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TORRI, MARCO DANILO CLAUDIO. "LORENTZ INVARIANCE VIOLATION EFFECTS ON ULTRA HIGH ENERGY COSMIC RAYS PROPAGATION: A GEOMETRICAL APPROACH." Doctoral thesis, Università degli Studi di Milano, 2019. http://hdl.handle.net/2434/625711.
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Cosmic rays are highly energetic extraterrestrial particles, mainly originated outside the Solar system, with energy that spans many decades. Since they include the most energetic particles, accessible nowadays, it is very interesting to study this kind of radiation, that constitute a significant source of informations about astrophysical objects. Moreover these highly energetic particles propagate for cosmological distances, so they can furnish a deeper understanding of the physical mechanisms of the universe. Hence it results very important to obtain a deeper understanding of the so called GZK “puzzle”. Universe results opaque to the propagation of the highest energetic particles, because of their interaction with the Cosmic Microwave Background Radiation (CMBR). Therefore the sources of these Ultra High Energy Cosmic Rays (UHECR) must be collocated inside a foreseen opacity sphere (GZK effect). But some recent experimental observations seem to indicate the possibility that certain UHECR correlate with candidate sources collocated farther than expected.
One of the most interesting possible explanations of this GZK suppression “puzzle” consists in introducing a particle kinematics modification, assuming this effect as a relic of the supposed quantum structure of space-time. In this respect, physics is amended by the introduction of small perturbations to the Lorentz symmetry, the so called Lorentz Invariance Violation (LIV) scenario. In this work, to preserve the idea of space-time homogeneity and isotropy, a possible way to introduce a LIV theory, without a preferred class of inertial observers, is explored. The Lorentz symmetry is therefore only modified, as in Doubly Special Relativity theories. Thus the idea of space-time isotropy results restored respect to the new amended Lorentz transformations, here introduced. Hence it results possible to solve the GZK “puzzle” without the necessity of the introduction of a privileged class of inertial observers.
The geometry of space-time is constructed starting from the momentum space modified structure, determined by the amended particle kinematics. The resultant geometry is of Finsler type, with an acquired energy dependance. The Lorentz group is then modified, in order to preserve space-time isotropy. The particle Standard Model results modified, but it still preserve the symmetry structure of the ordinary one, as shown proving the validity of the Coleman-Mandula theorem, with the substitution of the ordinary Lorentz group with the modified one. Finally the model is employed to compute phenomenological predictions on the behavior of UHECR and even of high energy neutrinos.
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Blanco-Pillado, José Juan. "Topological defects and ultra-high energy cosmic rays /." Thesis, Connect to Dissertations & Theses @ Tufts University, 2001.
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Thesis (Ph.D.)--Tufts University, 2001.Adviser: Alexander Vilenkin. Submitted to the Dept. of Physics. Includes bibliographical references (leaves 108-114). Access restricted to members of the Tufts University community. Also available via the World Wide Web;
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Taylor, Andrew Martin. "The propagation of ultra high energy cosmic rays." Thesis, University of Oxford, 2007. http://ora.ox.ac.uk/objects/uuid:63572ebe-fb32-41b6-8b91-a7294db135a6.
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This thesis presents theoretical work on the propagation of ultra high energy cosmic rays, from their source to Earth. The different energy loss processes, resulting from cosmic ray interactions with the radiation fields, are addressed. The subsequent uncertainties in the energy loss rates and the effect produced on the arriving cosmic ray spectrum are highlighted. The question of the composition of ultra high energy cosmic rays remains unresolved, with the range of possibilities leading to quite different results in both the secondary fluxes of particles produced through cosmic ray energy loss interactions en route, and the arriving cosmic ray spectra at Earth. A large range of nuclear species are considered in this work, spanning the range of physically motivated nuclear types ejected from the cosmic ray source. The treatment of cosmic ray propagation is usually handled through Monte Carlo simulations due to the stochastic nature of some of the particle physics processes relevant. In this work, an analytic treatment for cosmic ray nuclei propagation is developed. The development of this method providing a deeper understanding of the main components relevant to cosmic ray nuclei propagation, and through its application, a clear insight into the contributing particle physics aspects of the Monte Carlo simulation. A flux of secondary neutrinos, produced as a consequence of cosmic ray energy loss through pion production during propagation, is also expected to be observed at Earth. This spectrum, however, is dependent on several loosely constrained factors such as the radiation field in the infrared region and cosmic ray composition. The range of possible neutrino fluxes obtainable with such uncertainties are discussed in this work. High energy cosmic ray interactions with the radiation fields present within the source may also occur, leading to cosmic ray energy loss before the cosmic ray has even managed to escape. The secondary spectra produced are investigated through the consideration of three candidate sources. A relationship between the degree of photo-disintegration in the source region and the neutrino flux produced through p γ interactions is found.
