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 Title
 Adaptation of UltraPrecise Atomic Mass Measurement Techniques to Microwave Spectroscopy on a Single Molecular Ion by Detecting Polarizability Shifts in a Penning Trap.
 Creator

Zarrella, Andrew, Physics
 Abstract/Description

Using the FSU Ion Penning trap it is possible to measure the ratio of the cyclotron frequencies of two molecular ions to a precision of 0.1 ppb. These cyclotron frequencies can be shifted due to large electric polarizabilities in some molecular ions. Because the polarizability of the molecular ion is dependent on the quantized rotational levels of the molecule, is possible to use the cyclotron frequency shifts detected in our lab to detect transitions between rotational levels. This allows us...
Show moreUsing the FSU Ion Penning trap it is possible to measure the ratio of the cyclotron frequencies of two molecular ions to a precision of 0.1 ppb. These cyclotron frequencies can be shifted due to large electric polarizabilities in some molecular ions. Because the polarizability of the molecular ion is dependent on the quantized rotational levels of the molecule, is possible to use the cyclotron frequency shifts detected in our lab to detect transitions between rotational levels. This allows us to do microwave spectroscopy on single molecular ions. The main goal of this project will be to implement this new method of microwave spectroscopy, by measuring the lambdatype doubling splitting of the diatomic molecular ion, NH+, in its vibrational and rotational ground state.
Show less  Date Issued
 2011
 Identifier
 FSU_migr_uhm0043
 Format
 Thesis
 Title
 Digitally Controlled Four Harmonic Buncher for FSU LINAC.
 Creator

Moerland, Daniel, Physics
 Abstract/Description

Florida State University's John D. Fox Superconducting Accelerator Laboratory is operating a TandemLINAC system for heavy ion beams at energies of 510 MeV/u. Recently, the accelerator has been used as the driver for the radioactive beam facility RESOLUT, which poses new demands on its highintensity performance and timeresolution. These demands motivated us to optimize the RF bunching system and to switch the bunch frequency from 48.5 to 12.125MHz. We installed a fourharmonic resonant...
Show moreFlorida State University's John D. Fox Superconducting Accelerator Laboratory is operating a TandemLINAC system for heavy ion beams at energies of 510 MeV/u. Recently, the accelerator has been used as the driver for the radioactive beam facility RESOLUT, which poses new demands on its highintensity performance and timeresolution. These demands motivated us to optimize the RF bunching system and to switch the bunch frequency from 48.5 to 12.125MHz. We installed a fourharmonic resonant transformer to create 34 kV potential oscillations across a pair of wiremesh grids. This setup is modulating the energy of the beam injected into the tandem accelerator, with the aim to create short bunches of beam particles. A sawtoothlike waveform is created using the Fourier series method, by combining the basis sinusoidal wave of 12.125MHz and its 3 higher order harmonics, in a manner similar to the systems used at ATLAS [1] and other RFaccelerators. A new aspect of our setup is the use of a digital 1GHz function generator, which allows us to optimize and stabilize the synthesized waveform. The control system was realized using Labview [2] and integrated into the recently updated controls of the accelerator. We characterize the bunching quality achieved and discuss the optimization of the bunching waveform. The bunching system has been successfully used in a number of LINACexperiments performed during 2011 and 2012.
Show less  Date Issued
 2012
 Identifier
 FSU_migr_uhm0106
 Format
 Thesis
 Title
 Domain Coarsening in the Hyperbolic Plane.
 Creator

