Дисертації: "High energy neutrino conversion"

1

Lunardini, Cecilia. "Matter Effects on Conversion of Neutrinos from Supernovae and Cosmological Sources." Doctoral thesis, SISSA, 2001. http://hdl.handle.net/20.500.11767/4324.

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This thesis collects in a unitary presentation the results of a series of papers [25, 54, 55, 56] in which we studied the effects of matter on oscillations of cosmic neutrinos from various sources. After a first introductory chapter, in chapter 2 we consider the conditions for significant matter effect; in particular we show that a minimum width of medium is required, independently of the neutrino oscillation parameters and energy, and of the matter density profile. In chapter 3 this condition is applied to high-energy neutrinos propagating across the universe: -vve find that substantial effect is produced by the relic neutrino background provided that it has a large CF-asymmetry and the neutrino source is at cosmological distance. The effect and its observability are discussed in detail. The chapters 4-6 are devoted to supernova neutrinos and their regeneration in the matter of the Earth. A detailed description of the Earth matter effect is presented in chapter 4, and in chapter 5 we give an application to the neutrino signal from SN1987 A. vVe find that the Earth effect could reconcile the difference in the energy spectra of the Kamiokande and IMB data. In chapter 6 we consider future supernova neutrino detections: we show that the Earth matter effect is observable and has important implications on the reconstruction of the neutrino mixing scheme and mass spectrum. The discussion is completed by three appendices.

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2

Nielsen, Adam Derek. "Monte Carlo calculation of fluence-to-ambient dose equivalent conversion coefficients for high-energy neutrons." Thesis, Georgia Institute of Technology, 1998. http://hdl.handle.net/1853/16424.

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3

Allport, P. P. "High energy neutrino scattering at low Q'2." Thesis, University of Oxford, 1986. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.376865.

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4

Guillaud, Mathilde. "Neutrino oscillations at very high energy/matter density." Thesis, KTH, Fysik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-292510.

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Neutrino oscillations in matter can be studied in different regimes, depending on the energy of the incoming neutrinos and the matter density of the medium. In this thesis we investigate neutrino oscillations in dense matter at very high energy (TeV-PeV range), taking into account the absorption that the neutrinos may undergo in such dense media. This absorption phenomenon is relevant for neutrino telescope measurements of astrophysical neutrinos. We begin with a brief reminder on neutrino oscillations in vacuum and the construction of the PMNS matrix. Then, we proceed with calculations for dense matter. We then explore the accuracy of the resulting effective 2-neutrino mixing formulas. They present a good accuracy for Earth-like densities in our range of energies. We develop the calculations for oscillation probabilities in dense matter with absorption through charged-current inelastic scattering for both the two-neutrino and three-neutrino case. We find that in dense media, astrophysical neutrinos indeed undergoabsorption, which reduces signicantly the fluxes for each flavor, with a resonant absorption of electron-anti-neutrinos around E_{res}\simeq 6.3PeV. We discuss the impact of neutrino absorption in the Earth for neutrino telescopes measurements. We find that solar and lunar shadowing is not problematic for current telescopes but could be a good angular resolution indicator for new telescopes to come.
Neutrinooscillationer i materia kan studeras i olika regimer beroende på inkommande neutrinernas energi och densiteten hos det bakomliggande mediet. I detta examensarbete undersöker vi neutrinooscillationer i gränsen av tät materia och mycket hög energi (TeV-PeV-intervall), och tar hänsyn till den absorption av neutriner som då kan inträffa i sådant materia. Detta absorptionsfenomen är relevant för neutrino-teleskopmätningar av astrofysiska neutriner. Vi börjar med att kort påminna oss om neutrinooscillationer i vakuum och konstruktionen av PMNS-matrisen. Vi försätter sedan med beräkningar av neutrinooscillationer i tät materia. Vi undersöker noggrannheten i resulterande effektiva 2-neutrino-blandningsformlerna. De uppvisar en god noggrannhet i jordlika materieprofiler i vårt intervall av energier. Vi utvecklar beräkningarna av oscillationssannolikheterna i tät materia inklusive absorption genom laddad ström oelastisk spridning i båda två- och tresmaksfallen. Vi finner att astrofysiska neutriner i tät materia absorberas, vilket minskar betydligt flödena för varje smak, med en resonansabsorption av elektron-antineutrino omkring E_res\simeq 6.3PeV. Vi diskuterar sedan effekterna av neutrinoabsorption på jorden för neutrino-teleskopmätningar. Vi finner att sol- och månskuggning är inte problematisk för nuvarande teleskop och kunde vara en bra vinkelupplösningsindikator för kommande teeskop.

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5

Li, Xiaoyue. "A Joint Analysis of T2K Beam Neutrino and Super-Kamiokande Sub-GeV Atmospheric Neutrino Data." Thesis, State University of New York at Stony Brook, 2018. http://pqdtopen.proquest.com/#viewpdf?dispub=10844911.

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Neutrino oscillation is a phenomenon in which neutrinos produced from charged current weak interactions can change flavor as they propagate. The mixing between the three flavor eigenstates and mass eigenstates can be measured through neutrino oscillations as the oscillation probabilities depend on the mixing angles and neutrino mass squared differences.

T2K is a long baseline neutrino experiment, in which a nearly pure muon neutrino or muon antineutrino beam is produced at J-PARC on the east coast of Japan and travels 295 km through the Earth’s crust towards the far detector, Super-Kamiokande (Super-K), a 50 kiloton water Cherenkov detector, in the west of Japan. The neutrino fluxes in the absence of oscillation are measured by the near detectors 280 meters away from the target, and again with oscillation effects at Super-K. Aside from the beam neutrino from J-PARC, Super-K also measures neutrino oscillations independently through the neutrinos produced in the Earth's atmosphere.

This thesis presents the first analysis in which both the T2K beam neutrino data and the sub-GeV atmospheric neutrino data at Super-K are used in a unified framework to measure neutrino oscillation parameters. The beam neutrino samples are selected for optimal sensitivity to sin²&thetas;₂₃ and δ_CP. A Bayesian analysis using a Markov Chain Monte Carlo method is performed. Using T2K Runs 1–8 data which amounts to 14.7 × 10₂₀ protons on target (POT) in neutrino-mode and 7.6 × 10₂₀ POT in antineutrino-mode, and 2520 days of Super-K data, the oscillation parameters are measured to be sin²&thetas;₂₃ = 0.528^+0.032_–0.028, |Δ m²₃₂| = 2.46^+0.084_–0.060(10^–3eV²), sin²&thetas;₁₃ = 0.0270^+0.0065_–0.0047; and the 90% credible interval of δ_CP is [–π, –0.18]&[2.33, π]. When the data is also combined with the constraint on sin² 2&thetas;₁₃ = 0.0857 ± 0.046 from reactor neutrino experiments, the oscillation parameters are measured to be sin²&thetas;₂₃ = 0.543^+0.026_–0.023, |Δm² 32| = 2.49^+0.042_–0.090(10^–3eV²), sin²&thetas;₁₃ = 0.0223^+0.0012_–0.0013; the 90% credible interval of δ_CP is [–π, –0.628], and the CP-conserving value δ_CP = 0 is excluded at 2σ.

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6

Michaud, Denis 1970. "Neutrino propagation through matter." Thesis, McGill University, 1994. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=55513.

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In this thesis, we examine the evolution of a quantum system through background matter in order to determine the conditions of validity required for a description in terms of an effective Hamiltonian. General scattering rate equations are obtained for coherent diffuse scattering. We find, as expected, that the diffuse scattering rate is small compared to the coherent scattering rate in a medium with low fluctuations allowing an effective Hamiltonian description. However, for a more turbulent background, it is still possible to have more significant contributions to the diffuse scattering which may affect the existing theory of neutrino flavor conversion (MSW effect).

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7

Gamsizkan, Halil. "A Qcd Analysis Of High Energy Neutrino-nucleon Interactions." Master's thesis, METU, 2003. http://etd.lib.metu.edu.tr/upload/1006428/index.pdf.

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In this thesis, a leading-order QCD analysis of structure functions in neutrinonucleon interactions is performed. From the CCFR nucleon structure function data, the QCD parameter Lambda has been extracted. This measurement also corresponds to a measurement of the strong coupling constant. Two fits to the data have been performed, the nonsinglet-only fit and the singlet-nonsinglet combined fit. The result for Lambda was found to be 289 +62 ¡
59 §
76 MeV, where the errors are statistical and systematical, respectively. This result is compared to the world-wide measurements of this quantity. In order to verify the agreement, also the logarithmic slopes of the QCD model and the structure function data are calculated and compared.

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8

Olivo, Martino. "Neutrino emission from high-energy component gamma-ray bursts." Licentiate thesis, Uppsala universitet, Högenergifysik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-132961.

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Gamma-ray bursts (GRBs) are brief and sudden explosions radiating most of their energy in the soft γ-ray band ( 100 keV). In the context of multimessenger astroparticle physics recent observations of GRBs provide an excellent benchmark for testing theoretical models of high energy emission mechanisms. Acceleration of hadrons in the engine is expected to produce high energy neutrinos and gamma-rays simultaneously via π±/π0 decays, thus reinforcing the motivation for coincident searches in km3 neutrino telescopes. The Waxman-Bachall spectra and the corresponding expected neutrino rates in IceCube are derived here for GRB090510 amd GRB090902B recently detected by the Fermi Large Area Telescope. The implications of the significant detection of deviations from the Band function fit in photon spectra and a model that explains these extra-components in terms of π0-decay photons are presented here and the relevance to neutrino astronomy is shown.

