the weight function with respect to the crack size. The integral constant is just the unchanging compliance from the intact structure. Consequently, a special application of the relations is to obtain the compliance functions along a crack once the geometric function and weight functions are known. Any of the three special functions can be derived once the other two functions are known. These relations may greatly simplify the numerical process in obtaining either geometric functions, weight functions or compliance functions for …
We have searched for the Standard Model Higgs boson production in association with a W{sup {+-}} boson. This search is based on the data collected between February 2002 and May 2007, corresponding to an integrated luminosity of 1.9 fb{sup -1} collected by the Collider Detector at Fermilab (CDF) at the Tevatron which is a p{bar p} collider at a center of mass energy 1.96 TeV. W+Higgs channel is one of the most promising channels for the Higgs search at Tevatron in the low Higgs mass region (m{sub H} < 135 GeV/c{sup 2}), where Higgs boson decays into b{bar b} dominantly. The detection of lepton from the W boson decay makes the W+Higgs events much cleaner than the direct Higgs production events which have the largest production cross section. Experimentally we select events with a high p{sub T} lepton, high missing transverse energy and two b-quark jets. This signature is same as for the W+jets background which has a huge cross section. To reduce the W+jets background, b-jet identification algorithms are applied to at least one jet. The expected signal events in 1.9fb{sup -1} are 1.82 {+-} 0.15 and 1.68 {+-} 0.20 for one b-tagged events and two b-tagged events, respectively. The observed data is 805 for one b-tagged events and 173 for two b-tagged events. They are consistent with the Standard Model background expectation. After selecting the events, Neural Network (NN) discriminant technique is performed to distinguish the signal events from still residual backgrounds. We see no evidence for a Higgs signal in the dijet mass distribution and in the NN output distribution. We set a 95% confidence level upper limit on the W+Higgs production cross section times the branching ratio of the Higgs decaying into a b{bar b} pair. We obtained {sigma}(p{bar p} {yields} W{sup {+-}}H) x BR(H {yields} …
The CDF experiment has searched for production of a third generation vector leptoquark (VLQ3) in the di-tau plus di-jet channel using 322 pb{sup -1} of Run II data. We review the production and decay theory and describe the VLQ3 model we have used as a benchmark. We study the analysis, including the data sample, triggers, particle identification, and event selection. We also discuss background estimates and systematic uncertainties. We have found no evidence for VLQ3 production and have set a 95% C.L. upper limit on the pair production cross section {sigma} to 344 fb, and exclude VLQ3 in the mass range m{sub VLQ3} > 317 GeV/c{sup 2}, assuming Yang-Mills couplings and Br(LQ3 {yields} b{tau}) = 1. If theoretical uncertainties on the cross section are taken into account, the results are {sigma} < 353 fb and m{sub VLQ3} > 303 GeV/c{sup 2}. For a VLQ3 with Minimal couplings, the upper limit on the cross section is {sigma} < 493 fb ({sigma} < 554 fb) and the lower limit on the mass is m{sub VLQ3} > 251 GeV/c{sup 2} (m{sub VLQ3} > 235 GeV/c{sup 2}) for the nominal (1{sigma} varied) theoretical expectation.
All known experimental results on fundamental particles and their interactions can be described to great accuracy by a theory called the Standard Model. In the Standard Model of particle physics, the masses of particles are explained through the Higgs mechanism. The Higgs boson is the only Standard Model particle not discovered yet, and its observation or exclusion is an important test of the Standard Model. While the Standard Model predicts that a Higgs boson should exist, it does not exactly predict its mass. Direct searches have excluded a Higgs with m{sub H} < 114.4 GeV at 95% confidence level, while indirect measurements indicate that the mass should be less than 144 GeV. This analysis looks for W{sup {+-}}H {yields} {mu}{nu}{sub {mu}}b{bar b} in 1 fb{sup -1} of data collected with the D0 detector in p{bar p} collisions with {radical}s = 1.96 TeV. The analysis strategy relies on the tracking, calorimetry and muon reconstruction of the D0 experiment. The signature is a muon, missing transverse energy (E{sub T}) to account for the neutrino and two b-jets. The Higgs mass is reconstructed using the invariant mass of the two jets. Backgrounds are W{sup {+-}}b{bar b}, W{sup {+-}} c{bar c}, W{sup {+-}} + light jets (W{sup {+-}}jj) (and the corresponding backgrounds with a Z boson), t{bar t}, single top production, and QCD multijet background.