Raffield, Jesse, Department of Physics
 Abstract/Description

Since the simplest case was solved exactly by Onsager in 1944, the twodimensional Ising model has become one of the most studied models in statistical physics. Despite its simplicity, it has found applications in research ranging from condensed matter physics to biology. Our research focused on an interesting variant of this model that lives within an area of negative Gaussian curvature instead of traditional Euclidean space. Specifically, a series of MonteCarlo simulations were conducted...
Show moreSince the simplest case was solved exactly by Onsager in 1944, the twodimensional Ising model has become one of the most studied models in statistical physics. Despite its simplicity, it has found applications in research ranging from condensed matter physics to biology. Our research focused on an interesting variant of this model that lives within an area of negative Gaussian curvature instead of traditional Euclidean space. Specifically, a series of MonteCarlo simulations were conducted to analyze how domains within the model coarsen as a function of time. In the Euclidean model, the feature size goes as t1/3<\sup>, which is close to our results on two of the Euclidean lattices, but for our model on a hyperbolic lattice the characteristic growth exponent was found to be much lower, approximately 0.13.
Show less  Date Issued
 2013
 Identifier
 FSU_migr_uhm0199
 Format
 Thesis
 Title
 An Exploration into the Photoproduction of ProtonAntiproton Pairs.
 Creator

Morales, Peter, Physics
 Abstract/Description

The research focus of this report is an analysis on the reaction γp→ppp̄, for photon energy in the range 4.8 to 5.5 GeV. The purpose of this study is to gain a greater understanding of the processes behind the photoproduction of protonantiproton pairs. Research was performed on data collected from the g12 experiment conducted at Jefferson National Laboratory Accelerator Facility. Data from the experiment was mined and formatted for analysis in the ROOT framework. Cuts were made to the data...
Show moreThe research focus of this report is an analysis on the reaction γp→ppp̄, for photon energy in the range 4.8 to 5.5 GeV. The purpose of this study is to gain a greater understanding of the processes behind the photoproduction of protonantiproton pairs. Research was performed on data collected from the g12 experiment conducted at Jefferson National Laboratory Accelerator Facility. Data from the experiment was mined and formatted for analysis in the ROOT framework. Cuts were made to the data to ensure events had protons with welldefined momenta and minimal background. A total of 20,927 events were observed. Invariant mass plots were generated from the selected data for each proton and antiproton in order to search for intermediate resonances that might decay to a protonantiproton pair. There were no significant signs of narrow resonances found in the final data. However, the possibility for broader resonances is not completely left out.
Show less  Date Issued
 2012
 Identifier
 FSU_migr_uhm0073
 Format
 Thesis
 Title
 Exploratory Studies of the Photoproduced π°η Channel and Determination of Preliminary Cross Sections.
 Creator

Woodard, Anna
 Abstract/Description

The Crystal Barrel detector is an ideal instrument to study multiphoton final states due to its large solid angle coverage and excellent photon detection efficiency. In this study, preliminary differential cross sections of the reaction γp → Δη→ pπ°η were extracted from data taken while the Crystal Barrel was configured with the TAPS calorimeter positioned in the forward direction. Approximately 186,000 pπ°η events were identified. Trigger efficiencies and energy thresholds in the TAPS...
Show moreThe Crystal Barrel detector is an ideal instrument to study multiphoton final states due to its large solid angle coverage and excellent photon detection efficiency. In this study, preliminary differential cross sections of the reaction γp → Δη→ pπ°η were extracted from data taken while the Crystal Barrel was configured with the TAPS calorimeter positioned in the forward direction. Approximately 186,000 pπ°η events were identified. Trigger efficiencies and energy thresholds in the TAPS calorimeter were studied. Events were reconstructed using a missing proton kinematic fit and the pπ°η final state was selected via a series of confidence level cuts. pπ°η events were classified according to incoming photon energy Eγ and scattering angle θηcm of the η meson in the centerofmass system. Invariant mass spectra for the p_0 combinations (Eγ, cos θηcm) were plotted. Existing Monte Carlo (MC) software was used to simulate the experimental setup and generate the expected mass spectra, corrected for phasespace and relativistic effects, for major contributing channels. A root C interpreter script was written to determine the Δ reaction yields as a function of the incoming photon energy and scattering angle. This was accomplished by using the roofit modeling toolkit to generate probability density functions (PDFs) from the MC. The pπ° spectra were then fitted with a sum of MC PDFs for the two largest isobar contributions, Δ+(1232)π and N(1535)S11η. The pπ° spectra indicate dominant Δ production in the threshold region. At higher energies the S11 contribution increases; the development of a second peak besides the Δ becomes visible around 1550 MeV. Above 1800 MeV, S11 production is comparable in intensity to the Δ. An unambiguous angular dependence for the S11 is observed over the full Eγ range as production drops off rapidly at forward angles. The fit procedure is more accurate at higher energies, where Δ and S11 production are well separated, and two clear peaks exist. It is likely that at lower energies the background under the Δ peak was underestimated. Preliminary differential cross sections for γp → Δη → pπ°η were calculated from the Δ yields and are presented here along with an interpretation of major features. First results forthe total γp → pπ°η and γp → pπ°π° cross sections are included. Agreement with previous studies is fair. Possible explanations for discrepancies are discussed.
Show less  Date Issued
 2008
 Identifier
 FSU_migr_uhm0045
 Format
 Thesis
 Title
 Finite Lattice Size Corrections The EnergyMomentum Dispersion.
 Creator