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Brobeck, Elina Stone Edward McKeown R. D. "Measurement of ultra-high energy cosmic rays with CHICOS /." Diss., Pasadena, Calif. : California Institute of Technology, 2009. http://resolver.caltech.edu/CaltechETD:etd-10192008-143041.
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Lundanes, Ingvild Olsen. "The propagation and energy losses of ultra high energy cosmic rays." Thesis, Norges teknisk-naturvitenskapelige universitet, Institutt for fysikk, 2011. http://urn.kb.se/resolve?urn=urn:nbn:no:ntnu:diva-12654.
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This project investigates the propagation of ultra-high energy cosmic raynuclei and protons. A simulation of the propagation subjecting the particlesto energy losses due to cosmological redshift as well as interactions with theextra-galactic background radiation seeks to find the initial conditions at thesource which give the best results on Earth compared to the observations ofthe Pierre Auger Observatory (PAO).The results agree with previous works of the same kind that a chemicalcomposition of medium-weight fits the observed air shower data best. Thestarting conditions which gave the best results for the air shower characteristics
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Barbot, Cyrille. "Super-heavy X-particle decay and ultra-high energy cosmic rays." [S.l. : s.n.], 2003. http://deposit.ddb.de/cgi-bin/dokserv?idn=969379846.
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Khanin, Alexander. "Bayesian methods for the analysis of ultra-high-energy cosmic rays." Thesis, Imperial College London, 2016. http://hdl.handle.net/10044/1/42034.
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The origins of ultra-high-energy cosmic rays (UHECRs) are one of the open puzzles of astrophysics. A number of plausible candidates, such as active galactic nuclei (AGNs) have been discussed, but no clear consensus has been reached. One way to assess the different hypotheses is by analyzing the UHECR arrival directions. Recently, a small number of studies have begun applying Bayesian methodologies to this problem, forming the first steps in the development of a comprehensive Bayesian framework for the study of UHECRs. In this work, we have developed two Bayesian methods to study this question, and have applied them to UHECRs from the Pierre Auger Observatory (PAO). The first method was a Bayesian approach to studying the catalogue-independent clustering of UHECRs. Previously, this had been difficult as there is no well motivated clustered model that can be used in a Bayesian model comparison. We have resolved this difficulty by developing a multi-step approach that derives such a model from a sub-set of the data. This approach could have broad applications for anisotropy searches in other areas of astronomy. Our results were consistent with both isotropic and clustered models. The second was a Bayesian method that was aimed to find associations between UHECR arrival directions and source catalogues. It was an extension of a previous Bayesian study, but analyzed a greater data set, used a more refined UHECR model, and was generalized to be applicable to a greater variety of source catalogues. Our results were broadly consistent with previous work, with the purely isotropic UHECR models being disfavoured for reasonable parameter ranges. It will be of great interest to apply our methods to samples of greater size. The extended UHECR samples that will be available in the near future should be sufficient for our methods to determine the origins of the UHECRs.
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Morris, Chad Michael. "Detection Techniques of Radio Emission from Ultra High Energy Cosmic Rays." The Ohio State University, 2009. http://rave.ohiolink.edu/etdc/view?acc_num=osu1254506832.
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Rodrigues, Xavier. "Blazars as Sources of Neutrinos and Ultra-high-energy Cosmic Rays." Doctoral thesis, Humboldt-Universität zu Berlin, 2019. http://dx.doi.org/10.18452/20610.