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9

Hill, Gary Colin. "Experimental and theoretical aspects of high energy neutrino astrophysics /." Title page, table of contents and summary only, 1996. http://web4.library.adelaide.edu.au/thesis/09PH/09phh6461.pdf.

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10

O'Rourke, Brogan Roisín. "AGN Candidates for High Energy Neutrino Emission in IceCube." Thesis, Uppsala universitet, Högenergifysik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-409739.

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Since the construction of the IceCube Neutrino Observatory was completed in 2010, many amazing discoveries have been made in the field of neutrino physics. Recently a neutrino event has been linked to an blazar-type active galactic nucleus source, bringing us one step closer to understanding the production of high-energy extragalactic neutrinos and ushering in a new era of multimessenger astronomy. This was found by linking the neutrino event to one of the Fermi Collaboration’s gamma ray sources which had a blazar counterpart. The quest to link other neutrino events to AGN (active galactic nuclei) sources through collaboration with the Fermi Large Area Telescope has turned up some interesting candidates. The fact that some of these potential sources are not blazars is curious and, although unconfirmed as neutrino sources, these objects merit further investigation due to their unusual nature.

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11

CASSINA, LORENZO. "Detectors and equipment for Neutrino and High Energy Physics." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2017. http://hdl.handle.net/10281/158123.

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During my PhD I have been involved in two experiments, LHCb (at CERN) and CUORE (at LNGS). The former is devoted to search of physics beyond the Standard Model. I collaborated to characterize MaPMTs and develop the read-out electronic system. Such equipment will be used for the upgrade of the RICH detector, responsible for the particle identification. CUORE is an experiment searching the neutrinoless double beta decay in tellurium 130. I collaborated to develop and mount the electronic apparatus. The studies on the linear power supply, the slow control communication system and the ultra-precise and ultra-stable pulser board for the bolometer response stabilization, will be described.
During my PhD I have been involved in two experiments, LHCb (at CERN) and CUORE (at LNGS). The former is devoted to search of physics beyond the Standard Model. I collaborated to characterize MaPMTs and develop the read-out electronic system. Such equipment will be used for the upgrade of the RICH detector, responsible for the particle identification. CUORE is an experiment searching the neutrinoless double beta decay in tellurium 130. I collaborated to develop and mount the electronic apparatus. The studies on the linear power supply, the slow control communication system and the ultra-precise and ultra-stable pulser board for the bolometer response stabilization, will be described.

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12

Armstrong, Robert E. "Muon neutrino disappearance at MINOS." [Bloomington, Ind.] : Indiana University, 2009. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3380059.

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Thesis (Ph.D.)--Indiana University, Dept. of Physics, 2009.
Title from PDF t.p. (viewed on Jul 19, 2010). Source: Dissertation Abstracts International, Volume: 70-12, Section: B, page: 7630. Adviser: Jon Urheim.

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13

Reid, Janice. "Design and feasibility studies for a high energy neutrino detector /." Title page, abstract and contents only, 1995. http://web4.library.adelaide.edu.au/theses/09PH/09phr356.pdf.

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14

CARNITI, PAOLO. "Electronic Instrumentations for High Energy Particle Physics and Neutrino Physics." Doctoral thesis, Università degli Studi di Milano-Bicocca, 2018. http://hdl.handle.net/10281/198964.

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La presente dissertazione descrive il design, la caratterizzazione e il funzionamento di sistemi elettronici per esperimenti di Fisica delle particelle (LHCb) e Fisica del neutrino (CUORE e CUPID). A partire dal 2019, l'esperimento LHCb presso l'acceleratore LHC sarà aggiornato per lavorare a luminosità più elevata e molti dei suoi rivelatori dovranno essere riprogettati. Il rivelatore RICH, in particolare, dovrà adottare un sistema optoelettronico totalmente nuovo. Lo sviluppo di questo sistema ha già raggiunto una fase avanzata e diversi test eseguiti su fascio hanno permesso di verificare le prestazioni dell'intero sistema. Per migliorare la stabilità, il filtraggio e la regolazione delle tensioni di alimentazione del circuito di front-end, è stato sviluppato un regolatore lineare a basso dropout e resistente alla radiazione, denominato ALDO. Sono qui presentate le strategie di progetto, la misurazione delle prestazioni e i risultati delle campagne di irraggiamento di questo dispositivo. Nel campo della fisica del neutrino, grandi array di macrobolometri, come quelli adottati dall'esperimento CUORE e dal suo futuro aggiornamento CUPID, offrono delle caratteristiche uniche per lo studio del doppio decadimento beta senza neutrini. Il loro funzionamento richiede particolari strategie progettuali nel sistema elettronico di lettura, che è qui descritto nella sua interezza. Sono anche presentate nel dettaglio le misure di qualifica e ottimizzazione dei parametri di funzionamento di tutto il sistema, oltre che l'integrazione all'interno dell'area sperimentale. Infine sono presentati gli aggiornamenti di alcuni sottosistemi elettronici in vista della fase finale di CUPID.
The present dissertation describes design, qualification and operation of several electronic instrumentations for High Energy Particle Physics experiments (LHCb) and Neutrino Physics experiments (CUORE and CUPID). Starting from 2019, the LHCb experiment at the LHC accelerator will be upgraded to operate at higher luminosity and several of its detectors will be redesigned. The RICH detector will require a completely new optoelectronic readout system. The development of such system has already reached an advanced phase, and several tests at particle beam facilities allowed to qualify the performance of the entire system. In order to achieve a higher stability and a better power supply regulation for the front-end chip, a rad-hard low dropout linear regulator, named ALDO, has been developed. Design strategies, performance tests and results from the irradiation campaign are presented. In the Neutrino Physics field, large-scale bolometric detectors, like those adopted by CUORE and its future upgrade CUPID, offer unique opportunities for the study of neutrinoless double beta decay. Their operation requires particular strategies in the readout instrumentation, which is described here in its entirety. The qualification and optimization of the working parameters as well as the integration of the system in the experimental area are also thoroughly discussed, together with the latest upgrades of two electronic subsystems for the future CUPID experiment.

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15

Li, Junyue. "Perovskite thermoelectric materials for high-temperature energy conversion." Thesis, Boston University, 2014. https://hdl.handle.net/2144/21206.

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Thesis (M.Sc.Eng.)
Despite of recent success in achieving the figure of merit ZT > 1 based on the nanoscale patterned thermoelectric structures, there have been few stable n-type materials with attractive thermoelectric responses for high temperature applications at T > 800K. In this thesis, we applied the first-principles density functional theory (DFT) calculations to probe the structure and thermoelectric properties relationship of a comprehensive series of perovskite materials. The density of states (DOS), Seebeck coefficient S, electric conductivity σ, and electronic contribution of the thermal conductivity Ke were obtained directly from the first-principles DFT calculations. In particular, Lanthanum (La), Gadolinium (Gd), Samarium (Sm), Yttrium (Y) doped MU+2093SrU+2081U+208BU+2093TiOU+2083 and Niobium (Nb) doped SrNbyTi1-yOU+2083 and doubly doped LaU+2093SrU+2081U+208BU+2093NbyTi1-yOU+2083 systems were studied. The change of the power factor S^2σ corresponding to the different dopant concentration had a good agreement with the experimental data. Our computed power factors S^2σ as a function of the dopant con- centration agree well with the available experimental data, and at the same time provide new insights for the optimal compositions. In the low doping region (x U+003E 12:5%), gadolinium and niobium are the best candidates of perovskite thermoelectric materials while at high doping level (x U+003E 25%), lanthanum and yttrium are the best options. In the case of doubly doped perovskites LaU+2093SrU+2081U+208BU+2093NbyTi1-yOU+2083, our calculations predict that the x= 12.5% and y= 12.5% is the best choice.

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16

Elieff, Stefan H. P. "Determining properties of neutralino dark matter using high-energy neutrino events." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1998. http://www.collectionscanada.ca/obj/s4/f2/dsk2/tape15/PQDD_0014/MQ33841.pdf.

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17

Böser, Sebastian. "Acoustic detection of ultra-high energy cascades in ice." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2007. http://dx.doi.org/10.18452/15670.