McDargh, Zachary, Physics
 Abstract/Description

Lattice Gauge Theory (LGT) describes gauge and matter fields on a discrete Euclidian spacetime lattice. Due to the finite spacing between the lattice points, there is a builtin ultraviolet energy cutoff. Additionally, there is an infrared energy cutoff in computer simulations due to the finite size of the lattice. With these approximations, the energymomentum dispersion becomes modified. In this thesis, we study the recovery of the continuous energymomentum dispersion. We perform fits of...
Show moreLattice Gauge Theory (LGT) describes gauge and matter fields on a discrete Euclidian spacetime lattice. Due to the finite spacing between the lattice points, there is a builtin ultraviolet energy cutoff. Additionally, there is an infrared energy cutoff in computer simulations due to the finite size of the lattice. With these approximations, the energymomentum dispersion becomes modified. In this thesis, we study the recovery of the continuous energymomentum dispersion. We perform fits of the correlation function fromMarkov ChainMonte Carlo (MCMC) simulations for various lattice sizes and spacings for a freescalar field and for an Abelian U(1) gauge field. For the scalar field, we also vary the mass of the particles; for U(1) LGT, we vary the coupling constant β. These fits return the energy of a particle at definite momentum, from which the mass can be recovered using the energymomentum dispersion. It is found that the finitesize effect in MCMC calculations decreases as exp(−N), where N is the space dimension of the lattice. Furthermore, the effect is more significant for larger masses (scalar field) and coupling constant values near the phase transition βc = 1.01 (U(1) LGT).
Show less  Date Issued
 2012
 Identifier
 FSU_migr_uhm0047
 Format
 Thesis
 Title
 Lagrange Meshes in Hardronic Physics.
 Creator

Bryant, Brandon, Physics
 Abstract/Description

In hadronic physics, the potentials of hadrons are not known and, therefore, their wave functions are not known either. The wave functions can be used to calculate energy spectra and other properties of hadrons, like decay rates. Some hadronic physicists resort to approximation methods to describe the wave functions. In this project, we express wave functions as expansions of basis functions that contain orthogonal polynomials and then employ them in a variational method. We apply this...
Show moreIn hadronic physics, the potentials of hadrons are not known and, therefore, their wave functions are not known either. The wave functions can be used to calculate energy spectra and other properties of hadrons, like decay rates. Some hadronic physicists resort to approximation methods to describe the wave functions. In this project, we express wave functions as expansions of basis functions that contain orthogonal polynomials and then employ them in a variational method. We apply this technique to 2 different systems with known wave functions for 2 different bases. We find that with an appropriately chosen basis of sufficient size this technique produces accurate wave functions and energy spectra. Choosing a sufficiently large basis becomes problematic in practice because of the computational time required to perform eigenvalue calculations. It is desirable then to employ an efficient means of computation. We address this issue by use of the Lagrange mesh method. This method is an approximate variational calculation that gives a potential matrix which is diagonal and a kinetic matrix that must only be calculated once for a given basis. Furthermore, each nonzero element in the potential matrix requires evaluation at only 1 mesh point and each element in the kinetic matrix requires evaluation at only 1 or 2 mesh points. We apply the Lagrange mesh method to a problem with an exact, known solution and then to a hadronic problem. We find that this method is easily implemented and gives accurate results.
Show less  Date Issued
 2011
 Identifier
 FSU_migr_uhm0006
 Format
 Thesis
 Title
 Lagrange Meshes in Nuclear Physics.
 Creator