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Der Ursprung ultra-hochenergetischer kosmischer Strahlung (UHECRs) ist immer noch unbekannt. Neutrinoteleskope wie IceCube messen einen Fluss hochenergetischer astrophysikalischer Neutrinos, dessen erwarteter Ursprung Wechselwirkungen kosmischer Strahlung (CR) ist. Jedoch scheinen die Ankunftsrichtungen der beobachteten Neutrinos nicht signifikant mit den Koordinaten bekannter, hochenergetischer astrophysikalischer Quellen zu korrelieren. Wir tragen zum Verständnis dieses Problems durch die Untersuchung von Blazaren, eine Klasse aktiver Galaxienkerne, bei. Motiviert durch Hinweise, dass ein Teil der UHECRs schwerer als Protonen ist, modellieren wir die Wechselwirkungen einer Population beschleunigter Kerne mit den umgebenden Photonfelder in Blazaren. Wir folgern, dass in Blazaren niedriger Luminosität beschleunigte CRs nicht effizient wechselwirken. In hellen Blazaren sind photo-hadronische Wechselwirkungen effizient, was zu starker Neutrinoproduktion und zur Entwicklung einer nuklearen Kaskade führt. Wir berechnen die Neutrinoemission der gesamten Verteilung von Blazaren, und folgern, dass eine Population niedriger Luminosität, die derzeit nicht beobachtet, aber theoretisch erwartet wird, den gesamten IceCube-Fluss bei den höchsten Energien erklären kann. Weiterhin modellieren wir den Blazar TXS 0506+056, aus dessen Richtung ein Neutrino während einer Phase erhöhter elektromagnetischer Aktivität detektiert wurde. Wir testen die Hypothese, dass ein Signal von 13+/-5 Neutrinos, die in IceCube aus der selben Richtung im Jahr 2014-15 gemessen wurden, von der selben Quelle stammt. Unser Modell kann höchstens 5 Ereignisse erklären. Schließlich untersuchen wir das erste beobachte Ereignis verschmelzender Neutronensterne, GW170817, als CR-Beschleuniger. Wir modellieren die Quelle und zeigen, dass Radio- und Röntgenmessungen strikte Beschränkungen der magnetischen Feldstärke nach sich ziehen. Wir zeigen, dass diese Quelle in der Lage ist, CRs zu emittieren.The origin of ultra-high-energy cosmic rays (UHECRs) is still unclear. Neutrino telescopes like IceCube have observed a flux of high-energy cosmic neutrinos, expected to originate in cosmic ray (CR) interactions. However, their arrival directions do not statistically correlate with the positions of known high-energy astrophysical sources. In this thesis we explore blazars, a class of active galaxies, as potential UHECR accelerators. Motivated by evidence that a fraction of the UHECRs are heavier than protons, we model the interactions of CR nuclei with the photon fields present in blazars, in order to estimate the emitted neutrino and UHECR spectrum. We conclude that in dim blazars, accelerated CRs do not interact efficiently due to the low photon density, but instead escape the source unscathed. In bright blazars, photo-hadronic interactions are more efficient, leading to abundant production of neutrinos and lighter nuclei. We use this model to quantify the neutrino emission from the entire cosmological blazar population. We conclude that low-luminosity blazars currently unobserved but expected theoretically, can explain the entire IceCube flux at the highest energies. We then focus on blazar TXS 0506+056, from whose direction a neutrino was recently detected during an electromagnetic flaring state. We test the hypothesis that a signal of 13+/-5 neutrinos observed by IceCube from the same direction in 2014-15 may have originated in the same source. Given the constraints from multi-wavelength observations, this model can explain at most 5 neutrino events. Finally, we study the remnant of the first neutron star merger ever observed, object GW170817. We model the particle interactions in the source and show that multi-wavelength observations can provide a constraint on the magnetic field strength. We estimate that this source may be an efficient CR emitter, which shows the importance of future multi-messenger observations to better constrain this source type.
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Smith, Nigel James Telfer. "A search for ultra high energy gamma ray sources from the South Pole." Thesis, University of Leeds, 1990. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.291023.
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LaHurd, Danielle V. "Searching for Quark Gluon Plasma Signatures in Ultra High Energy Cosmic Rays." Case Western Reserve University School of Graduate Studies / OhioLINK, 2017. http://rave.ohiolink.edu/etdc/view?acc_num=case1479298851843212.
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Burton, Ross E. "Upper Limits on the Ultra-High Energy Cosmic Ray Flux from Unresolved Sources." Case Western Reserve University School of Graduate Studies / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=case1323452264.
