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Stafford, Samuel JA Search for Ultra-high Energy Cosmic Neutrinos: Data Analysis of the Antarctic Impulsive Transient Antenna, Third Flight
Doctor of Philosophy, The Ohio State University, 2017, Physics
Ultra-high Energy (UHE) neutrinos represent an increasingly important messenger in astronomy and astrophysics. The Antarctic Impulsive Transient Antenna (ANITA) experiment campaign utilizes a balloon-borne phased antenna array to detect coherent Cherenkov radio-frequency pulses induced by UHE neutrinos interacting with the Antarctic ice. We analyzed the data from the third ANITA flight (ANITA-III) for evidence of Ultra-high energy neutrinos by augmenting interferometric methods used in analyses of previous ANITA flights. Continuous wave (CW) radio content from ground-based Antarctic habitations and orbiting geostationary communications satellites interferes with the detection and analysis of neutrino-induced radio signals; we developed circular polarization analysis methods to facilitate improved rejection of false positives induced by satellite CW. We also developed new methods of calculating signal-to-noise ratio (SNR) of event waveforms, and enhanced event localization by applying a probability distribution function (PDF) based on the measured resolution of our interferometry. We developed a final linear discriminant cut for rejecting thermal and anthropogenic signals by dividing the continent into equal-area bins and optimizing the cut to each individual bin, so as to obtain the strongest possible the upper limit on cosmic neutrino flux.

Committee:

James Beatty, PhD (Advisor); John Beacom, PhD (Committee Member); Amy Connolly, PhD (Committee Member); Richard Kass, PhD (Committee Member)

Subjects:

Astrophysics; Physics

Keywords:

neutrinos; interferometry; radio; antarctica; ANITA; antarctic impulsive transient antenna; ultra high energy neutrinos; astroparticle physics; askaryan;

Timko, MarkSearch for neutrino oscillations at LAMPF /
Doctor of Philosophy, The Ohio State University, 1987, Graduate School

Committee:

Not Provided (Other)

Subjects:

Physics

Keywords:

Neutrinos;Oscillations

Hoftun, Jan SigvePrompt production of muon neutrinos and muon antineutrinos in proton-tungsten collisions /
Doctor of Philosophy, The Ohio State University, 1983, Graduate School

Committee:

Not Provided (Other)

Subjects:

Physics

Keywords:

Neutrinos;Muons;Antineutrinos;Protons;Tungsten

Corwin, Luke AndrewLeptonic Decays of the Charged B Meson
Doctor of Philosophy, The Ohio State University, 2008, Physics
We present a search for the decay of the charged B meson into a charged lepton and a neutrino 458.9 million Upsilon(4S) decays recorded with the Babar detector at the SLAC PEP-II B-Factory. A sample of events with one reconstructed exclusive semileptonic B decay is selected, and in the recoil a search for the signal decay is performed. The tau lepton is identified in decays to an electron and two neutrinos; a muon and two neutrinos; a charged pion and a neutrino; or a charged pion, a neutral pion, and a neutrino. The analysis strategy and the statistical procedure is set up for branching fraction extraction or upper limit determination. We determine from the data set a preliminary measurement of the branching fraction a charged B decaying to a tau lepton and a neutrino = (1.8 ± 0.8 ± 0.1)E-4, which excludes zero at 2.4 standard deviations. We extract the B meson decay constant = 255 ± 58 MeV. Combination with the hadronically tagged measurement yields (1.8 ± 0.6)E-4. We also set preliminary limits on the branching fraction of charged B decaying to an electron and a neutrino at 7.7E-6 and the charged B decaying to a muon and a neutrino at 11E-6. The limits are at the 90% confidence level.

Committee:

Klaus Honscheid, PhD (Advisor); Eric Braaten, PhD (Committee Member); Richard Kass, PhD (Committee Member); Mike Lisa, PhD (Committee Member); Hayrani Oz, PhD (Committee Member)

Subjects:

Physics

Keywords:

leptonic; charged B decays; meson; neutrinos; babar; semileptonic tags;

Volk, James ThomasThe prompt electron neutrino to muon neutrino ratio from 400 GeV protons on tungsten /
Doctor of Philosophy, The Ohio State University, 1983, Graduate School

Committee:

Not Provided (Other)

Subjects:

Physics

Keywords:

Quarks;Neutrinos;Muons;Protons;Tungsten

Griffith, Nathan EMicrowave Detection of Cosmic Rays and Multi-Messenger Analysis of the Parameters of Ultra-High Energy Astrophysical Sources
Doctor of Philosophy, The Ohio State University, 2015, Physics
The study of ultra-high energy (UHE) cosmic particles is frequently characterized by its low statistics, and a central problem of the field is to find novel ways to navigate this challenge. The research presented in this dissertation attempts to address this problem in two ways: first, by investigating microwave radiation as a new method of UHE cosmic ray detection, and second, by using a multi-messenger (proton and neutrino) analysis to determine what current and next generation UHE neutrino detectors may be able to reveal about UHE astrophysical sources. The cosmic ray detector (called AMBER) is primarily a joint collaboration between Ohio State and the University of Hawaii. In May/June 2011 the AMBER experiment was installed at the Pierre Auger Observatory in Malargue, Argentina, and began taking data in coincidence with the observatory’s surface detector array. This work presents a description of the experiment, a calibration based on an astrophysical radio source (the Milky Way galaxy), and an analysis of data. The second half of this document describes a multi-messenger analysis performed with co-authors Amy Connolly and Shunsaku Horiuchi on a publication in preparation. Fits to Pierre Auger 2013 data are used in conjunction with a spectral model and simulations of UHE neutrino detectors to explore the UHE source parameters of cosmic evolution and source spectrum cutoff. Constraints provided using the effective areas of the ANITA 3, ARA, and EVA detectors are considered.

Committee:

James Beatty (Advisor); John Beacom (Committee Member); Robert Perry (Committee Member); Brian Winer (Committee Member)

Subjects:

Astrophysics; Physics

Keywords:

physics; high energy; cosmic rays; experiment; detector; microwave; neutrinos; astrophysics

Strigari, Louis EExploring the universe with neutrinos
Doctor of Philosophy, The Ohio State University, 2005, Physics
I begin by reviewing the standard model of cosmology and neutrino physics. I then embark on the study of the Diffuse Supernova Neutrino Background (DSNB). I will initially focus on how the DSNB flux can be measured at the currently operating KamLAND and Super-Kamiokande (Super-K) detectors. This study is motivated by the recent reduction of atmospheric backgrounds at Super-K, and improved observational results for the star formation history, e.g., from the Sloan Digital Sky Survey (SDSS). The best estimate for the flux at Super-K is slightly below, but very close to the current Super-K experimental upper limit. In fact, I will show that the Super-K upper limit is already inconsistent with a range of star formation histories allowed by the SDSS data. I then estimate that the DSNB should be detected at Super-K with a total of about 9 years of data. Although the KamLAND detector is a much smaller compared to Super-K, it profits from being practically background-free and from its sensitivity to the lower energy supernova neutrinos. I show that KamLAND could make a 1 sigma detection of the DSNB with a total of about 5 years of data. Given the small expected DSNB event rate, I will also consider the detection of the DSNB in a modified Super-K detector with a lower threshold and reduced background where the time to detection can be reduced by a factor of ten relative to the existing Super-K estimate.

Committee:

Terry Walker (Advisor)

Subjects:

Physics, Astronomy and Astrophysics

Keywords:

NEUTRINOS; DSNB; Supernova; Redshift; flux; UNIVERSE; Neutrino Masses

Ng, Chun YuSeeking the Light in the Dark: Quests for Identifying Dark Matter
Doctor of Philosophy, The Ohio State University, 2016, Physics
The night sky is a beautiful display of stars and galaxies. We have come a long way to realize that they are made with substances that can be produced and studied on Earth. However, it has been discovered that those substances make up only 5% of the observable Universe, with the remaining 95% being mysterious substances called dark matter and dark energy, both of which have never been observed directly. Their nature is among the most profound questions in modern science, and unquestionably holds the key to the fundamentals of the Universe and laws of physics. In this dissertation, I discuss a series of papers related to studies of dark matter. I revisit the problem of dark matter annihilation in the extragalactic background radiation, and show that they are sensitive to the properties of the smallest dark matter halos. I show that the newly discovered high-energy astrophysical neutrinos can be used to test secret neutrino interactions through their propagation in the Cosmic Neutrino Background. I discuss how we use the Fermi-GBM to search for sterile neutrino dark matter in a region of parameter space that is not probed otherwise. I discuss a novel method for testing dark matter annihilation/decay signals with a line spectrum. Lastly, I discuss new and interesting results from gamma-ray observations of the Sun, and how this is related to future dark matter searches from the Sun.