Hynds, Taylor, Department of Physics
 Abstract/Description

We examine different methods of solving the Schroedinger equation for two and threebody systems. We begin by constructing variational wave functions as expansions in a basis of orthogonal polynomials. This method has been found to give accurate results, given a sufficiently large basis. However, computationally this can become very cumbersome. We therefore employ the Lagrangemesh method, which leads to a simple calculation of both potential and kinetic matrix elements that is both...
Show moreWe examine different methods of solving the Schroedinger equation for two and threebody systems. We begin by constructing variational wave functions as expansions in a basis of orthogonal polynomials. This method has been found to give accurate results, given a sufficiently large basis. However, computationally this can become very cumbersome. We therefore employ the Lagrangemesh method, which leads to a simple calculation of both potential and kinetic matrix elements that is both computationally efficient and results in little to no loss in accuracy. This method has been applied to several problems with well known analytical solutions, and has given excellent results. We demonstrate the efficacy of this method in analyzing nuclear systems.
Show less  Date Issued
 2013
 Identifier
 FSU_migr_uhm0177
 Format
 Thesis
 Title
 Meson Spectroscopy: γp>Λ^0 K^+ π^+ π^ Simulated Photoproduction of Strange Mesons.
 Creator

Norris, John, Department of Physics
 Abstract/Description

The goal of this project was to simulate a small scale experiment in meson spectroscopy involving the photoproduction of strange mesons according to: . The decay channels selected for study consisted of the final state topologies: and where the brackets denote a particle is allowed to go undetected. The theory behind the process predicts that when the 9 GeV photon is incident on the target proton (quark content udu), there is a resulting pair production and exchange of a strange quark and...
Show moreThe goal of this project was to simulate a small scale experiment in meson spectroscopy involving the photoproduction of strange mesons according to: . The decay channels selected for study consisted of the final state topologies: and where the brackets denote a particle is allowed to go undetected. The theory behind the process predicts that when the 9 GeV photon is incident on the target proton (quark content udu), there is a resulting pair production and exchange of a strange quark and antiquark. This interaction results in the formation of a recoil baryon (uds), and an (unobserved) excited Kaon system ( us(bar) ). These systems then decay and the products of these decays are used to study the physics of the interaction. In order to accomplish this task, a Monte Carlo simulation program was employed to generate phase space events corresponding to the end state topologies produced via the subsequent decays of these two systems. The resulting 1,003,648 simulated events consisting solely of particle 4vectors which were then processed by a number of different software utilities to further simulate the effects of propagation through and interaction with the virtual detector array; as well as to introduce additional background events which are an inevitable consequence of any real experimental setup. The resultant fully processed events were then reconstructed and processed by an analysis software program, employing a unique analysis plugin written specifically for this project, currently under development for use in the GlueX experiment being conducted at Jefferson Labs in Virginia. The acceptances that resulted from the above procedures were found to initially be 7.25% for the 5 particle state and 26.93% for the missing state, which is consistent with current estimates. However the subsequent kinematic fitting reduced these values to 1.27% and 4.59%, respectively, indicating there is still an issue in this part of the software. Once the acceptances had been generated, the phase spaces of both reactions were fully mapped out by means of invariant mass spectra.
Show less  Date Issued
 2014
 Identifier
 FSU_migr_uhm0421
 Format
 Thesis
 Title
 Monte Carlo Simulations for Future Geoneutrino Detectors.
 Creator