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Dundovic, Andrej [Verfasser], and Günter [Akademischer Betreuer] Sigl. "On Anisotropies of Ultra-high Energy Cosmic Rays / Andrej Dundovic ; Betreuer: Günter Sigl." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2018. http://d-nb.info/1162275243/34.
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Mottram, M. J. "A search for ultra-high energy neutrinos and cosmic-rays with ANITA-2." Thesis, University College London (University of London), 2012. http://discovery.ucl.ac.uk/1344072/.
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The ANtarctic Impulsive Transient Antenna (ANITA) experiment is a balloon-borne array of radio antennas designed to search for ultra-high energy neutrinos by observing the Antarctic ice sheet for radio emission that is expected to arise as a result of the neutrinos’ interaction. ANITA is further able to detect radio emission that arises when ultra-high energy cosmic-rays interact in the Earth’s atmosphere. The second flight of the experiment, ANITA-2, took place in 2008-09 over 31 days. This thesis describes an analysis of the ANITA-2 dataset and presents results from searches for ultra-high energy neutrinos and cosmic-rays. No statistical evidence of emission from neutrino interactions is observed, with two candidate events discovered on a background of 1:13 \pm 0:27. A limit on the diffuse flux of ultra-high energy neutrinos is presented, further model-independent and model-dependent flux limits on selected active galactic nuclei are calculated. Four isolated and one non-isolated cosmic-ray candidates are discovered. The identity of the isolated candidates as cosmic-ray-induced radio emission is confirmed through correlation between observed and expected emission polarisation.
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Oikonomou, F. "Constraining the sources of ultra-high energy cosmic rays with multi-messenger data." Thesis, University College London (University of London), 2014. http://discovery.ucl.ac.uk/1450249/.
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Ultra-high energy cosmic rays (UHECRs) are cosmic rays with energy exceeding 10¹⁸ electronvolts. The sources of these particles remain unknown despite decades of research. This thesis presents a series of studies aimed at constraining the sources of UHECRs both directly by studying their observed arrival directions and indirectly through their expected secondary gamma-ray signatures. An analysis of the arrival direction distribution of the highest energy cosmic rays detected at the Pierre Auger Observatory is presented. The aim of the study was to determine whether the arrival directions of observed UHECRs follow the distribution of nearby extragalactic sources, which is expected if UHECRs are light nuclei of extragalactic origin. A departure from isotropy at the 95% level is observed but no clear correlation with the extragalactic matter distribution is found. The sensitivity of upcoming UHECR experiments, with an order of magnitude higher annual exposure than current experiments, to the expected UHECR anisotropy has been investigated through simulations. It is shown, that with five years of data from such a detector an anisotropy should be detectable at the 99% level as long as the composition is proton dominated. In a scenario where the UHECR source distribution is strongly clustered, similar to the distribution of galaxy clusters, an anisotropy at the 99.9% level is expected even if the fraction of protons at the highest energies is as low as 30%. Constraints on the sources of UHECRs may also come from the secondary particles that UHECRs produce during their propagation. A study of the expected secondary gamma-ray signatures of UHECR accelerators embedded in magnetised environments is presented. The secondary gamma-ray emission expected in this model is shown to be consistent with the spectra of a number of extreme blazars. It is shown that this model is more robust to variations of the overall extragalactic magnetic eld strength than other proposed scenarios, which is appealing in view of the large uncertainty surrounding the strength and con guration of extragalactic magnetic fi elds.
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Lang, Rodrigo Guedes. "Effects of Lorentz invariance violation on the ultra-high energy cosmic rays spectrum." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/76/76131/tde-13042017-143220/.