Yucca Mountain, Nevada is the proposed site of a geologic repository for the disposal of spent nuclear fuel and high-level radioactive waste in the United States. In the event repository engineered barriers fail, the saturated alluvium located south of Yucca Mountain is expected to serve as a natural barrier to the migration of radionuclides to the accessible environment. The purpose of this study is to improve the characterization of uranium retardation in the saturated zone at Yucca Mountain to support refinement of an assessment model. The distribution of uranium desorption rates from alluvium obtained from Nye County bore holes EWDP-19IM1, EWDP-10SA, EWDP-22SA were studied to address inconsistencies between results from batch sorption and column transport experiments. The alluvium and groundwater were characterized to better understand the underlying mechanisms of the observed behavior. Desorption rate constants were obtained using an activity based mass balance equation and column desorption experiments were analyzed using a mathematical model utilizing multiple sorption sites with different first-order forward and reverse reaction rates. The uranium desorption rate constants decreased over time, suggesting that the alluvium has multiple types of active sorption sites with different affinities for uranium. While a significant fraction of the initially sorbed uranium desorbed from the alluvium quite rapidly, a roughly equivalent amount remained sorbed after several months of testing. The information obtained through this research suggests that uranium may experience greater effective retardation in the alluvium than simple batch sorption experiments would suggest. Electron Probe Microanalysis shows that uranium is associated with both clay minerals and iron oxides after sorption to alluvial material. These results provide further evidence that the alluvium contains multiple sorption sites for uranium.
The purpose of this investigation was to determine the energy absorption characteristics of plastically deformed inclined struts under impact loading. This information is needed to provide a usable method by which designers and analysts of shipping casks for radioactive or fissile materials can determine the energy absorption capabilities of external longitudinal fins on cylindrical casks under specified impact conditions. A survey of technical literature related to experimental determination of the dynamic plastic behavior of struts revealed no information directly applicable to the immediate problem, especially in the impact velocity ranges desired, and an experimental program was conducted to obtain the needed data. Mild-steel struts with rectangular cross sections were impacted by free-falling weights dropped from known heights. These struts or fin specimens were inclined at five different angles to simulate different angles of impact that fins on a shipping cask could experience under certain accident conditions. The resisting force of the deforming strut was measured and recorded as a function of time by using load cells instrumented with resistance strain gage bridges, signal conditioning equipment, an oscilloscope, and a Polaroid camera. The acceleration of the impacting weight was measured and recorded as a function of time during the latter portion of the testing program by using an accelerometer attached to the drop hammer, appropriate signal conditioning equipment, the oscilloscope, and the camera. A digital computer program was prepared to numerically integrate the force-time and acceleration-time data recorded during the tests to obtain deformation-time data. The force-displacement relationships were then integrated to obtain values of absorbed energy with respect to deformation or time. The results for various fin specimen geometries and impact angles are presented graphically, and these curves may be used to compute the energy absorption capacity of a longitudinal fin on a shipping cask as a function of its …
To monitor in-flight damage and reduce life-cycle costs associated with CFRP composite aircraft, an autonomous built-in structural health monitoring (SHM) system is preferred over conventional maintenance routines and schedules. This thesis investigates the use of ultrasonic guided waves and piezoelectric transducers for the identification and localization of damage/defects occurring within critical components of CFRP composite aircraft wings, mainly the wing skin-to-spar joints. The guided wave approach for structural diagnostics was demonstrated by the dual application of active and passive monitoring techniques. For active interrogation, the guided wave propagation problem was initially studied numerically by a semi-analytical finite element