Askins, Morgan, Physics
 Abstract/Description

The main contribution of heat in the earth's mantle is thought to be the radioactive decays of 238U, 232Th, and 40K decay series. A precise measurement of the levels of 238U and 232Th can be determined by measuring the flux of ve (geoneutrinos) emitted from their decay chains. Although detectors such as kamLAND and Borexino have detected few geoneutrinos, a new cost effective geoneutrino detector is proposed which takes advantage of the total internal re ection within a long rectangular prism...
Show moreThe main contribution of heat in the earth's mantle is thought to be the radioactive decays of 238U, 232Th, and 40K decay series. A precise measurement of the levels of 238U and 232Th can be determined by measuring the flux of ve (geoneutrinos) emitted from their decay chains. Although detectors such as kamLAND and Borexino have detected few geoneutrinos, a new cost effective geoneutrino detector is proposed which takes advantage of the total internal re ection within a long rectangular prism acrylic container of liquid scintillator having a single photomultiplier tube (PMT) on each end. An array of these containers would allow for a large scintillator volume relative to the number of PMTs, but a design with such a large ratio of arcylic to scintillator may suffer from a larger background from naturally occurring 238U and 232Th within the acrylic. The event signatures of these decays were compared to those from neutrino interactions using RAT, a Monte Carlo simulation software based upon GEANT4. Implimentation of detector design allowed for cuts in background decays from the detector to be made such that 93% of the background 238U and 86% of the background 232Th decay series are removed. The overall loss of neutrino events from these cuts is about 36%.
Show less  Date Issued
 2011
 Identifier
 FSU_migr_uhm0003
 Format
 Thesis
 Title
 Network Theoretical Approaches to Partitioning of Red Power Grids.
 Creator

Israels, Brett, Department of Physics
 Abstract/Description

Power grids are innately susceptible to electrical faults. Here we present divisive and agglomerative networktheoretical approaches to achieve intentional intelligent islanding of a power grid in order to limit cascading power failures in case a fault occurs. A power grid is modeled here as a network consisting of nodes and edges. The various methods we use are designed to partition a power grid network into smaller communities of noes with local generating capacity (islands). Here we...
Show morePower grids are innately susceptible to electrical faults. Here we present divisive and agglomerative networktheoretical approaches to achieve intentional intelligent islanding of a power grid in order to limit cascading power failures in case a fault occurs. A power grid is modeled here as a network consisting of nodes and edges. The various methods we use are designed to partition a power grid network into smaller communities of noes with local generating capacity (islands). Here we discuss results of using spectral matrix methods along with Monte Carlo methods to analyze and partition an illustrative example network, as well as the Floridian power grid, and the power distribution system for a conceptual allelectric naval vessel. We also contrast the effects of approximating the generating capacity of generators according to their degrees versus using their actual generating capacities. Finally, we propose an implementation strategy as well as possible directions for future study.
Show less  Date Issued
 2012
 Identifier
 FSU_migr_uhm0110
 Format
 Thesis
 Title
 Onchip Cavities for Magnetic Resonance Studies.
 Creator

Serniak, Kyle, Department of Physics
 Abstract/Description

The control of dynamics of spins in solidstate materials has direct implications at both fundamental and applied levels. Research topics, in particular quantum computing, rely heavily on both complex control techniques and long spin coherence times to achieve intricate and robust information control. A natural way of driving spin orientation is by using electromagnetic fields (photons) and it can be done either as a classical rotation or by entanglement with the field itself. We are focusing...
Show moreThe control of dynamics of spins in solidstate materials has direct implications at both fundamental and applied levels. Research topics, in particular quantum computing, rely heavily on both complex control techniques and long spin coherence times to achieve intricate and robust information control. A natural way of driving spin orientation is by using electromagnetic fields (photons) and it can be done either as a classical rotation or by entanglement with the field itself. We are focusing on implementing such techniques in solidstate systems containing diluted, highly coherent spins. The goal of this project is to design and implement an innovative setup for electron spin resonance spectroscopy (ESR) using onchip coplanar waveguide resonant cavities. Onchip cavity designs, such as microstrips, have been attracting interest as of late due to their high sensitivities and low noise baselines, which makes them particularly well suited for studying small, dilute spin samples. [3, 4] Through simulations we aim to optimize coupling gap parameters and maximize the quality factor of the cavity resonances in a nearly ideal system. Cavities were fabricated by photolithography and electron beam evaporation techniques at NHMFL, and their transmission properties were studied at 4.2 K and 15 mK. Future studies will include the fabrication of silver, aluminum, and niobium cavities of varying thickness and testing of cavity eï¬ectiveness in an ESR setup utilizing a dilution refrigerator.
Show less  Date Issued
 2013
 Identifier
 FSU_migr_uhm0183
 Format
 Thesis
 Title
 Photomechanical Responses in Polymerized Azobenzene and Application to Heliostats.
 Creator