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Relativity is one of the most important and well tested theories and Lorentz invariance is one of its pillars. Lorentz invariance violation (LIV), however, has been discussed in several quantum gravity and high energy models. For this reason, it is crucial to test it. Several tests, both terrestrial and astrophysical, have been performed in the last years and provide limits on the violation. This work takes part in these efforts and discuss the possibility of testing LIV with ultra-high energy cosmic rays (UHECRs). The effects of LIV in their propagation and the resulting changes in the spectrum of UHECRs are obtained and compared to the experimental data from the Pierre Auger Observatory. An analytical calculation for the inelasticity in the laboratory frame with LIV of any a + b → c + d interaction is presented and used to obtain the phase space and the energy losses of the pion production for protons, the photodisintegration for nuclei and the pair production for photons with LIV. A parametrization for the threshold energy of the photodisintegration with LIV is also proposed. The main effect seen is a decrease in the phase space and a resulting decrease in the energy loss. These changes have been implemented in Monte Carlo propagation codes and the resulting spectra of protons, nuclei and photons on Earth have been obtained and fitted to the data from the Pierre Auger Observatory. It is shown that upper limits on the photon LIV coefficient can be derived from the upper limits on the photon flux from the Pierre Auger Observatory.Relatividade é uma das mais importantes e bem testadas teorias e a invariância de Lorentz é um de seus pilares. A violação da invariância de Lorentz (VIL), todavia, tem sido discutida em diversos modelos de gravidade quântica e altas energias. Por tal motivo, é crucial testá-la. Diversos testes, tanto terrestres quanto astrofísicos, foram realizados nos últimos anos e fornecem limites na violação. Este trabalho se insere nesses esforços e discute a possibilidade de testar VIL com raios cósmicos de altíssima energia. Os efeitos da VIL em sua propagação e as consequentes mudanças no espectro de raios cósmicos de altíssima energia são obtidos e comparados com os dados experimentais do Observatório Pierre Auger. Um cálculo analítico para a inelasticidade no referencial do laboratório com VIL para qualquer interação da forma a + b → c + d é apresentado e usado para obter o espaço de fase e as perdas de energia para a produção de píons para prótons, a fotodesintegração para núcleos e a produção de pares para fótons com VIL. Uma parametrização para o limiar de energia da fotodesintegração com VIL também é proposta. O principal efeito observado é uma diminuição no espaço de fase e uma consequente diminuição nas perdas de energia. Tais mudanças foram implementadas em códigos de Monte Carlo para a propagação e os espectros resultantes para prótons, núcleos e fótons na Terra foram obtidos e ajustados aos dados do Observatório Pierre Auger. É mostrado que limites superiores nos coeficientes de VIL para o fóton podem ser deduzidos dos limites superiores para o fluxo de fótons do Observatório Pierre Auger.
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Morejon, Leonel. "New Interaction Models of Ultra-high-energy Cosmic Rays from a Nuclear Physics Approach." Doctoral thesis, Humboldt-Universität zu Berlin, 2021. http://dx.doi.org/10.18452/22585.
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Der Ursprung der ultrahochenergetischen kosmischen Strahlung (UHECRs) benötigt Modelle der photonuklearen kosmischen Strahlungsinteraktionen. In dieser Arbeit stelle ich Modelle vor, die drei Aspekte der Modellierung der Hochenergie-Astronuklearphysik verbessern: die Photomesonenproduktion durch Kerne der kosmischen Strahlung, die schwerer als Protonen sind, die Gammastrahlenemission von instabilen Kernen, die durch den Photodisintegrationsprozess der kosmischen Strahlung erzeugt werden, und die Simulation der extragalaktischen Ausbreitung von Kernen, die schwerer als Eisen sind (sogenannte superschwere Isotope). Das Photomesonenmodell ist das erste in der Literatur, das über das einfache Prinzip der Nukleonen-Superposition hinausgeht. Es liefert eine detailliertere Beschreibung der inelastischen Wirkungsquerschnitte und des emittierten Spektrums von Sekundärteilchen, einschließlich Isotopen und Pionen, die zu Photonen und Neutrinos führen. Die Auswirkungen des Modells werden in Simulationen von Gammastrahlenausbrüchen und Gezeitenstörungsereignissen gezeigt, und es beeinflusst signifikant die hochenergetische Neutrinoemission, die chemische Zusammensetzung und das Spektrum der emittierten UHECRs. Das zweite Modell beschreibt die Photoproduktion aus den De-Exzitationen und Zerfällen instabiler Kerne, die aus dem Photozerfall der kosmischen Strahlung in Wechselwirkung mit astrophysikalischen Photonen resultieren sollen. Ihre Wirkung wird am Photoemissionsspektrum des Kerns von Centaurus A veranschaulicht und mit ähnlichen Arbeiten verglichen, mit denen es Unstimmigkeiten gibt. Schließlich wird der Photodesintegration von UHECR überschweren Kernen diskutiert. Eine Wechselwirkungstabelle wird unter Verwendung von Querschnitten aus TALYS konstruiert, und die Wechselwirkungsraten werden im Zusammenhang mit der extragalaktischen Ausbreitung berechnet. Überschwere Kerne breiten sich in bestimmten Energiebereichen weiter aus als leichtere Kerne.The origin of the ultra-high-energy