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Existierende Neutrinoteleskope sind für den Nachweis von Neutrinos aus astrophysikalischen Quellen mit Energien im TeV Bereich optimiert. Aufgrund der geringen Flüsse und Wirkungsquerschnitte wurden bislang keine extraterrestrischen hochenergetischen Neutrinos beobachtet. Erst die im Bau befindlichen kubikkilometer-großen Cherenkov-Neutrinodetektoren werden das notwendige Volumen haben, um diese nachzuweisen. Für Neutrinos aus Wechselwirkungen der kosmischen Strahlung im EeV-Bereich mit dem kosmischen Mikrowellenhintergrund wird dennoch nicht mehr als ein Ereignis im Jahr erwartet. Nachweisvolumen in der Größenordnung von 100 km^3 sind notwendig, um den Fluß dieser Neutrinos zu bestimmen und die vorhergesagten Wirkungsquerschnitte zu überprüfen. Alternative Meßtechniken sind erforderlich, um einen Detektor dieses Ausmaßes zu realisieren. Eine vielversprechende Idee ist die Erfassung akustischer Wellen aus den in der Neutrinowechselwirkung erzeugten hadronischen Kaskaden. Aufgrund der höheren Signalstärke und der großen Schalldämpfungslängen ist die Eisdecke des Südpols dem Wasser der Ozeane als Medium vorzuziehen. Zunächst sind jedoch geeignete Sensoren, eine Überprüfung der thermo-akustischen Schallerzeugung und Kenntnisse der akustischen Eigenschaften des Eises von Nöten. In einer theoretischen Ableitung konnte die Äquivalenz der Mechanismen der Erzeugung akustischer Wellen durch thermo-elastische Anregung in Flüßigkeiten und isotropen Festkörpern gezeigt werden. Einer Analyse des existierenden Wissensstandes folgte die Simulation eines kombinierten Cherenkov-Radiowellen-Ultraschall-Detektors. Für den Einsatz im Eis wurden spezielle akustische Sensoren entwickelt und zur Erfassung der Schallemission von intensiven Protonen- und Laserstrahlen eingesetzt. Darauf aufbauend wurde ein akustische Sender- und Empfänger-Aufbau entwickelt, mit dem Ziel, die Ultraschalleigenschaften des südpolaren Eises in-situ zu untersuchen. Die Ergebnisse dieser ersten Bemühungen werden in dieser Arbeit vorgestellt.
Current neutrino telescopes are designed to detect neutrinos with energies in the TeV range. Due to the low fluxes and small cross sections, no high energy neutrinos of extraterrestrial origin have been observed so far. Only the Cherenkov neutrino detectors on the km^3 scale that are currently under construction will have the necessary volume to observe these rare interactions. Yet, for neutrinos from interactions of the ultra-high energy cosmic at EeV energies rays with the ambient cosmic microwave background, event rates of only one per year are expected. To measure the flux and verify the predicted cross sections of these cosmogenic neutrinos, an observed volume of around 100 km^3 will be necessary, that will not be feasible with existing detection techniques. Alternative methods are required to build a detector on these scales. One promising idea is to record the acoustic waves generated in cascades following the neutrino interaction. Higher amplitudes of the sonic signal and the large absorption length of sound favour South Polar ice instead of sea water as a medium. For an estimate of the potential of such a detector, suitable acoustic sensors, a verification of the model of thermo-acoustic sound generation and a determination of the acoustic properties of the ice are necessary. In a theoretical derivation the mechanism of thermo-elastic excitation of acoustic waves was shown to be equivalent for isotropic solids and liquids. A detailed analysis of the existing knowledge and a simulation study of a hybrid optical-radio-acoustic detector have been performed. Ultrasonic sensors dedicated to in-ice application were developed and have been used to record acoustic signals from intense proton and laser beams. Based on this, the hitherto largest array of acoustic sensors and transmitters was devised and implemented, with the aim to study the ultrasonic properties of the South Polar ice in-situ. Results from all of these first efforts are presented.

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18

Bierman, David M. (David Matthew). "Full spectrum utilization for high-efficiency solar energy conversion." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/113547.

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Thesis: Ph. D., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2017.
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 88-97).
Today, two dominant strategies for solar energy harvesting exist: solar thermal and photovoltaic. Solar thermal energy harvesting offers the distinct ability to both utilize the full solar spectrum and provide dispatchable electrical power to the grid. By contrast, the generation of power via the photovoltaic effect can reduce the complexity of a system by eliminating moving parts. Conversion strategies which use both thermal and photovoltaic principles capitalize on the advantages of each. This thesis explores the potential of these technologies through both experimental and theoretical device-level studies. First, we explored solar thermophotovoltaic devices (STPVs) which convert broadband sunlight to narrow-band thermal radiation tuned for a photovoltaic cell. We demonstrated the highest STPV efficiency to date through the suppression of 80% of sub-bandgap blackbody radiation by pairing a one-dimensional photonic-crystal selective emitter with a tandem plasma-interference optical filter. We measured a solar-to-electrical conversion rate of 6.8%, exceeding the performance of the photovoltaic cell alone. Additionally, we show experimentally that STPVs can reduce the heat generation rates in the photovoltaic cell by a factor of two for the same power density. Next, we explored the use of spectral splitting as a different strategy to use both thermal and photovoltaic technologies. A model of an ideal solar spectral-splitting converter was developed to determine the conversion efficiency limit as well as the corresponding optimum spectral bandwidth of sunlight which should illuminate the photovoltaic cell. This bandwidth was also obtained analytically through an entropy minimization scheme and matches well with our model. We show that the maximum efficiency of the system occurs when it minimizes the spectral entropy generation. Beyond solar energy harvesting, we investigated the radiation dynamics of vanadium dioxide (VO2 ), which is of interest because of the abrupt decline of emittance at the insulator-metal transition at ~340 K. Negative differential emission is exploited to demonstrate thermal runaway of this system for the first time. These results are used to validate a radiation heat transfer model which explores the limiting behavior of a VO2 material set.
by David M. Bierman.
Ph. D.

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19

Docker, Jones Mykalin Ann. "Monte Carlo Simulation of High Energy Neutrino Event Transport in Cerenkov Detectors." Digital WPI, 2020. https://digitalcommons.wpi.edu/etd-theses/1327.

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This body of work was aimed at the development of an application for simulating high energy neutrino events (up to 100 GeV) in GEANT4. While various Monte Carlo techniques for neutrino transport exist, this was motivated by current interest in expanding GEANT4’s application to neutrino physics and handling of neutrino related processes. Multiple neutrino observatories detect astrophysical neutrinos by measuring optical Cerenkov light produced from interactions; this application may be modified for a variety of experiments. The need for the generation of the computationally inexpensive model discussed in the paper arose from neutrino oscillation predictions for high energy cosmic neutrinos. A predicted flavour ratio of approximately 1:1:1 for nu_e:nu_mu:nu_tau within the IceCube array motivates work towards differentiating neutrino flavour across detected events. Simulation techniques can be implemented to provide information that may be used when designing data analysis algorithms. Tau neutrino transport simulation was explored in detail utilizing the developed application to probe properties of 100 GeV nu_tau events as a preliminary investigation into its many uses. Results from 10,000 nu-tau events showed agreement with preliminary calculations relating the time of flight to the contribution to the signal over time of the optical photons produced at the neutrino interaction and tau decay vertices.

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20

Voigt, Bernhard. "Sensitivity of the IceCube detector for ultra-high energy electron-neutrino events." Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2008. http://dx.doi.org/10.18452/15850.

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Zur Zeit wird das IceCube Neutrino-Teleskop am Südpol im Eis der Antarktis installiert, die Hälfte des Detektors ist bereits im Betrieb. Bei Fertigstellung im Jahr 2011 wird mehr als 1 km^3 Eis mit Photovervielfachern instrumentiert sein. IceCube bietet damit eine einzigartige Möglichkeit, die Quellen der kosmischen Strahlung mit Hilfe hochenergetischer Neutrinos zu finden. Im Rahmen dieser Arbeit wurde die Sensitivität des kompletten Icecube Detektors für den Nachweis eines diffusen Flusses von Elektronneutrinos bestimmt. Ziel war es, die Eigenschaften des Detektors für Energien oberhalb von einem PeV zu bestimmen. Besonderes Augenmerk wurde dabei auf die Simulation von elektromagnetischen Kaskaden gelegt, die in Neutrino-Nukleon-Wechselwirkungen auftreten. Da existierende Parametrisierungen die Unterdrückung der Wechselwirkungsquerschnitte durch den LPM-Effekt nicht beinhalten, wurde eine Simulation des Energieverlustes von elektromagnetischen Kaskaden für Energien oberhalb von 1 PeV entwickelt, die entsprechend modifizierte Wirkungsquerschnitte verwendet. Die Analyse, die in dieser Arbeit vorgestellt wird, nutzt die komplette Information des durch einen Photovervielfacher aufgezeichneten Ladungsverlaufes aus, die mit der Datennahme des IceCube Detektors zur Verfügung steht. Es werden neue Methoden entwickelt, um zwischen atmosphärischen Myonen-Hintergrund- und Signalereignissen von Kaskaden aus Neutrino-Nukleon-Wechselwirkungen zu unterscheiden. Die erreichbare Sensitivität innerhalb einer Laufzeit von einem Jahr ist 1.5*10^-8 E^-2 GeV/(cm^2 sr s) in einem Energiebereich von 16 TeV bis 13 PeV für den Nachweis von Elektronneutrinos eines diffusen Flusses. Eine Verbesserung von mindestens einer Größenordnung wird erwartet, wenn alle Neutrinofamilien in die Analyse einbezogen werden. Damit sollte eine Sensitivität erreicht werden, die auf dem gleichen Niveau einer diffusen Myonenanalyse liegt.
IceCube is a neutrino telescope currently under construction in the glacial ice at South Pole. At the moment half of the detector is installed, when completed it will instrument 1 km^3 of ice providing a unique experimental setup to detect high energy neutrinos from astrophysical sources. In this work the sensitivity of the complete IceCube detector for a diffuse electron-neutrino flux is analyzed, with a focus on energies above 1 PeV. Emphasis is put on the correct simulation of the energy deposit of electromagnetic cascades from charged-current electron-neutrino interactions. Since existing parameterizations lack the description of suppression effects at high energies, a simulation of the energy deposit of electromagnetic cascades with energies above 1 PeV is developed, including cross sections which account for the LPM suppression of bremsstrahlung and pair creation. An attempt is made to reconstruct the direction of these elongated showers. The analysis presented here makes use of the full charge waveform recorded with the data acquisition system of the IceCube detector. It introduces new methods to discriminate efficiently between the background of atmospheric muons, including muon bundles, and cascade signal events from electron-neutrino interactions. Within one year of operation of the complete detector a sensitivity of 1.5*10^-8 E^-2 GeV/(cm^2 sr s) is reached, which is valid for a diffuse electron-neutrino flux in the energy range from 16 TeV to 13 PeV. Including all neutrino flavors in this analysis, an improvement of at least one order of magnitude is expected, reaching the anticipated performance of a diffuse muon analysis.