method, which accounts for viscoelastic damping, in order to identify ideal mode-frequency combinations sensitive to damage occurring within CFRP bonded joints. Active guided wave tests across three representative wing skin-to-spar joints at ambient temperature were then conducted using attached Macro Fiber Composite (MFC) transducers. Results from these experiments demonstrate the importance of intelligent feature extraction for improving the sensitivity to damage. To address the widely neglected effects of temperature on guided wave base damage identification, analytical and experimental analyses were performed to characterize the influence of temperature on guided wave signal features. In addition, statistically-robust detection of simulated damage in a CFRP bonded joint was successfully achieved under changing temperature conditions through a dimensionally-low, multivariate statistical outlier analysis. The response of piezoceramic patches and MFC transducers to ultrasonic Rayleigh and Lamb wave fields was analytically derived and experimentally validated. This theory is useful for designing sensors which possess optimal sensitivity toward a given mode-frequency combination or for predicting the frequency dependent directivity patterns in a transducer's response. Based upon this theory, a novel approach was developed for passive damage and impact location in anisotropic or geometrically complex systems. The detection and location of simulated ''active'' damage or impacts was experimentally demonstrated on …
This dissertation reports on a study of search for an orbitally excited state of charmed baryons {Sigma}{sub c}{sup 0}(2800) and {Sigma}{sub c}{sup ++}(2800). They measure the widths, momentum spectrum and production cross-section for these states decaying into a {Lambda}{sub c}{sup +} and a charged {pi}. The analysis uses 230 fb{sup -1} of data collected at BABAR detector operating at PEP-II collider at Stanford Linear Accelerator Center. The data is collected in the region of {Upsilon}(4S) an {approx} 40 MeV below the resonance. {Lambda}{sub c}{sup +} baryon is reconstructed in the decay mode pK{sup -}{pi}{sup +}. The {Sigma}{sub c}(2800) baryon production at continuum is observed to be quite significant for x{sub p} > 0.7, where x{sub p} = p/{radical}E{sup 2}+M{sup 2} is the scaled momentum and varies from 0.0 to 1.0. The momentum spectrum is measured by considering the corrected yield for momentum bins above x{sub p} > 0.5 and can be parameterized very well by a Peterson function, given by: dN/dx{sub p} {proportional_to} 1/x{sub p}(1 - 1/x{sub p} - {epsilon}/1-x{sub p}){sup 2}. The values for the peterson parameter {epsilon}, are found to be 0.050 {+-} 0.010 for {Sigma}{sub c}{sup 0}(2800) and 0.057 {+-} 0.012 for {Sigma}{sub c}{sup ++}(2800). They use the momentum spectrum to evaluate the production cross-sections to be: {sigma}(e{sup +}e{sup -} {yields} {Sigma}{sub c}{sup 0}(2800)X). {Beta}({Sigma}{sub c}{sup 0}(2800) {yields} {Lambda}{sub c}{sup +}{pi}{sup -}) = 1.36 {+-} 0.42 pb and {sigma}(e{sup +}e{sup -} {yields} {Sigma}{sub c}{sup ++}(2800)X).{Beta}({Sigma}{sub c}{sup ++}(2800){yields} {Lambda}{sub c}{sup +}{pi}{sup +}) = 1.68 {+-} 0.54 pb. The authors also measure the width to be 65.6 {+-} 14.9 MeV and 67.7 {+-} 16 MeV, for the neutral and charged modes, respectively, and the corresponding observed mass differences ({Lambda}{sub c}{sup +}{pi} - {Lambda}{sub c} + 2.285), are 2.8008 {+-} 0.0023GeV/c{sup 2} and 2.7980 {+-} 0.0028GeV/c{sup 2}. The uncertainty here …
In this work the S-wave component of the K{pi} amplitude from decay of D{sup +} {yields} K{sup -}{pi}{sup +}{pi}{sup +} it is directly measured. The data come from the Fermilab E831/FOCUS experiment. The amplitude measurement is made using the partial wave analysis without any preliminary assumption about the nature of the S-wave component of the K{pi} system. The phase and magnitude of the S-wave amplitude are generic functions to be determined directly through the Dalitz plot fit. For the sake of comparison, our results the same decay is analyzed using the isobar model, which is the standard way to analyze the Dalitz plot. The data fit obtained with the partial wave analysis is better than the data fit from the isobar model. The phase variation with respect to the invariant mass K{pi} is compared with the measurement of the phase {delta}{sub I=1/2}{sup 0} (m{sub K{pi}}) from K{pi} {yields} K{pi} scattering. The difference between both analysis is discussed considering: a difference in the composition of the isospin components I = 1/2 and I = 3/2 of the K{pi} system between D{sup +} decay and the K{pi} {yields} K{pi} scattering; and the final state interaction involving all particles from decay.