cosmic rays (UHECRs) is still unknown. Photonuclear interactions of cosmic rays are key to understanding this problem in a multimessenger context. Nuclear physics insights are crucial in building accurate models to interpret the data that indicates UHECR can be heavier than protons. This thesis presents models that improve three aspects of high-energy astronuclear physics modelling: photomeson production by cosmic-ray nuclei heavier than protons, gamma-ray emission from unstable nuclei created by the photodisintegration of cosmic rays, and the simulation of extragalactic propagation of nuclei heavier than iron (so-called superheavy isotopes). The photomeson model is the first in the literature to go beyond the simple principle of nucleon superposition. It provides a more accurate description of the inelastic cross sections, and the emitted spectrum of secondary particles, including isotopes and pions which lead to photons and neutrinos.The model’s impact is shown in simulations of gamma-ray bursts and tidal disruption events, and it affects significantly the high-energy neutrino emission, the chemical composition and the spectrum of the emitted UHECRs. The second model describes photoproduction from de-excitations and decay of unstable nuclei, which are expected to be produced in photo-disintegration of cosmic rays interacting with astrophysical photons. Its impact is illustrated in the photo-emission from the core of the Centaurus A and compared to similar works with which is in disagreement. This supports the need for sufficiently accurate models. Lastly, the photodisintegration of UHECR superheavy nuclei is discussed. An interaction table is produced with cross sections obtained from TALYS and the interaction rates computed in the context of extragalactic propagation. Superheavy nuclei propagate further than lighter nuclei in certain energy ranges. The models developed are publicly available as open-source software.
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Wiedemann, Christin. "A search for ultra-high energy neutrinos with AMANDA-II." Doctoral thesis, Stockholm : Physics Department, Stockholm university, 2007. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-7151.
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Schumacher, Lisa Johanna [Verfasser], Christopher Henrik V. [Akademischer Betreuer] Wiebusch, and Antoine [Akademischer Betreuer] Kouchner. "Search for the common sources of high-energy cosmic neutrinos and ultra-high-energy cosmic rays / Lisa Johanna Schumacher ; Christopher Wiebusch, Antoine Kouchner." Aachen : Universitätsbibliothek der RWTH Aachen, 2021. http://d-nb.info/1238365329/34.
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Viberg, Fredrik. "Advanced algorithms for Ultra-High-Energy Cosmic Ray Detection with the EUSO-TA Experiment." Thesis, Luleå tekniska universitet, Institutionen för system- och rymdteknik, 2016. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-313.
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Cosmic rays at energies 10^18 eV and above are known as Ultra High Energy Cosmic Rays (UHECR). UHECR are charged particles that are accelerated by the biggest accelerators in our universe. Candidate accelerators generating these UHECR are super novas, black holes and neutron stars. But where and what these intergalactic accelerators is at large still unknown. One of the experiments in the forefront of research in this eld is JEM-EUSO, a planed space based telescope for detecting UHECR particles as they enter Earth's atmosphere. Made possible by the advances in photon detectors and light weighted Fresnel lenses. A ground based path nder experiment was carried out in 2015 called EUSO-TA to test the optics and photomultiplier technologies. When the UHECR enters the atmosphere it collides with the atoms generating a number of secondary particles which in turn interacts with other atoms in the atmosphere generating a cascade of secondary particles. These trails are known as Extensive Air Showers (EAS). Mostly electrons are generated and in turn they excites the nitrogen atoms in the atmosphere which generate a isotropic characteristic uorescence light. The JEM-EUSO telescope is designed to detect and measure the photon ux. From the photon ux it will be able to estimate the energy of the initial UHECR. JEM-EUSO will cover the largest area of EAS search and increase statistics of UHECR data. This thesis describes the method and development of algorithms made for EAS analysis and detection based on EUSO-TA data. A simulation of EUSO-TA focal surface was developed, simulating background, stars and EAS. The algorithms developed involves a background subtracting lter, line detection using Hough transform and a neural network for decision making. The Hough transform is used in computer vision and is a method used to detect lines in the pictures. It successfully identi ed both simulated and captured UHECR incoming direction with small errors. Neural network are a machine learning method used classi cation and regression problems. With the use of know example data simulated or real captured data a neural network can without explicit programing it, adjust its parameters to t the data. Based on method called supervised learning. The algorithms was programed in Python and using ROOT software to build the neural network. The resulting algorithm was able to successfully detect simulated data. Test on the EUSO-TA captured data shows a promising result but has to be developed and tested further.
