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ContributorsKierum, Caitlin (Contributor) / Novak, Gail (Pianist) (Performer) / Liang, Jack (Performer) / ASU Library. Music Library (Publisher)
Created2018-04-11
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Description

An X class solar flare has the potential to remove our satellites from orbit, permanently deactivate our main forms of communication and bring humanity into a technology-free age. By using Geant4, it is possible to simulate several layers of the Earth's atmosphere and send a simulated solar flare and coronal

An X class solar flare has the potential to remove our satellites from orbit, permanently deactivate our main forms of communication and bring humanity into a technology-free age. By using Geant4, it is possible to simulate several layers of the Earth's atmosphere and send a simulated solar flare and coronal mass ejection. This thesis will show the interaction of photons and protons of various energies with several kilometers of atmosphere.

ContributorsDolghier, Kristian Adrian (Author) / Shovkovy, Igor (Thesis director) / Steinkamp, Brian (Committee member) / Economics Program in CLAS (Contributor) / College of Integrative Sciences and Arts (Contributor, Contributor) / Barrett, The Honors College (Contributor)
Created2021-05
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Description
The nucleon resonance spectrum consists of many overlapping excitations. Polarization observables are an important tool for understanding and clarifying these spectra. While there is a large data base of differential cross sections for the process, very few data exist for polarization observables. A program of double polarization experiments has been

The nucleon resonance spectrum consists of many overlapping excitations. Polarization observables are an important tool for understanding and clarifying these spectra. While there is a large data base of differential cross sections for the process, very few data exist for polarization observables. A program of double polarization experiments has been conducted at Jefferson Lab using a tagged polarized photon beam and a frozen spin polarized target (FROST). The results presented here were taken during the first running period of FROST using the CLAS detector at Jefferson Lab with photon energies ranging from 329 MeV to 2.35 GeV. Data are presented for the E polarization observable for eta meson photoproduction on the proton from threshold (W=1500 MeV) to W=1900 MeV. Comparisons to the partial wave analyses of SAID and Bonn-Gatchina along with the isobar analysis of eta-MAID are made. These results will help distinguish between current theoretical predictions and refine future theories.
ContributorsMorrison, Brian (Author) / Ritchie, Barry (Thesis advisor) / Dugger, Michael (Committee member) / Shovkovy, Igor (Committee member) / Davies, Paul (Committee member) / Alarcon, Ricardo (Committee member) / Arizona State University (Publisher)
Created2011
ContributorsLougheed, Julia (Performer) / Novak, Gail (Pianist) (Performer) / Bayer, Elizabeth Kennedy (Performer) / Clifton-Armenta, Tyler (Performer) / Park, Julie (Performer) / Javier de Alba, Francisco (Performer) / Vientos Dulces (Performer) / ASU Library. Music Library (Publisher)
Created2018-04-07
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Description
Monte Carlo methods often used in nuclear physics, such as auxiliary field diffusion Monte Carlo and Green's function Monte Carlo, have typically relied on phenomenological local real-space potentials containing as few derivatives as possible, such as the Argonne-Urbana family of interactions, to make sampling simple and efficient. Basis set methods

Monte Carlo methods often used in nuclear physics, such as auxiliary field diffusion Monte Carlo and Green's function Monte Carlo, have typically relied on phenomenological local real-space potentials containing as few derivatives as possible, such as the Argonne-Urbana family of interactions, to make sampling simple and efficient. Basis set methods such as no-core shell model or coupled-cluster techniques typically use softer non-local potentials because of their more rapid convergence with basis set size. These non-local potentials are typically defined in momentum space and are often based on effective field theory. Comparisons of the results of the two types of methods are complicated by the use of different potentials. This thesis discusses progress made in using such non-local potentials in quantum Monte Carlo calculations of light nuclei. In particular, it shows methods for evaluating the real-space, imaginary-time propagators needed to perform quantum Monte Carlo calculations using non-local potentials and universality properties of these propagators, how to formulate a good trial wave function for non-local potentials, and how to perform a "one-step" Green's function Monte Carlo calculation for non-local potentials.
ContributorsLynn, Joel E (Author) / Schmidt, Kevin E (Thesis advisor) / Alarcon, Ricardo (Committee member) / Lebed, Richard (Committee member) / Shovkovy, Igor (Committee member) / Shumway, John (Committee member) / Arizona State University (Publisher)
Created2013
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Description
In this thesis, we present the study of several physical properties of relativistic mat- ters under extreme conditions. We start by deriving the rate of the nonleptonic weak processes and the bulk viscosity in several spin-one color superconducting phases of quark matter. We also calculate the bulk viscosity in the