MINOS (Main Injector Neutrino Oscillation Search), is a long baseline neutrino experiment designed to search for neutrino oscillations using two detectors at Fermi National Accelerator Laboratory, IL (Near Detector) and Soudan, MN (Far Detector). It will study {nu}{sub {mu}} {yields} {nu}{sub {tau}} oscillations and make a measurement on the oscillation parameters, {Delta}m{sub 23}{sup 2} and sin{sup 2} 2{theta}{sub 23}, via a {nu}{sub {mu}} beam made at Fermilab. Charge current neutrino interactions in the MINOS detectors are of three types: quasi-elastic scattering (QEL), resonance scattering (RES) and deep inelastic scattering (DIS). Of these, quasi-elastic scattering leaves the cleanest signal with just one {mu} and one proton in the final state, thus rendering the reconstruction of the neutrino energy more accurate. This thesis will outline a method to separate QEL events from the others in the two detectors and perform a calculation of {Delta}m{sub 23}{sup 2} and sin{sup 2} 2{theta}{sub 23} using those events. The period under consideration was May 2005 to February 2006. The number of observed quasi-elastic events with energies below 10 GeV was 29, where the expected number was 60 {+-} 3. A fit to the energy distribution of these events gives {Delta}m{sub 23}{sup 2} = 2.91{sub -0.53}{sup +0.49}(stat){sub -0.09}{sup +0.08}(sys) x 10{sup -3} eV{sup 2} and sin{sup 2} 2{theta}{sub 23} = 0.990{sub -0.180}(stat){sub -0.030}(sys).
Sum frequency generation (SFG), a second-order nonlinear optical process, is electric-dipole forbidden in systems with inversion symmetry. As a result, it has been used to study chiral media and interfaces, systems intrinsically lacking inversion symmetry. This thesis describes recent progresses in the applications of and new insights into SFG from chiral media and interfaces. SFG from solutions of chiral amino acids is investigated, and a theoretical model explaining the origin and the strength of the chiral signal in electronic-resonance SFG spectroscopy is discussed. An interference scheme that allows us to distinguish enantiomers by measuring both the magnitude and the phase of the chiral SFG response is described, as well as a chiral SFG microscope producing chirality-sensitive images with sub-micron resolution. Exploiting atomic and molecular parity nonconservation, the SFG process is also used to solve the Ozma problems. Sum frequency vibrational spectroscopy is used to obtain the adsorption behavior of leucine molecules at air-water interfaces. With poly(tetrafluoroethylene) as a model system, we extend the application of this surface-sensitive vibrational spectroscopy to fluorine-containing polymers.
We have demonstrated that a bulk absorber coupled to a TES can serve as a good gamma-ray spectrometer. Our measured energy resolution of 70 eV at 60 keV is among the best measurements in this field. We have also shown excellent agreement between the noise predictions and measured noise. Despite this good result, we noted that our detector design has shortcomings with a low count rate and vulnerabilities with the linearity of energy response. We addressed these issues by implementation of an active negative feedback bias. We demonstrated the effects of active bias such as additional pulse shortening, reduction of TES change in temperature during a pulse, and linearization of energy response at low energy. Linearization at higher energy is possible with optimized heat capacities and thermal conductivities of the microcalorimeter. However, the current fabrication process has low control and repeatability over the thermal properties. Thus, optimization of the detector performance is difficult until the fabrication process is improved. Currently, several efforts are underway to better control the fabrication of our gamma-ray spectrometers. We are developing a full-wafer process to produce TES films. We are investigating the thermal conductivity and surface roughness of thicker SiN membranes. We are exploring alternative methods to couple the absorber to the TES film for reproducibility. We are also optimizing the thermal conductivities within the detector to minimize two-element phonon noise. We are experimenting with different absorber materials to optimize absorption efficiency and heat capacity. We are also working on minimizing Johnson noise from the E S shunt and SQUID amplifier noise. We have shown that our performance, noise, and active bias models agree very well with measured data from several microcalorimeters. Once the fabrication improvements have been implemented, we have no doubt that our gamma-ray spectrometer will achieve even more spectacular results.