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Heimann, Philipp [Verfasser]. "A test for the existence of protons in ultra-high energy cosmic rays / Philipp Heimann." Siegen : Universitätsbibliothek der Universität Siegen, 2018. http://d-nb.info/117520546X/34.
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CASTRO, MARY LUCIA DIAZ. "INTRINSIC FLUCTUATIONS OF EXTENSIVE AIR SHOWERS AND THE CHEMICAL COMPOSITION OF ULTRA HIGH ENERGY COSMIC RAYS." PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIRO, 2012. http://www.maxwell.vrac.puc-rio.br/Busca_etds.php?strSecao=resultado&nrSeq=19921@1.
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PONTIFÍCIA UNIVERSIDADE CATÓLICA DO RIO DE JANEIROO Observatório Pierre Auger é um detector de raios cósmicos ultra-energéticos (E maior ou igual 1018 eV) com características híbridas, que combinam detectores de superfície e de fluorescência. A determinação da composição química primária destes raios cósmicos é um dos seus principais objetivos. Há indícios de que os primários dos raios cósmicos com E maior que 1018.5 eV tem massa maior, conclusão baseada nos resultados recentes sobre a evolução dos chuveiros atmosféricos extensos (cascatas de partículas formadas quando da colisão do raio cósmico primário no topo da atmosfera com moléculas de N2 ou O2). Encontrar parâmetros, que caracterizam o chuveiro, no processo de sua reconstrução e que forneçam informações associadas a este resultado, são essenciais para validar esta conclusão. Nesta tese estuda-se a evolução como função da energia, de parâmetros que caracterizam os chuveiros, que sejam sensíveis à sua composição primária. Mais especificamente aqueles determinados pelo detector de superfície, pois há uma estatística de chuveiros detectados significativamente maior. Damos especial atenção às flutuações intrínsecas – chuveiro-a-chuveiro – do parâmetro de inclinação (beta) da Função de Distribuição Lateral, que descreve a variação da densidade de partículas ao longo da direção perpendicular ao eixo do chuveiro, como função da distância a esse eixo. Os resultados indicam que a flutuação intrínseca em beta, para eventos inclinados (45-60 graus) com E maior que 1018.5 eV, possui uma tendência de diminuição com a energia até valores em torno de 1019.8 eV. Este resultado é consistente com o encontrado anteriormente em análises de composição química sobre a evolução com a energia da profundidade de máximo (Xmax) dos chuveiros atmosféricos extensosmedida pelos detectores do Auger em modo híbrido, em que em energias acima de 1018.5 eV, observase que os chuveiros tendem a atingir seu máximo numa região mais bem definida da atmosfera, levando, por conseguinte, a flutuações menores no sinal no solo.
The Pierre Auger Observatory is an ultra high energy cosmic ray detector (E more than or equal as 1018 eV) which has hybrid characteristics combining surface and fluorescence detectors. Determining the cosmic rays chemical composition is one of its most important challenges. There are evidences that cosmic ray primaries with energy above 1018.5 eV are heavy and this conclusion is based on recent results on the evolution of extensive air showers (cascades of particles formed by the collision of primary cosmic rays in the top of the atmosphere with nitrogen and oxygen molecules). Therefore, it is mandatory to find additional parameters supporting that conclusion. In this thesis, the evolution with energy of parameters characterizing the shower and with sensitivity to chemical composition are studied. More specifically, parameters determined by the surface detector are analyzed due to the high statistics in this operation mode. Special attention is given to the instrinsic - shower to shower - fluctuations of the slope parameter (beta) of the Lateral Distribution Function which describes the particles density variation in the plane perpendicular to the shower axis as a function of distance to that axis. The results show that the intrinsic fluctuation of Beta, for inclined showers (45-60 degrees) with energy above 1018.5 eV, where the detector resolution is small compared to the total fluctuation, has a trend to decrease with energy up to 1019.6 eV. This result is consistent with recent results on the energy evolution of the depth of shower maxima (Xmax) of extensive air showers, where above 1018.5 eV, the distributions of Xmax show less fluctuations, leading, in turn, to less fluctuations on the ground level.
