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Full-Text Articles in Physics
Analysis, Prototyping, And Design Of An Ionization Profile Monitor For The Spallation Neutron Source Accumulator Ring, Dirk A. Bartkoski
Analysis, Prototyping, And Design Of An Ionization Profile Monitor For The Spallation Neutron Source Accumulator Ring, Dirk A. Bartkoski
Doctoral Dissertations
The Spallation Neutron Source (SNS) located in the Oak Ridge National Laboratory is comprised of a 1 GeV linear H- [H^-] accelerator followed by an accumulator ring that delivers high intensity 1 μs [microsecond] long pulses of 1.5x1014 [1.5x10^14] protons to a liquid mercury target for neutron production by spallation reaction. With its strict 0.01% total beam loss condition, planned power upgrade, and proposed second target station, SNS ring beam-profile diagnostics capable of monitoring evolving beam conditions during high-power conditions are crucial for efficient operation and improvement. By subjecting ionized electrons created during beam interactions with the residual …
Measurement Of [Special Characters Omitted] (Pp[Special Characters Omitted]Tt) In The[Special Characters Omitted]+ Jets Channel Using 4.7 Fb-1 Of Data From The Atlas Experiment Of The Large Hadron Collider, Anirvan Sircar
Doctoral Dissertations
The top quark is the heaviest of the known elementary particles in the Standard Model. Top quark decay can result into various final states; therefore, careful study of its production rate and other properties is very important for particle physics. With the shutdown of the Tevatron, The Large Hadron Collider (LHC) is the only facility currently capable of studying top quark properties. The data obtained by proton-proton collisions in the LHC is recorded by two general purpose detectors, ATLAS and CMS. The results in the dissertation are from the ATLAS detector. A new measurement is reported of &sgr;(pp [special …
Generalized Finite-Difference Time-Domain Schemes For Solving Nonlinear Schrödinger Equations, Frederick Ira Moxley Iii
Generalized Finite-Difference Time-Domain Schemes For Solving Nonlinear Schrödinger Equations, Frederick Ira Moxley Iii
Doctoral Dissertations
The nonlinear Schrödinger equation (NLSE) is one of the most widely applicable equations in physical science, and characterizes nonlinear dispersive waves, optics, water waves, and the dynamics of molecules. The NLSE satisfies many mathematical conservation laws. Moreover, due to the nonlinearity, the NLSE often requires a numerical solution, which also satisfies the conservation laws. Some of the more popular numerical methods for solving the NLSE include the finite difference, finite element, and spectral methods such as the pseudospectral, split-step with Fourier transform, and integrating factor coupled with a Fourier transform. With regard to the finite difference and finite element methods, …
Quantitative Techniques For Pet/Ct: A Clinical Assessment Of The Impact Of Psf And Tof, Joshua Donald Schaefferkoetter
Quantitative Techniques For Pet/Ct: A Clinical Assessment Of The Impact Of Psf And Tof, Joshua Donald Schaefferkoetter
Doctoral Dissertations
Tomographic reconstruction has been a challenge for many imaging applications, and it is particularly problematic for count-limited modalities such as Positron Emission Tomography (PET). Recent advances in PET, including the incorporation of time-of-flight (TOF) information and modeling the variation of the point response across the imaging field (PSF), have resulted in significant improvements in image quality. While the effects of these techniques have been characterized with simulations and mathematical modeling, there has been relatively little work investigating the potential impact of such methods in the clinical setting. The objective of this work is to quantify these techniques in the context …