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21

Williams, Simon Shaughan. "A cylindrical mirror analyser for neutrino mass measurement." Thesis, University of Oxford, 1989. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.253133.

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22

Niner, Evan. "Observation of electron neutrino appearance in the NuMI beam with the NOvA experiment." Thesis, Indiana University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3722542.

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NOvA is a long-baseline neutrino oscillation experiment that uses two functionally identical detectors separated by 810 kilometers at locations 14 milliradians off-axis from the NuMI muon neutrino beam at Fermilab. At these locations the beam energy peaks at 2 GeV. This baseline is the longest in the world for an accelerator-based neutrino oscillation experiment, which enhances the sensitivity to the neutrino mass ordering. The experiment studies oscillations of the muon neutrino and anti-neutrino beam that is produced. Both detectors completed commissioning in the summer of 2014 and continue to collect data. One of the primary physics goals of the experiment is the measurement of electron neutrino appearance in the muon neutrino beam which yields measurements of the oscillation parameters $\sin

{2}2\theta_{13}$, $\delta$, and the neutrino mass ordering within the standard model of neutrino oscillations. This thesis presents the analysis of data collected between February 2014 and May 2015, corresponding to $3.52\times 10

{20}$ protons-on-target. In this first analysis NOvA recorded 6 electron neutrino candidates which is a $3.3\sigma$ observation of electron neutrino appearance. The T2K experiment performs the same measurement on a baseline of 295 kilometers and has a $1~\sigma$ preference for the normal mass ordering over the inverted ordering over the phase space of the CP violating parameter $\delta$, which is also weakly seen in the NOvA result. By the summer of 2016 NOvA will triple its statistics due to increased beam power and a completed detector. If electron neutrinos continue to be observed at the current rate NOvA willl be able to establish a mass ordering preference at a similar confidence level to T2K.

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23

McCutcheon, Michael Warren. "Analysis of a 2-3 exchange symmetric neutrino mass matrix." Thesis, McGill University, 2002. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=79048.

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We present an analysis of the requirements of a 2--3 exchange symmetry in the neutrino mass matrix in comparison to the experimentally allowed ranges of neutrino oscillation parameters. The symmetric matrix, being defined at an energy scale appropriate to a right-handed neutrino in a See-saw scheme of mass suppression, is subject to evolution under Supersymmetric Renormalisation Group Equations, in order to interpret the matrix at experimental energies. By way of motivation we discuss the status of neutrino mass in the Standard Model and justify the context of the analysis by examining the mechanisms and evidence for oscillations. We then review the See-saw mechanism and also the process of renormalisation and its implications for bridging disparate energy scales. We present the relevant Renormalization Group Equations and demonstrate the parameterisation of pertinent Renormalization Group effects. Finally, we review previous work analysing this symmetry before updating some of these results and extending the analysis to its global behaviour in the space of both solar and atmospheric neutrino oscillation parameters.

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24

Iyer, Sharada Ramalingham. "A novel approach in the detection of muon neutrino to tau neutrino oscillation from extragalactic neutrinos." Diss., The University of Arizona, 2001. http://hdl.handle.net/10150/290068.

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A novel approach is proposed for studying the ν(μ) → ν(τ) oscillation and detection of extragalactic neutrinos. Active Galactic Nuclei (AGN), Gamma Ray Bursters (GRB) and Topological Defects are believed to be sources of ultrahigh energy ν(μ) and νₑ. These astrophysical sources provide a long baseline of 100Mpc, or more, for possible detection of ν(μ) → ν(τ) oscillation with mixing parameter Δm² down to 10⁻¹⁷ eV², many orders of magnitude below the current accelerator experiments. The propagation characteristics of upward going muon and tau neutrinos is studied to show that high energy tau neutrinos cascade down in energy as they propagate through the Earth, producing an enhancement of the incoming tau neutrino flux in the low energy region. By contrast, high energy muon neutrinos get attenuated as they traverse the Earth. It is observed that the relative steepness of the incoming neutrino flux spectrum and the nadir angle of the Earth are two important factors that influence the enhancement and cascade of nutau flux. This effect provides a novel way to search for tau neutrino appearance by measuring the angular dependence of tau neutrino induced upward muons; and upward hadronic and electromagnetic showers. A Monte Carlo evaluation of tau survival probability and its range shows that at energies below 10⁷ - 10⁸ GeV, depending on the material, only tau decays are important. However, at higher energies the tau energy losses are significant, hence reducing the survival probability of tau. Here, tau energy loss for energies up to 10⁹ GeV have been calculated taking into consideration the decay of tau. An understanding of tau energy loss at very high energies could help with the interpretation of long tracks produced by charged particles in large underground detectors.

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25

Aaronson, Barak D. B. "High resolution electrochemical imaging for energy conversion and storage applications." Thesis, University of Warwick, 2015. http://wrap.warwick.ac.uk/78415/.

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The work presented herein involves the development of the scanning electrochemical cell microscopy (SECCM) platform for visualizing electrochemical and (photo)electrochemical activity of processes at electrode surfaces relevant to energy applications. The use of complementary microscopy characterization techniques such as: field emission-scanning electron microscopy (FE-SEM), electron backscatter diffraction (EBSD), atomic force microscopy (AFM) and Raman microscopy provides a correlation between the localized (photo)electrochemical activity (obtained by SECCM) and physical properties of the investigated surfaces. SECCM studies of a polycrystalline platinum surface highlight the significant variations in electrochemical activity that can be measured at electrode surfaces due to variations in localized crystallographic orientation and the presence of grain boundaries. An ostensibly simple redox couple (Fe2+/3+) in two different acidic media on a polycrystalline platinum foil is utilized as a model system and the localized crystallographic orientation of the surface is determined by EBSD analysis. The approach is then extended to room temperature ionic liquids (RTILs) to study the reduction of triiodide (I3-) to iodide (I-) on polycrystalline platinum for the application of dye sensitized solar cells (DSSCs) as a counter electrode. The coupling of illumination with high sensitivity current followers and external lock-in amplifiers to the SECCM setup is described and the resulting platform is demonstrated to allow investigation of (photo)electrochemical systems. Two examples are provided: imaging photo-anodes in DSSCs and electrodeposition and characterization of conjugated polymers on a transparent electrode for organic photovoltaic devices. Finally, photo-SECCM is used for determining structure-activity relationships for (photo)electrocatalysts of conjugated organic polymers by coupling the technique with AFM and Raman spectroscopy, suggesting the technique as a potential high throughput screening platform. The approach is exemplified by investigating poly(3-hexylthiophene) and provides not only a correlation of film morphology and photo-activity but also extracts important information on film growth and aging.

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26

Mao, Xin. "Computational exploration of high efficient catalysts for clean energy conversion." Thesis, Queensland University of Technology, 2022. https://eprints.qut.edu.au/227951/1/Xin_Mao_Thesis.pdf.

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This thesis was a computational study of designing novel catalysts for three main circles involved in electrocatalysis. The method was based on density functional theory to design a series of clean, cheap, and efficient catalysts for water circle, carbon circle, and nitrogen circle reactions. The outcomes of this thesis are expected to provide some theoretical guidance for the global energy shortage and environmental challenges.

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27

Odrowski, Sirin [Verfasser], and Werner [Akademischer Betreuer] Hofmann. "High-Energy Neutrino Scan of the Galactic Plane / Sirin Odrowski ; Betreuer: Werner Hofmann." Heidelberg : Universitätsbibliothek Heidelberg, 2012. http://d-nb.info/1178427900/34.

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28

Core, Laura. "Search for an ultra high energy neutrino diffuse flux with the ANTARES telescope." Thesis, Aix-Marseille, 2013. http://www.theses.fr/2013AIXM4130/document.

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Recherche des neutrinos de ultra haute energie avec le telescope ANTARES. Exploitations de 3 ans de donnees (2008-2011) pour la recherche d'un signal astrophysique, soit flux de Waxman Bahcall, soit neutrinos cosmogeniques. Utilization de technique d'analize multivariable
Search for ultra high energy neutrinos with ANTARES telescope. Data analysis on 3 years of lifetime (2008-2011), to look for astrophysical signal, according to Waxman-Bahcall flux or cosmogenic one. Exploitation of multivariate analysis techniques

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29

Aghababaie, Yashar. "Enhanced fluctuation-driven neutrino scattering behind supernova shocks." Thesis, McGill University, 2000. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=31179.

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We describe a general formalism for computing scattering rates of weak probes in macroscopic systems, based on a density matrix formalism. We show that weak probes in general scatter off fluctuations in the medium. In the limit that the neutrino wavelength is much larger than the lengthscale of the fluctuations, we show that the scattering rate can be calculated from knowledge of the equation of state of the medium through which the neutrinos travel. Using radial profiles of a post-bounce, shocked supernova core and a well-established equation of state for nuclear matter we compute these scattering rates for various times in the vicinity of the shock. We find that, behind the shock, these correlative effects can enhance neutrino scattering rates by factors of 8 compared to standard calculations which ignore interactions in the nuclear medium. These results may have implications for how efficiently neutrinos can restart a stalled shock, although firm conclusions regarding the ultimate effects of such an enhancement await full hydrodynamic simulations, which are not performed here.