In this thesis, we present the study of several physical properties of relativistic mat- ters under extreme conditions. We start by deriving the rate of the nonleptonic weak processes and the bulk viscosity in several spin-one color superconducting phases of quark matter. We also calculate the bulk viscosity in the nonlinear and anharmonic regime in the normal phase of strange quark matter. We point out several qualitative effects due to the anharmonicity, although quantitatively they appear to be relatively small. In the corresponding study, we take into account the interplay between the non- leptonic and semileptonic weak processes. The results can be important in order to relate accessible observables of compact stars to their internal composition. We also use quantum field theoretical methods to study the transport properties in monolayer graphene in a strong magnetic field. The corresponding quasi-relativistic system re- veals an anomalous quantum Hall effect, whose features are directly connected with the spontaneous flavor symmetry breaking. We study the microscopic origin of Fara- day rotation and magneto-optical transmission in graphene and show that their main features are in agreement with the experimental data.
ContributorsWang, Xinyang, Ph.D (Author) / Shovkovy, Igor (Thesis advisor) / Belitsky, Andrei (Committee member) / Easson, Damien (Committee member) / Peng, Xihong (Committee member) / Vachaspati, Tanmay (Committee member) / Arizona State University (Publisher)
Created2013
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Description
For this project, the diffuse supernova neutrino background (DSNB) has been calculated based on the recent direct supernova rate measurements and neutrino spectrum from SN1987A. The estimated diffuse electron antineutrino flux is ∼ 0.10 – 0.59 /cm2/s at 99% confidence level, which is 5 times lower than the Super-Kamiokande 2012

For this project, the diffuse supernova neutrino background (DSNB) has been calculated based on the recent direct supernova rate measurements and neutrino spectrum from SN1987A. The estimated diffuse electron antineutrino flux is ∼ 0.10 – 0.59 /cm2/s at 99% confidence level, which is 5 times lower than the Super-Kamiokande 2012 upper limit of 3.0 /cm2/s, above energy threshold of 17.3 MeV. With a Megaton scale water detector, 40 events could be detected above the threshold per year. In addition, the detectability of neutrino bursts from direct black hole forming collapses (failed supernovae) at Megaton detectors is calculated. These neutrino bursts are energetic and with short time duration, ∼ 1s. They could be identified by the time coincidence of N ≥2 or N ≥3 events within 1s time window from nearby (4 – 5 Mpc) failed supernovae. The detection rate of these neutrino bursts could get up to one per decade. This is a realistic way to detect a failed supernova and gives a promising method for studying the physics of direct black hole formation mechanism. Finally, the absorption of ultra high energy (UHE) neutrinos by the cosmic neutrino background, with full inclusion of the effect of the thermal distribution of the background on the resonant annihilation channel, is discussed. Results are applied to serval models of UHE neutrino sources. Suppression effects are strong for sources that extend beyond z ∼ 10. This provides a fascinating probe of the physics of the relic neutrino background in the unexplored redshift interval z ∼ 10 – 100. Ultimately this research will examine the detectability of DSNB, neutrino bursts from failed supernovae and absorption effects in the neutrino spectrum.
ContributorsYang, Lili, 1970- (Author) / Lunardini, Cecilia (Thesis advisor) / Alarcon, Ricardo (Committee member) / Shovkovy, Igor (Committee member) / Timmes, Francis (Committee member) / Vachaspati, Tanmay (Committee member) / Arizona State University (Publisher)
Created2013
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Description
In this thesis a new method based on the Tight-Binding Linear Muffin Tin Orbital (TB-LMTO) formalism and the Quasiparticle Self-consistent GW (QSGW) approximation is proposed. The method is capable of generating accurate electronic bands structure of large supercells necessary to model alloys structures. The strategy consist in building simple and

In this thesis a new method based on the Tight-Binding Linear Muffin Tin Orbital (TB-LMTO) formalism and the Quasiparticle Self-consistent GW (QSGW) approximation is proposed. The method is capable of generating accurate electronic bands structure of large supercells necessary to model alloys structures. The strategy consist in building simple and small hamiltonian from linear Muffin-tin-orbitals (LMTO). Parameters in this hamiltonian are then used to fit the difference in QSGW self-energies and LDA exchange-correlation potentials. The parameter are assumed to transfer to new environments --- a procedure we check carefully by comparing our predicted band to QSGW bands for small supercells. The method possess both the accuracy of the QSGW approximation, (which is the most reliable way to determine energy bands accurately, and yet too expensive for the large supercells required here), and the efficiency of the TB-LMTO method. The accurate and highly efficient hamiltonian is used to predict the electronic and optical transitions of Si1-xGex alloys and SnxSiyGe1-x-y alloys. The goal is to engineer direct band gap material compatible with the silicon technology. The results obtained are compared to available experimental data.
ContributorsDonfack, Hermann Azemtsa (Author) / Van Schilfgaarde, Mark (Thesis advisor) / Dow, John D. (Thesis advisor) / Ponce, Fernando (Committee member) / Ritchie, Barry (Committee member) / Chamberlin, Ralph (Committee member) / Arizona State University (Publisher)
Created2011
ContributorsCoffey, Brennan (Performer) / Novak, Gail (Pianist) (Performer) / ASU Library. Music Library (Publisher)
Created2021-04-26
ContributorsHolly, Sean (Performer) / Wright, Aaron (Performer) / Novak, Gail (Pianist) (Performer) / ASU Library. Music Library (Publisher)
Created2021-04-29