We have measured the three-body photobreakup of {sup 3}He with the tagged photon beam and the CEBAF Large Acceptance Spectrometer in Hall B at the Thomas Jefferson National Accelerator Facility, in the photon energy range between 0.35 GeV and 1.55 GeV. This measurement constitutes a wide-ranging survey of two- and three-body processes in the gamma{sup 3}He {yields} ppn reaction channel, thanks to the high statistics and large kinematic coverage obtained with the CLAS. Total and partially integrated differential cross sections for the full ppn data set and for selected kinematics were extracted and are compared to theoretical predictions of Laget (up to 1.0 GeV). At low photon energies, the calculations are generally in fair agreement with the data. The comparison shows evidence of strong contributions of three-body absorption mechanisms, especially in the star kinematics, a symmetric configuration of the three final-state nucleons. Mostly the effects of two-body absorption mechanisms are se en, as expected, in the pp-pair-breakup kinematics, where the neutron does not participate in the reaction. The quasi-two-body breakup shows angular distributions consistent with preliminary gamma{sup 3}He --> pd results, extracted from our experiment. The ratio of cross sections for the star configuration and for the two-body kinematics, shows a maximum for three-body effects at a photon energy of about 0.5 GeV, corresponding to a reduced photon wavelength of 0.4 fm. The 4pi-integrated cross section is in excellent agreement with previous experimental results from DAPHNE up to 800 MeV; no previous results have been obtained above this energy.
Precision pointing and tracking of laser beams is critical in numerous military and industrial applications. This is particularly true for systems requiring atmospheric beam propagation. Such systems are plagued by environmental influences which cause the optical signal to break up and wander. Example applications include laser communications, precision targeting, active imaging, chemical remote sensing, and laser vibrometry. The goal of this project is to build a beam steering system using a two-axis mirror to maintain precise pointing control. Ultimately, position control to 0.08% accuracy (40 {micro}rad) with a bandwidth of 200 Hz is desired. The work described encompasses evaluation of the instrumentation system and the subsequent design and implementation of an analog electronic controller for a two-axis mirror used to steer the beam. The controller operates over a wide temperature range, through multiple mirror resonances, and is independent of specific mirrors. The design was built and successfully fielded in a Lawrence Livermore National Laboratory free-space optics experiment. All measurements and performance parameters are derived from measurements made on actual hardware that was built and field tested. In some cases, specific design details have been omitted that involve proprietary information pertaining to Lawrence Livermore National Laboratory patent positions and claims. These omissions in no way impact the general validity of the work or concepts presented in this thesis.
As of the development of this thesis, no commercially available products have been identified for the digital communication of instrumented data across a thick ({approx} 6 n.) steel wall using ultrasound. The specific goal of the current research is to investigate the application of methods for digital communication of instrumented data (i.e., temperature, voltage, etc.) across the wall of a steel pressure vessel. The acoustic transmission of data using ultrasonic transducers prevents the need to breach the wall of such a pressure vessel which could ultimately affect its safety or lifespan, or void the homogeneity of an experiment under test. Actual digital communication paradigms are introduced and implemented for the successful dissemination of data across such a wall utilizing solely an acoustic ultrasonic link. The first, dubbed the ''single-hop'' configuration, can communicate bursts of digital data one-way across the wall using the Differential Binary Phase-Shift Keying (DBPSK) modulation technique as fast as 500 bps. The second, dubbed the ''double-hop'' configuration, transmits a carrier into the vessel, modulates it, and retransmits it externally. Using a pulsed carrier with Pulse Amplitude Modulation (PAM), this technique can communicate digital data as fast as 500 bps. Using a CW carrier, Least Mean-Squared (LMS) adaptive interference suppression, and DBPSK, this method can communicate data as fast as 5 kbps. A third technique, dubbed the ''reflected-power'' configuration, communicates digital data by modulating a pulsed carrier by varying the acoustic impedance at the internal transducer-wall interface. The paradigms of the latter two configurations are believed to be unique. All modulation methods are based on the premise that the wall cannot be breached in any way and can therefore be viably implemented with power delivered wirelessly through the acoustic channel using ultrasound. Methods, results, and considerations for future research are discussed herein.
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