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30

Saull, P. R. B. (Patrick Richard Behrendt). "Search for B [minus] [going to] [rho] [lepton] [anti-neutrino] at ARGUS." Thesis, McGill University, 1991. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=60511.

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Data taken with the ARGUS detector at DESY, Hamburg, specifically BB pairs produced from $e sp+e sp-$ collisions at the energy of the $ Upsilon$(4S) resonance, are used to investigate the decay channel $B sp- to rho sp0 ell sp- bar nu.$ Observation of a signal would be conclusive evidence that the CKM matrix element $V sb{ub}$ is non-zero, a necessary condition for the validity of the Kobayashi-Maskawa explanation for CP violation. The recoil mass technique is employed to try to isolate signal events. Monte Carlo data are used to model the signal background, which is dominated by reasonably well understood $b to c$ decays. Using the model of Wirbel, Stech, and Bauer, a model-dependent upper limit of 1.6 $ times$ 10$ sp{-2}$ is placed on the value of $ vert V sb{ub} vert$ at 90% confidence. The results, however, suggest that further study of the $b to c$ background is warranted. In particular, B meson transitions to states with higher mass than the $D sp*$ may contribute significantly.

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31

Farooq, Saima. "Antineutrino-induced charge current quasi-elastic neutral hyperon production in ArgoNeuT." Diss., Kansas State University, 2016. http://hdl.handle.net/2097/32845.

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Doctor of Philosophy
Department of Physics
Timothy A. Bolton
This dissertation presents the first topological study of the charge current quasi-elastic (CCQE) neutral hyperon production induced by antineutrinos in the ArgoNeuT detector, a liquid argon time projection chamber (LArTPC) at Fermilab, using 1.20 × 10²⁰ protons-on- target (POT), in the NuMI beam operating in the low energy antineutrino mode. The total cross section for the CCQE neutral hyperon production is reported at the mean production energy of 3.42 GeV. The event yield in data is consistent with the predicted cross section, σ = 2.7 × 10−40 cm²: σ(CCQE[subscript Λ0+Σ0] ) = (3.7 ± 1.9(stat.) ± 1.5 (sys.)) × 10⁻⁴⁰ cm². The study sets a 90% confidence level (C.L.) upper limit on the total cross section of CCQE neutral hyperon production: σ(CCQE[subscript Λ0+Σ0] ) < 7.3 ×10⁻⁴⁰ cm² at 90% C.L.

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32

Grégoire, Timothée. "Search for high energy neutrinos from the Galactic plane with the ANTARES neutrino telescope." Thesis, Sorbonne Paris Cité, 2018. http://www.theses.fr/2018USPCC129/document.

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Deux analyses sont présentées dans cette thèse. Une première analyse exploite les données du télescope à neutrino ANTARES pour sonder la présence d'un flux de neutrino diffus galactique. Cette analyse se base sur un modèle récent de propagation des rayons cosmiques dans la galaxie, le modèle KRAγ. Ce modèle prédit un flux de neutrinos particulièrement élevé et proche de la sensibilité des télescopes à neutrinos actuels. Il existe deux versions de ce modèle correspondant à différentes coupures sur l'énergie des rayons cosmiques, à 5 et 50 PeV/nucléon. Une méthode de maximisation d'une fonction de vraisemblance est utilisée pour prendre en compte les caractéristiques du modèle, autant spatiales qu'en énergie. Cette analyse a également été combinée avec les données de l'expérience IceCube dans le but d'exploiter au mieux les données actuelles. Des limites ont été mises sur ce modèle rejetant la version avec une coupure à 50 PeV et limitant la version avec une coupure à 5 PeV à moins de 1,2 fois le flux prédit par le modèle. Une deuxième analyse de suivi du signal d'ondes gravitationnelles GW170817 par le télescope à neutrino ANTARES est également présentée. Le signal d'onde gravitationnelles GW170817 résulte de la coalescence d'une binaire d'étoiles à neutrons. Cette deuxième analyse a pour objectif de sonder la présence d'un flux de neutrinos provenant de cet événement en cherchant des neutrinos corrélés spatialement et temporellement. J'ai pris part à cette analyse en y ajoutant les événement de type cascade. Aucun événement n'a été détecté en corrélation, des limites ont été mises sur le flux de neutrino attendu
Two analyses are detailed in this thesis. A first analysis exploit the data of the ANTARES neutrino telescope to probe the presence of a Galactic diffuse neutrino flux. This analysis is based on a recent model of cosmic ray propagation in the Galaxy, the KRAγ model. This model predict a neutrino flux particularly high and close to the sensitivity of the current neutrino telescopes. Two versions of this model exist corresponding to different cuts in the cosmic ray energy, one at 5 PeV/nucleon and an other one at 50 PeV/nucleon. A method of maximization of a likelihood function is used in order to account for the model characteristics in energy and space. The analysis has also been combined with the data of the IceCube experiment in order to exploit all the available data. Limits have been put on this model rejecting the version of the model with the 50 PeV cut and limiting the version with the 5 PeV cut to less than 1.2 times the predicted flux.A second analysis of gravitational wave signal follow-up by the ANTARES neutrino telescope is also presented in this work. The GW170817 gravitational wave signal results from the coalescence of a binary neutron star system. This second analysis aims at probing the presence of a neutrino flux coming from this event looking for neutrino events correlated in space and time. I took part to this analysis by adding the shower-like event sample. No event has been detected in correlation, limits have been put on the expected neutrino flux

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33

Pronin, Alexey. "Constraints on New Physics from Various Neutrino Experiments." Diss., Virginia Tech, 2008. http://hdl.handle.net/10919/27017.

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In this thesis we consider a number of past, present, and future neutrino experiments designed to test physics beyond the Standard Model. First, we analyze potential new physics explanations of the NuTeV anomaly and check their compatibility with the most recent experimental data. The models we consider are: gauged Lmu-Ltau, gauged B-3Lmu, and S1, S3, V1, V3 leptoquarks. We find that only the triplet leptoquark models can explain NuTeV and be compatible with the data from other experiments at the same time, and only if the components of the triplet have different masses. Then, we analyze the prospects of discovery of heavy Majorana neutrinos (neutrissimos) suggested by the Okamura model at the LHC. We find that these particles, if produced, will live short enough to decay inside of the detector, while long enough to lead to a narrow peak in the invariant mass spectrum of the decay products. We estimate the typical masses of the neutrissimos to be in the TeV range. However, studies exist that have shown that if their masses are larger than about 150 GeV then the production cross-section is too small to lead to an observable event rate. Thus, we conclude that it will not be possible to detect the neutrissimo at the LHC unless its mass is smaller that about 150 GeV which corresponds to a very small region close to the edge of the parameter space of the Okamura model. Nevertheless, we argue that the signature of the neutrissimo may be detectable in other neutrino experiments which may be carried out in the future. As examples, we consider the NuSOnG experiment, which is a fixed target neutrino scattering experiment proposed at Fermilab, and a hypothetical long-baseline neutrino oscillation experiment in which the Fermilab NUMI beam is aimed at the Hyper-Kamiokande detector in Japan. In addition to the sensitivity to neutrissimos, we analyze the capabilities of these experiments to constraint the coupling constants and masses of new particles in various models of new physics suggested in the literature. The models we consider are: neutrissimo models, models with generation distinguishing Z's such as topcolor assisted technicolor, models containing various types of leptoquarks, R-parity violating SUSY, and extended Higgs sector models. In several cases, we find that the limits thus obtained could be competitive with those expected from direct searches at the LHC. In the event that any of the particles discussed here are discovered at the LHC, then the observation, or non-observation, of these particles in the NuSOnG and Fermilab-to-Hyper-Kamiokande experiments could help in identifying what type of particle had been observed.
Ph. D.

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34

Colón, Samuel Santana. "Phenomenological model combining flavor symmetry violation and lepton number violation in neutrino physics." [Bloomington, Ind.] : Indiana University, 2008. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3334993.

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35

Basta, Marek. "Low energy photovoltaic conversion in MIND structures." Thesis, Strasbourg, 2013. http://www.theses.fr/2013STRAD019/document.