Roberts, Dennice, Department of Physics
 Abstract/Description

The search for viable forms of alternative energy has been a topic of recent research, and harvesting of solar energy has already been realized in various forms. Certain compounds have been shown to have visible physical responses when hit with light, transforming optical energy into motion. This project aims to better characterize properties of azobenzene, one such polymeric photomechanical actuator by considering it under various conditions of incident LED light. While much previous...
Show moreThe search for viable forms of alternative energy has been a topic of recent research, and harvesting of solar energy has already been realized in various forms. Certain compounds have been shown to have visible physical responses when hit with light, transforming optical energy into motion. This project aims to better characterize properties of azobenzene, one such polymeric photomechanical actuator by considering it under various conditions of incident LED light. While much previous research has been done on azobenzene polymerized in a polyacrylate, this project holds its focus on an azobenzenedoped polyimide compound. It also attempts to understand the role this smart material may play in solar heliostats. The movement of these apparati is usually controlled by electromagnetic motors, but could instead be moved using azobenzene as a photonpowered motor that does work on the polymer network.
Show less  Date Issued
 2014
 Identifier
 FSU_migr_uhm0367
 Format
 Thesis
 Title
 A Quantum Compiler for Topological Quantum Computation.
 Creator

Carnahan, Caitlin, Physics
 Abstract/Description

A quantum computer is a device that exploits the strange properties of quantum mechanics in order to perform computations that are not feasible on a classical computer. To implement a quantum computer, it will be necessary to maintain the delicate quantum superpositions formed during computation; this is a very difficult problem because quantum systems, by their very nature, are incredibly fragile. However, it is possible to implement a finite of quantum gates to the required accuracy, which...
Show moreA quantum computer is a device that exploits the strange properties of quantum mechanics in order to perform computations that are not feasible on a classical computer. To implement a quantum computer, it will be necessary to maintain the delicate quantum superpositions formed during computation; this is a very difficult problem because quantum systems, by their very nature, are incredibly fragile. However, it is possible to implement a finite of quantum gates to the required accuracy, which makes it possible to perform faulttolerant quantum computing, a scheme that minimizes error propagation in computations. The problem then becomes developing a method to build arbitrary quantum operations using this finite set of faulttolerant gates. This can be accomplished by using the SolovayKitaev theorem, which proves that any unitary operation can not only be simulated, but done so efficiently to within a small margin of approximation using only the gates in the universal faulttolerant gate set. The purpose of this research is to create an efficient program that demonstrates the process of the SolovayKitaev theorem using various universal gate sets. Essentially, the program presented in this paper translates a desired operation into the "machine code" of a quantum computer and therefore acts as a "quantum compiler". This project focuses specifically on topological quantum computing in which the faulttolerant gate set can be visualized as elementary braids formed by worldlines traced out by exotic quasiparticles known as Fibonacci anyons.
Show less  Date Issued
 2012
 Identifier
 FSU_migr_uhm0096
 Format
 Thesis
 Title
 The SelfDual Nonlinear Schrödinger Equation: Properties and Dynamics.
 Creator

