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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
 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
 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
 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
 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
 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