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Dispositifs photovoltaïques d'aujourd'hui convertissent l'énergie solaire en électricité de manière propre, renouvelable et inépuisable et représentent un remplacement possible pour les combustibles fossiles. Toutefois, afin de rivaliser avec les sources d'énergie classiques une augmentation significative de l'efficacité de conversion est inévitable. Dans ce travail, nous nous concentrons sur des aspects pouvant propulser le rendement de conversion au-dessus des limites de cellules présentes. La première partie de l'étude est consacrée à de nouvelles idées théoriques considérés comme le photovoltaïque de 3ème génération, alors que le plus d'intérêt est maintenu à étudier les avantages possibles de la multiplication d'électrons faible seuil. Dans la deuxième partie de l'étude, nous développons un modèle qui permet un traitement précis des propriétés optiques et de transport des structures de silicium avec des interfaces enterrées. Les analyses théoriques et expérimentales approfondies des structures existantes MIND sont ensuite effectuées. En étudiant le flux exacte et la distribution d'énergie à l'intérieur de plusieurs structures dans le cadre de leur géométrie, nous estimons les rendements quantiques possibles et les comparer avec les résultats expérimentaux. Grâce aux moyens de simulations numériques couplées avec caractérisation expérimentale, nous extrayons l'efficacité de la collecte de porteur de cellules étudiées. De nouveaux effets sont observés, une telle augmentation possible de l'efficacité de la collecte au-dessus de l'unité. Une analyse plus approfondie des résultats expérimentaux couplés avec l'étude numérique suit quelques explications classiques et non classiques de l'augmentation de l'efficacité de la collecte ou l'augmentation résultante de l'efficacité quantique. Avec la plupart des explications classiques exclu, nous concluons que l'explication la plus probable, mais non définitive de cet effet peut être interprété comme le résultat d'une multiplication des porteurs faible seuil
Photovoltaic devices of today convert solar energy into electricity in a clean, renewable and inexhaustible way and represent a possible replacement for the fossil fuels. However, in order to compete with classical energy sources a significant increase in the conversion efficiency is inevitable. In this work, we concentrate on the aspects able to raise the conversion efficiency above the limitations of present cells. The first part of the study is devoted to new theoretical ideas considered as 3rd generation photovoltaics, while the most interest is kept at studying the possible benefits of electron multiplication at low-energies. In the second part of the study, we develop a model that allows a precise treatment of optical and transport properties of silicon structures with buried interfaces. Extensive theoretical and experimental analyses of existing MIND structures are then conducted. By studying the exact flux and power distribution inside several structures in conjunction with their geometry, we estimate the possible quantum efficiencies and compare them with experimental results. Through the means of numerical simulations coupled with experimental characterization, we extract the carrier collection efficiency of studied cells. New effects are being observed, such a possible increase in collection efficiency above unity. A deeper analysis of the experimental results coupled with the numerical study analyzes several classical and non-classical explanations of the increase in collection efficiency or the resulting increase in the quantum efficiency. With most of the classical explanations ruled out, we conclude that the most probable, but not definitiveexplanation of this effect can be interpreted as the result of a low-energy carrier multiplication

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36

Petyt, David Anthony. "A study of parameter measurement in a long-baseline neutrino oscillation experiment." Thesis, University of Oxford, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.284338.

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37

Jiang, Lixue. "Structure Engineering towards High-Performance Electrodes for Electrochemical Energy Conversion and Storage." Thesis, Griffith University, 2019. http://hdl.handle.net/10072/389748.

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Major concerns about the effects of increasing fossil fuel consumption on the environment and energy security have prompted the development of sustainable and environmentally-friendly energy conversion and storage technologies based on electrochemical processes (e.g. water electrolysers, batteries and supercapacitors). Electrode materials are a key component of these technologies, and high-performance electrode systems are essential for the realization of a clean-energy-based economy. Numerous efforts have been made to develop advanced electrode materials for energy conversion and storage applications. However, current electrode synthesis methods are usually energy-intensive, not environmentally friendly, difficult to scale, or costly to produce. This thesis aims to utilize electrode structure engineering to develop highperformance electrodes based on earth-abundant materials via low-cost, energy-efficient and green synthesis strategies. Further, the applications of these electrodes in various energy conversion and storage applications are explored. Nickel-iron oxides or hydroxides are considered promising electrocatalysts for the oxygen evolution reaction, featuring a high activity and long cycling life in alkaline solution. A room temperature, electroless method has been developed here to grow nickel-iron hydroxides on a nickel foam current collector. The activity of nickel foam for the oxygen evolution reaction can be remarkably enhanced by simply immersing the nickel foam in a ferric nitrate solution at room temperature. During this process, the oxidation of the nickel foam surface by ferric nitrate ions increases the near-surface concentration of hydroxide ions, which results in the in situ deposition of a highly active, amorphous nickel-iron hydroxide layer. This phenomenon is described in Chapter 2 of this thesis. Carbon cloth is a widely-adopted current collector for the fabrication of electrodes. A facile, two-step method has been investigated here to turn commercial carbon cloth into a high-performance electrode for zinc-air batteries. Mild acid oxidation followed by air calcination directly activate carbon cloth to generate uniform, nanoporous and superhydrophilic surface structures with optimized, oxygen-rich functional groups and dramatically increased surface area. This two-step-activated carbon cloth exhibits superior bifunctional oxygen electrocatalytic activity and durability. A rechargeable, flexible zinc-air battery using the activated carbon cloth as a binder-free, flexible air electrode yields a remarkably high peak power density, high flexibility, and good cycling performance, with a small charge-discharge voltage gap. This work is elaborated in Chapter 3. Cost-effective synthesis of large-scale, uniform electrode materials with high activity and cycling stability is challenging. In Chapter 4, a reaction environment confinement strategy for scalable and reproducible production of nanostructured materials is proposed. Nickel foam is simply immersed in metal nitrate aqueous solution, with the volume of solution per unit area of nickel foam kept very low. A precisely designed reactor with a spiral tunnel ensures the same width of solution on each side of the nickel foam. The reaction environment is confined to ensure reproducible and uniform synthesis of nanostructured materials across the Ni foam. This approach has the largest REAVC (ratio of electrode area to precursor volume consumption) value reported so far, 2.0 cm2 mL-1. The synthesized nickel-iron hydroxides/nickel foam electrodes with uniformity in both microstructure and electrochemical properties exhibit remarkable activity for both the oxygen evolution reaction and hydrogen evolution reaction. Manganese oxides are a class of promising electrode materials for high performance supercapacitors. However, not all types of manganese oxides with different phases are electrochemically active, and their crystal structures have a considerable effect on their capacitance. In Chapter 5, a facile strategy is developed for the transformation of manganese oxide from the orthorhombic to birnessite crystal structure. The product exhibits significantly enhanced electrochemical performance as a supercapacitor electrode. This work opens up new possibilities for changing the crystal structure of manganese oxides towards optimized properties in electrochemical applications. This thesis makes significant contributions to our understanding of electrode structure engineering, materials science and electrochemical energy conversion and storage through: (i) designing novel nanostructured nickel-foam-based electrode systems with high electrocatalytic activity towards water oxidation via a simple immersion strategy at ambient temperature; (ii) developing facile activation procedures to endow commercially available, inactive carbon cloth with oxygen-rich functional groups and high oxygen electrocatalytic activity; (iii) controlling ion diffusion in a confined zone for uniform deposition of active materials over large-size electrodes, electrodes useful for various electrochemical applications; (iv) probing the phase transformation of manganese oxides from orthorhombic to birnessite, a material with enhanced electrochemical performance; (v) investigating the growth mechanisms of these advanced electrode materials to understand the origin of their exceptional activity.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environment and Sc
Science, Environment, Engineering and Technology
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38

COMETTI, SIMONA. "A high resolution data conversion and digital processing for high energy physics calorimeter detectors readout." Doctoral thesis, Politecnico di Torino, 2020. http://hdl.handle.net/11583/2842515.

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39

Kao, Yee. "Constraints on New Physics from Neutrino and Other Particle Experiments." Diss., Virginia Tech, 2010. http://hdl.handle.net/10919/40435.

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In this thesis we analyze a number of past, current, and future experiments to extract information on physics beyond the Standard Model. We use the Jacobi method to derive a set of simplified expressions for the probabilities of neutrino oscillations in matter. we show the possible constraints that can be placed on various models beyond the Standard Model. In several cases, we find that the limits thus thus obtained could be competitive with those expected from direct searches at the Large Hadron Collider. We then consider the possible effects of new physics beyond the Standard Model on precision measurements. In particular, we look at recent Bell/Babar results on the B meson branching fraction, and the bounds on Tau-decays from Babar. As a general framework of analyzing new physics beyond the Standard Model, we discuss what constraints can be placed on R-parity violating SUSY from these experiments. To complete our analysis, we update the single-coupling bounds on R-parity violating supersymmetry using the most up to date data as of October 2009. In addition to the data listed in the latest Review of Particle Properties, we utilize a new measurement of the weak charge of cesium-133, and preliminary Tau-decay branching fractions from Babar. Analysis of semileptonic D-decay is improved by the inclusion of experimentally measured form-factors into the calculation of the Standard Model predictions.
Ph. D.

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40

Biehl, Daniel. "Nuclear Cascades and Neutrino Production in the Sources of Ultra-High Energy Cosmic Ray Nuclei." Doctoral thesis, Humboldt-Universität zu Berlin, 2019. http://dx.doi.org/10.18452/20448.