Pawlak, Kelly, Department of Physics
 Abstract/Description

We introduce a new nonlinear equation, the SelfDual Nonlinear Schrödinger Equation (SDNLS) which resembles the GrossPitaevskii Equation [6] [4]. Unique to the SDNLS is its invariance under the Fourier transform — a form of duality which is reflected in systems such as the quantum harmonic oscillator. In this paper we explore various properties of the equation, starting with two proposed derivations based on known physics. We have managed to find a set of analytic timeindependent solutions...
Show moreWe introduce a new nonlinear equation, the SelfDual Nonlinear Schrödinger Equation (SDNLS) which resembles the GrossPitaevskii Equation [6] [4]. Unique to the SDNLS is its invariance under the Fourier transform — a form of duality which is reflected in systems such as the quantum harmonic oscillator. In this paper we explore various properties of the equation, starting with two proposed derivations based on known physics. We have managed to find a set of analytic timeindependent solutions as well as a set of dynamical ones, which are presented in the paper. In addition to these we explore numerical solutions and comment on the qualitative behavior of these solutions in different parameter regimes. Finally, we make remarks regarding the future study of this equation. This thesis reflects a portion of a manuscript soon to be submitted to Physical Review A, entitled "SelfDual Nonlocal Nonlinear Schrödinger Equation" in the upcoming months.
Show less  Date Issued
 2014
 Identifier
 FSU_migr_uhm0335
 Format
 Thesis
 Title
 Synthesis and Characterization of SN Doped CEIN3.
 Creator

Collar, Kristen, Physics
 Abstract/Description

CeIn3 is a cubic antiferromagnetic heavy fermion metal that orders with a Néel temperature of 10.1K at zero magnetic field. It requires fields up to 64T in order to see the Néel transition and the modified Lifshitz transition[1,2]; however, low dopings of tin have been shown to greatly reduce the Néel transition to occur at lower magnetic fields[3]. CeIn3xSnx (x=0.25, 0.50, 0.75) were grown using a flux growth technique to investigate the magnetic transitions in lower fields. Crystal...
Show moreCeIn3 is a cubic antiferromagnetic heavy fermion metal that orders with a Néel temperature of 10.1K at zero magnetic field. It requires fields up to 64T in order to see the Néel transition and the modified Lifshitz transition[1,2]; however, low dopings of tin have been shown to greatly reduce the Néel transition to occur at lower magnetic fields[3]. CeIn3xSnx (x=0.25, 0.50, 0.75) were grown using a flux growth technique to investigate the magnetic transitions in lower fields. Crystal analysis was conducted using SEM/EDS, which estimated the atomic percentages of the elements in the compound to quantify the amount of tin that was incorporated into each crystal. The crystals were characterized using torque magnetometry in the Physical Property Measurement System (PPMS) in order to observe de Haasvan Alphen (dHvA) quantum oscillations. The dHvA oscillations observed in the CeIn3 yielded frequencies which correspond to the Landau levels being excited past the Fermi energy. The frequencies were found using a fast fourier transform. They were confirmed to be the same frequencies seen in published data [4], which verifies that this method of flux growth has the potential to grow clean single crystals. No oscillations were observed in the tin doped samples. It was concluded that the sample doping levels were too high and acted as a contaminant, preventing the dHvA oscillations from being observed. The search for an optimum doping continues with lower doping concentrations being grown.
Show less  Date Issued
 2011
 Identifier
 FSU_migr_uhm0007
 Format
 Thesis
 Title
 Validating MonteCarlo Distributions in the Search for the Higgs Boson.
 Creator

Ackert, Andrew, Physics
 Abstract/Description

The goal of this research was to develop a method of validating multiparameter Monte Carlo (MC) simulations. These simulations mimic the protonproton collisions at the Large Hadron Collider (LHC) that are being used to search for the Higgs boson. The basic idea is to construct partitions, count the number of data points that lie within each partition, and apply the partition and counting procedures to both collision data from the LHC and data created via MonteCarlo simulations. In...
Show moreThe goal of this research was to develop a method of validating multiparameter Monte Carlo (MC) simulations. These simulations mimic the protonproton collisions at the Large Hadron Collider (LHC) that are being used to search for the Higgs boson. The basic idea is to construct partitions, count the number of data points that lie within each partition, and apply the partition and counting procedures to both collision data from the LHC and data created via MonteCarlo simulations. In principle, the method developed can be used with any measure of dissimilarity between distributions with any number of parameters. In this study, we used Fisher's test (Ftest) applied to 2 parameters of the data (btag and dimuon mass). Through the Ftest it was concluded that, at least in these 2 parameters, the LHC data and the MC data were in agreement.
Show less  Date Issued
 2012
 Identifier
 FSU_migr_uhm0104
 Format
 Thesis