Committee:

John Beacom, Professor (Advisor); Amy Connolly, Professor (Committee Member); Robert Perry, Professor (Committee Member); Todd Thompson, Professor (Committee Member)

Subjects:

Astronomy; Astrophysics; Physics

Keywords:

Dark matter, neutrinos, gamma rays, cosmic rays, astrophysics, particle physics, physics

Laha, RanjanUsing the dark to see: dark matter and neutrinos enlighten the Universe
Doctor of Philosophy, The Ohio State University, 2014, Physics
We discuss two important research avenues in astroparticle physics: dark matter and neutrinos. We discuss both direct and indirect detection of dark matter. We calculate the signatures of dark matter annihilation from galaxy clusters in neutri- nos. We show the constraints on dark matter annihilation from radio measurements near the Galactic Center. We consider the dark matter annihilation contribution to the isotropic diffuse gamma-ray background and show how to determine the mini- mum dark matter halo mass for a given dark matter mass and annihilation channel. Motivated by recent hints on dark matter self-interactions, we calculate the nuclear recoil spectrum from a bound state dark matter scattering with a nuclei at rest in a dark matter direct detection experiment. We discuss non-standard interactions of neutrinos and astrophysical neutrino detection in the second part of the thesis. We derive strong constraints on a light Abelian gauge boson coupling to Standard Model leptons. In light of the recent detection of high energy neutrinos in IceCube, we discuss the cascade detection of high energy astrophysical neutrinos in IceCube and point out the benefits of this detection channel. We propose a new method to detect supernova electron neutrino in gadolinium loaded Super-Kamiokande detector and show that it can be used to measure the supernova electron neutrino spectrum to ~ 20% accuracy.

Committee:

John Beacom (Advisor)

Subjects:

Physics

Keywords:

Dark matter, Neutrinos

Gauthier, AlainCharmed-particle lifetime measurements and limits for neutrino oscillations and the existence of the tau neutrino /
Doctor of Philosophy, The Ohio State University, 1987, Graduate School

Committee:

Not Provided (Other)

Subjects:

Physics

Keywords:

Particles;Neutrinos

Krofcheck, DavidGamow-Teller strength distributions for solar neutrino detectors via the (p,n) reaction /
Doctor of Philosophy, The Ohio State University, 1987, Graduate School

Committee:

Not Provided (Other)

Subjects:

Physics

Keywords:

Solar neutrinos;Detectors

Crisler, Michael Bruce,Prompt neutrino production in a beam dump experiment/
Doctor of Philosophy, The Ohio State University, 1983, Graduate School

Committee:

Not Provided (Other)

Subjects:

Physics

Keywords:

Quarks;Neutrinos

Dailey, Brian TAnalysis of the second flight of the ANtarctic Impulsive Transient Antenna with a focus on filtering techniques
Doctor of Philosophy, The Ohio State University, 2017, Physics
The observed cutoff in the cosmic ray spectrum leads to a highly motivated expectation of an ultra-high energy (UHE) neutrino flux, coming from interactions between the cosmic rays and cosmic microwave background photons. Although no UHE neutrinos have yet been detected; better background separation and removal will help accelerate the search. Past flights of the ANtarctic Impulsive Transient Antenna (ANITA) experiment have set the strongest limits on the UHE neutrino flux above 10^{19} eV. Due to the advanced sensitivity of future flights to both signal and anthropogenic backgrounds, the techniques used in the past analyses may not be sufficient to remove backgrounds. Here, we discuss processes developed for this analysis. First, we discuss newly techniques to filter event waveforms in both the amplitude and phase spectra. These new techniques were applied to the ANITA-2 experiment data set. We discuss a new technique developed that uses equal area bins of ice on the Antarctic continent. Further, we define a set of analysis cuts, how the analysis cuts were optimized for maximum sensitivity for UHE neutrinos, how the number of background and neutrino events were estimated. For our search, we used the maximal Kotera et. al. 2010 flux model and optimized based on this model. After optimization, we found zero events from the 10% sample passing all cuts. These techniques will prove useful for future flights of ANITA as the sensitivity of the instrument increases. The optimization procedure can also provide a starting point for future analysis. The filtering technique shown here decreased mis-reconstruction in pointing of events. The HealPix method, while requiring further refinement, shows promise by retaining valuable areas of ice that may have been removed from previous analyses.

Committee:

Amy Connolly (Advisor); John Beacom (Committee Member); Klaus Honscheid (Committee Member); Andrew Heckler (Committee Member)

Subjects:

Physics

Keywords:

ANITA; Ultra High Energy Neutrinos; HealPix; ANITA-2 analysis; amplitude filtering; phase filtering;