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Der Ursprung ultra-hochenergetischer kosmischer Strahlung (UHECRs) ist eine der wichtigsten offenen Fragen der Astrophysik. Gammastrahlenblitze (GRBs) galten als potentielle Quellen, da sie zu den energetischsten Ereignissen im Universum zählen. Konventionelle Szenarien sind jedoch durch Neutrinodaten stark eingeschränkt. Außerdem weisen Messungen der chemischen Zusammensetzung kosmischer Strahlen auf schwere Kerne hin, welche in zu dichten Strahlungsfeldern disintegrieren würden. Um dieses Dilemma zu umgehen deuten neue Studien auf versteckte Beschleuniger hin, welche schwer zu detektieren sind. In dieser Dissertation präsentieren wir neue Ansätze um nukleare Prozesse in astrophysikalischen Quellen effizient und selbstkonsistent zu berechnen. Wir quantifizieren diese Wechselwirkungen anhand der nuklearen Kaskade, welche die Disintegration schwerer Kerne in leichtere Fragmente beschreibt. Auch in umfassenden Modellen, wie sie in dieser Arbeit entwickelt werden, sind GRBs durch Neutrinodaten unter Druck. Dennoch zeigen wir, dass eine Population von GRBs niedriger Luminosität konsistent mit derzeitigen Messungen ist und zugleich auch das Spektrum und die Zusammensetzung kosmischer Strahlung über den Knöchel hinweg sowie Neutrinodaten beschreiben kann. Aus unserer Prozedur können wir zusätzlich weitere Quelleneigenschaften wie die baryonische Ladung oder die Ereignisrate bestimmen. Wir zeigen weiter, dass auch von schwarzen Löchern zerrissene Sterne mögliche Kandidaten eines gemeinsamen Ursprungs der gemessenen kosmischen Strahlung und PeV-Neutrinos sind. Sie können jedoch durch kosmogenische Neutrinos von LLGRBs abgegrenzt werden. Schließlich wenden wir unser Modell auf das Gravitationswellenereignis GW170817 an. Wir zeigen für verschiedene Jet-Szenarien, dass der erwartete Neutrinofluss weit unter der Sensitivität derzeitiger Instrumente liegt. Dennoch könnten verschmelzende Neutronensterne die kosmische Strahlung unterhalb des Knöchels erklären.
The origin of Ultra-High Energy Cosmic Rays (UHECRs) is still one of the most important open questions in astrophysics. Gamma-Ray Bursts (GRBs) were considered as potential sources as they are among the most energetic events known in the Universe. However, conventional GRB scenarios are strongly constrained by astrophysical neutrino data. In addition, cosmic ray composition measurements indicate the presence of heavy nuclei, which would disintegrate if the radiation fields in the source were too dense. In order to circumvent this dilemma, recent studies point towards hidden accelerators, which are intrinsically hard to detect. In this dissertation, we present novel approaches to efficiently and self-consistently calculate the nuclear processes in astrophysical sources. We quantify these interactions by means of the nuclear cascade, which describes the subsequent disintegration of heavy nuclei into lighter fragments. Even in sophisticated source-propagation models, as the ones developed in this thesis, conventional GRBs are in tension with neutrino data. However, we demonstrate that a population of low-luminosity GRBs is not only consistent with current constraints, but can even describe the UHECR spectrum and composition across the ankle as well as neutrino data simultaneously. From our fitting procedure we can further constrain certain source properties, such as the baryonic loading and the event rate. Furthermore, we show that stars disrupted by black holes are viable candidates for a simultaneous description of cosmic ray and PeV neutrino data too. However, they can be discriminated from LLGRBs by cosmogenic neutrinos. Finally, we apply our model to GW170817. We show for different jet scenarios that the expected neutrino flux is orders of magnitude below the sensitivity of current instruments. Nevertheless, binary neutron star mergers could in principle support cosmic rays below the ankle.

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41

Gracia, Ruiz Rodrigo. "Search for populations of unresolved sources of high energy neutrinos with the ANTARES neutrino telescope." Thesis, Sorbonne Paris Cité, 2016. http://www.theses.fr/2016USPCC150/document.

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La physique des astroparticules est un domaine de la physique lié a l'étude des phénomènes astrophysiques les plus violents de l'univers comme les trous noirs dans les galaxies actives (AGN) ou les sursauts de rayons gamma (GRB), qui émettent plusieurs messagers cosmiques comme des neutrinos, des ondes gravitationnelles, des rayonnements électromagnétiques et des particules chargées. Pour mieux comprendre ces objets une approche multi-messagers est mise en place au sein de laquelle, l'observation de neutrinos cosmiques est devenue un enjeu majeur. Grâce à ses caractéristiques physiques, les neutrinos permettent d'ouvrir une nouvelle fenêtre d'observation sur l'univers lointain et de mieux comprendre les phénomènes physiques qui se produisent dans les environnements astrophysiques les plus denses.Cette thèse comporte trois grandes parties. La première partie est composée par trois chapitres consacrés au contexte scientifique dans lequel se développe le reste de la thèse. Dans le premier chapitre sont décrites les motivations scientifiques de la recherche de neutrinos cosmiques de haute énergie. Puis, dans le chapitre 2 sont décrites les caractéristiques principales des noyaux actifs de galaxie (AGN) comme sources potentielles de neutrinos. Ces sources ont été choisies comme objets "test" dans la recherche de sources potentielles. Enfin, le troisième chapitre est consacré au principe de détection et aux principaux résultats des télescopes à neutrinos en opération. La deuxième partie de la thèse est consacrée à la description technique du télescope à neutrinos ANTARES, et est composée de deux chapitres. Le chapitre 4 décrit le télescope ANTARES, l’acquisition et la sélection des données. Dans la dernière partie de ce chapitre, le travail effectué pour mesurer la perte d’efficacité des photomultiplicateurs (PMTs) en utilisant la ligne de base des taux de comptage des signaux est décrite. Le chapitre 5 est consacré à la simulation Monte Carlo. Les différents programmes de simulation utilisés par la collaboration ANTARES sont présentés, et les différents processus simulés sont décrits. Une contribution au programme officiel de génération des événements est décrite, relative à l’implémentation de la propagation des taus ainsi que l’ajout dans la simulation de 15 canaux de décroissance.La troisième partie est consacrée à la recherche de signaux cosmiques potentiels dans les événements enregistrés par ANTARES. Elle comporte 4 chapitres. Le chapitre 6 est une description de la méthode de recherche de signal, le chapitre 7 est dédié présente les principes d’une analyse fondée sur une fonction de corrélation à 2 points qui sera effectuée dans le chapitre 9 afin de chercher un éventuel excès de neutrinos cosmiques dont la distribution spatiale attendue est différente de celle des neutrinos atmosphériques. Cette méthode est particulièrement adaptée pour détecter l’effet collectif produit par des populations de sources ponctuelles faibles. Le chapitre 8 décrit la simulation du flux de neutrinos émis par des sources de type AGN. En utilisant la fonction de luminosité pour plusieurs classes d'AGN obtenu à partir d'observations en rayonnement X de ces objets et l'acceptance d'ANTARES, un ensemble de simulations de neutrinos provenant de populations d'AGN est obtenu en fonction de deux paramètres liés au nombre d'AGN dans la population et à leurs luminosités. L’analyse de ces événements avec la fonction de corrélation à deux points est détaillée dans le chapitre 9
Astroparticle physics is a branch of physics related to the study of the most violent astrophysical phenomena in the Universe such as Active Galactic Nuclei (AGN) or Gamma Ray Bursts (GRB), which emit different cosmic messengers such as neutrinos, gravitational waves, electromagnetic radiation and charged particles. A proper understanding of these objects involves then a multi-messenger approach, in which neutrinos play a fundamental role. Thanks to their physical properties, neutrinos allow us to explore the physical phenomena produced in the densest astrophysical environments and to observe the Universe at large distances. This thesis is divided into three main parts. The first part is composed by three chapters dedicated to the scientific context in which the rest of the thesis is developed. In the first chapter, the scientific motivations for the search of high energy cosmic neutrinos are described. In chapter 2, a description of the main properties of AGN are given. These sources have been chosen as "test" objects in the research of potential neutrino sources. Finally, the third chapter is dedicated to the detection principle and main results of the currently operating neutrino telescopes. The second part of the thesis is dedicated to the technical description of the ANTARES neutrino telescope, and composed of two chapters. Chapter 4 describes the ANTARES telescope, the data acquisition and the data selection. In the last part of this chapter, the work made to measure the efficiency loss of the photomultipliers (PMTs) by using the baseline rates is described. Chapter 5 is dedicated to the Monte Carlo simulations. The different simulation packages used by the ANTARES collaboration are presented, and the different simulated processes are described. A contribution to the official package for the generation of neutrino interactions, relative to the implementation of the propagation and decay of the tau leptons, is described. The third part is dedicated to the search of potential cosmic signals in the events recorded by ANTARES. It comprises four chapters. Chapter 6 is a description of the signal search method, chapter 7 presents the principles of an analysis based on a 2 point correlation function that will be applied in chapter 9 with the purpose of searching for an excess of cosmic neutrinos characterized by an expected spatial distribution which is different from that of atmospheric neutrinos. This method is well suited for the detection of the collective effect produced by populations of weak point-like sources. Chapter 8 describes the simulation of the neutrino flux emitted by AGN. By using the luminosity function for different AGN classes obtained from X-ray observations, and the ANTARES acceptance, neutrinos coming from AGN populations are simulated as a function of two parameters which are related to the number of sources in the population, and to their luminosities. The analysis of these populations with the 2 point correlation function is detailed in chapter 9

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42

Carminati, Giada <1979&gt. "Study of diffuse flux of high energy neutrinos through showers with the ANTARES neutrino telescope." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/3034/1/carminati_giada_tesi.pdf.

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43

Carminati, Giada <1979&gt. "Study of diffuse flux of high energy neutrinos through showers with the ANTARES neutrino telescope." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2010. http://amsdottorato.unibo.it/3034/.

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44

Abrego, Celestino Pete. "Measurement of high voltage using Rutherford backscattering spectrometry." Thesis, Texas A&M University, 2006. http://hdl.handle.net/1969.1/4907.

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A novel variation of Rutherford Backscattering Spectrometry (RBS) has been utilized to measure a high voltage collected on an aluminum target by Direct Energy Conversion. The maximum high voltage on the target was measured to be 97.5 kV +/- 2 kV. The resistance of the circuit was then calculated based on the current driving different target voltages. The resistance was calculated to be 199.4GÃÂ© +/- 5%. It was shown that by simply measuring the neutral particlesÃ¢ÂÂ energy spectra, the voltage on the target and resistance of the circuit can be found with certainty. The experimental data agree well with previous work and with the scattering theory developed. Thus, the capability of RBS has been extended to measure high voltages generated by direct energy conversion; this is something that has not been done before.

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45

Reimann, René [Verfasser], Christopher Henrik V. [Akademischer Betreuer] Wiebusch, and Philipp [Akademischer Betreuer] Mertsch. "Search for the sources of the astrophysical high-energy muon-neutrino flux with the IceCube neutrino observatory / René Reimann ; Christopher Wiebusch, Philipp Mertsch." Aachen : Universitätsbibliothek der RWTH Aachen, 2019. http://d-nb.info/1214721532/34.

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46

Muhammad, Musbahu. "High gain non-isolated DC-DC converter topologies for energy conversion systems." Thesis, University of Newcastle upon Tyne, 2017. http://hdl.handle.net/10443/3665.

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Emerging applications driven by low voltage level power sources, such as photovoltaics, batteries and fuel cells require static power converters for appropriate energy conversion and conditioning to supply the requirements of the load system. Increasingly, for applications such as grid connected inverters, uninterruptible power supplies (UPS), and electric vehicles (EV), the performance of a high efficiency high static gain power converter is of critical importance to the overall system. Theoretically, the conventional boost and buck-boost converters are the simplest non-isolated topologies for voltage step-up. However, these converters typically operate under extreme duty ratio, and severe output diode reverse recovery related losses to achieve high voltage gain. This thesis presents derivation, analysis and design issues of advanced high step-up topologies with coupled inductor and voltage gain extension cell. The proposed innovative solution can achieve significant performance improvement compared to the recently proposed state of the art topologies. Two unique topologies employing coupled inductor and voltage gain extension cell are proposed. Power converters utilising coupled inductors traditionally require a clamp circuit to limit the switch voltage excursion. Firstly, a simple low-cost, high step-up converters employing active and passive clamp scheme is proposed. Performance comparison of the clamps circuits shows that the active clamp solution can achieve higher efficiency over the passive solution. Secondly, the primary detriment of increasing the power level of a coupled inductor based converters is high current ripple due to coupled inductor operation. It is normal to interleaved DC-DC converters to share the input current, minimize the current ripple and increase the power density. This thesis presents an input parallel output series converter integrating coupled inductors and switched capacitor demonstrating high static gain. Steady state analysis of the converter is presented to determine the power flow equations. Dynamic analysis is performed to design a closed loop controller to regulate the output voltage of the interleaved converter. The design procedure of the high step-up converters is explained, simulation and experimental results of the laboratory prototypes are presented. The experimental results obtained via a 250 W single phase converter and that of a 500 W interleaved converter prototypes; validate both the theory and operational characteristics of each power converter.

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47

Gordon, Jacob William Hunter. "A Binned Search for Ultra High Energy Neutrinos with Data from the Third Flight of the Antarctic Impulsive Transient Antenna." The Ohio State University, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=osu1515037109386367.

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48

Pestes, Rebekah Faith. "Precision Neutrino Oscillations: Important Considerations for Experiments." Diss., Virginia Tech, 2021. http://hdl.handle.net/10919/103527.

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Currently, we are in an era of neutrino physics in which neutrino oscillation experiments are focusing on doing precision measurements. In this dissertation, we investigate what is important to consider when doing these precise experiments, especially in light of significant unresolved anomalies. We look at four general categories of considerations: systematic uncertainties, fundamental assumptions, parameterization-dependence of interpretations, and Beyond the Standard Model (BSM) scenarios. By performing a simulation using GLoBES, we find that uncertainties in the fine structure of the reactor neutrino spectrum could be vitally important to JUNO, a reactor neutrino experiment being built in China, so a reference spectrum with comparable energy resolution to JUNO is needed in order to alleviate this uncertainty. In addition, we determine that with their fix of the fine structure problem, JUNO can test the existence of a quantum interference term in the oscillation probability. We also reason that the CP-violating phase is very parameterization dependent, and the Jarlskog invariant is better for talking about amounts of CP violation in neutrino oscillations. Finally, we discover that CP-violating neutrino Non-Standard Interactions (NSIs) could already be affecting the outcomes of T2K and NOνA, two accelerator neutrino experiments, and may be why there is a tension in these two data sets.
Doctor of Philosophy
Neutrinos are very weakly interacting, fundamental particles that are extremely plentiful in the universe. There are three known types (or flavors) of neutrinos, and the fact that they change flavors (or oscillate) informs us that their mass is not zero, but no experiments have been able to put a lower bound on the smallest neutrino mass. Now that experiments measuring neutrino oscillations have become more precise and some significant anomalies remain unresolved, there are considerations that have become important to investigate. In this paper, we look at four of these considerations: • Uncertainties in the finer shapes in the energy spectrum of neutrinos coming from a nuclear reactor (Chapter 2): We find that these uncertainties could destroy the ability of the Jiangmen Underground Neutrino Observatory (JUNO) to meet one of its major goals, unless they measured the spectrum at a spot close to the reactor with a really good energy resolution (comparable to that of JUNO). • An assumption about quantum mechanics being the foundation of particles and their interactions (Chapter 3): We determine that by heeding our warning in Chapter 2, JUNO will be able to test the existence of the term in the oscillation probability arising out of quantum interference. • How the neutrino oscillation parameter known as the CP-violating phase is dependent on the parameterization scheme used for the matrix describing how the flavors mix to make neutrino oscillation possible (Chapter 4): We find that the parameterization dependence is drastic, and if we want to discuss how much CP violation (i.e. a measure of how neutrinos behave differently from their anti-matter counterparts) exists in neutrino oscillations, we should talk about a quantity called the Jarlskog invariant. • The possibility of interactions existing between neutrinos and other particles that are not part of the Standard Model of Particle Physics, i.e. neutrino Non-Standard Interactions (NSIs) (Chapter 5): We discover that NSIs that are CP-violating can actually explain a current discrepancy between two neutrino oscillation experiments: Tokai to Kamioka Nuclear Decay Experiment (T2K) and NuMI Off-axis ν e Appearance (NOνA).

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49

Héritier, Carole. "Identification et localisation des événements neutrino dans le détecteur OPERA." Phd thesis, Université Claude Bernard - Lyon I, 2004. http://tel.archives-ouvertes.fr/tel-00009860.

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OPERA est une expérience destinée à démontrer que le phénomène d'oscillation des neutrinos est à l'origine des neutrinos atmosphériques (transition $\nu_\mu \to \nu_\tau$ et recherche de l'angle de mélange $\nu_\mu \to \nu_e$). Pour prouver l'apparition des à 732 km du CERN, un détecteur hybride est en cours d'installation dans le souterrain du Gran Sasso. La cible, faite de briques de 8kg composées de feuilles de plomb et d'émulsions photographiques, permet l'observation directe de la désintégration du lepton $\tau$ produit lors des interactions $\nu_\tau$ en courant chargé (CC). La reconstruction des traces, la localisation des interactions neutrino dans la cible ainsi que l'identification du muon sont possibles par des trajectographes placés à l'intérieur de la cible (plans de scintillateurs) et dans le spectromètre qui la suit (détecteurs RPC). Cette thèse est centrée sur le développement des algorithmes nécessaires pour l'identification et la localisation des interactions neutrino dans la cible d'OPERA. Ces algorithmes sont basés sur une approche globale de l'utilisation des détecteurs électroniques. Une classification des événements neutrino est mise en place à partir du muon produit lors des interactions $\nu_\tau$ CC avec désintégration du tau en muon. Elle est optimisée par la reconstruction de traces et par la prise en compte de critères topologiques et calorimétriques reflétant la nature de l'interaction (quasi-élastique, profondément inélastique) ; la logique de localisation de la brique d'interaction est alors adaptée à chaque catégorie. Une carte tridimensionnelle de probabilités de briques est obtenue et donne ainsi la possibilité d'élaborer différentes stratégies d'extraction de briques. Dans cette continuité de ce travail, une étude de faisabilité d'un test sur faisceau appelé OPERETTE a été réalisée. Le projet consistait à installer un détecteur similaire à celui d'OPERA sur un faisceau de neutrinos dans la zone Nord du CERN. OPERA aurait ainsi disposé d'un lot d'événements neutrino avant son démarrage lui permettant de tester les différentes techniques d'analyse.

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50

Cox, David Christopher. "A measurement of the neutral current neutrino-nucleon elastic cross section at MiniBooNE." [Bloomington, Ind.] : Indiana University, 2008. http://gateway.proquest.com/openurl?url_ver=Z39.88-2004&rft_val_fmt=info:ofi/fmt:kev:mtx:dissertation&res_dat=xri:pqdiss&rft_dat=xri:pqdiss:3297941.

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Thesis (Ph.D.)--Indiana University, Dept. of Physics, 2008.
Title from dissertation home page (viewed Sept. 30, 2008). Source: Dissertation Abstracts International, Volume: 69-03, Section: B, page: 1710. Adviser: Rex Tayloe.

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