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Morejon, Leonel [Verfasser]. "New Interaction Models of Ultra-high-energy Cosmic Rays from a Nuclear Physics Approach / Leonel Morejon." Berlin : Humboldt-Universität zu Berlin, 2021. http://d-nb.info/1230406751/34.
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Schulz, Alexander [Verfasser], and J. [Akademischer Betreuer] Blümer. "Measurement of the Energy Spectrum and Mass Composition of Ultra-high Energy Cosmic Rays / Alexander Schulz. Betreuer: J. Blümer." Karlsruhe : KIT-Bibliothek, 2016. http://d-nb.info/1095665456/34.
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Schüssler, Fabian. "Measurement of the Energy Spectrum of Ultra-High Energy Cosmic Rays using Hybrid Data of the Pierre Auger Observatory." [S.l. : s.n.], 2008. http://digbib.ubka.uni-karlsruhe.de/volltexte/1000009955.
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Schüssler, Fabian. "Measurement of the energy spectrum of ultra-high energy cosmic rays using hybrid data of the Pierre Auger Observatory." Karlsruhe Forschungszentrum Karlsruhe, 2009. http://d-nb.info/995867089/34.
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Nierstenhoefer, Nils [Verfasser]. "On the Origin and Propagation of Ultra-High Energy Cosmic Rays (Measurements & Prediction Techniques) / Nils Nierstenhoefer." Wuppertal : Universitätsbibliothek Wuppertal, 2011. http://d-nb.info/101622592X/34.
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Louedec, Karim. "Atmospheric aerosols at the Pierre Auger Observatory : characterization and effect on the energy estimation for ultra-high energy cosmic rays." Phd thesis, Université Paris Sud - Paris XI, 2011. http://tel.archives-ouvertes.fr/tel-00647476.
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Les aérosols atmosphériques à l'Observatoire Pierre Auger : caractérisation et effet sur l'estimation de l'énergie des rayons cosmiques d'ultra-haute énergie.L'Observatoire Pierre Auger, situé dans la province de Mendoza en Argentine, réalise actuellement de grandes avancées dans la connaissance de la nature et de l'origine des rayons cosmiques d'ultra-haute énergie. Utilisant une technique de détection hybride, basée sur des détecteurs de surface et des télescopes de fluorescence, il fournit une large statistique, une bonne résolution en énergie, et un contrôle solide des incertitudes systématiques.L'un des principaux défis pour la technique de détection par fluorescence est la compréhension de l'atmosphère, utilisée comme un calorimètre géant. Afin de réduire autant que possible les incertitudes systématiques sur les mesures par fluorescence, la Collaboration Auger a développé un important programme de suivi de l'atmosphère. Le but de ce travail est d'améliorer notre compréhension sur les aérosols atmosphériques, ainsi que leur effet sur la propagation de la lumière de fluorescence.En utilisant un modèle de rétrotrajectographie des masses d'air, il a été montré que les nuits pauvres en aérosols ont des masses d'air provenant plus directement de l'Océan Pacifique. Pour la première fois, l'effet de la taille des aérosols sur la propagation de la lumière a été estimé. En effet, selon l'approche Ramsauer, les gros aérosols ont le plus grand effet sur la diffusion de la lumière. Ainsi, la dépendance en taille a été ajoutée aux paramétrisations décrivant la diffusion de la lumière et utilisée par la Collaboration Auger. Une surestimation systématique de l'énergie et du maximum de développement de la gerbe Xmax est observé.Enfin, une méthode basée sur les tirs laser très incliné produit par le laser central d'Auger a été développée pour estimer la taille des aérosols. Des tailles d'aérosols jusque là jamais détectées à l'Observatoire Pierre Auger peuvent à présent être contraintes. De premiers résultats montrent une population d'aérosols de grande taille en utilisant des tirs laser effectués dans le passé.
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Weidenhaupt, Klaus Frank [Verfasser]. "Antenna calibration and energy measurement of ultra-high energy cosmic rays with the Auger Engineering Radio Array / Klaus Frank Weidenhaupt." Aachen : Hochschulbibliothek der Rheinisch-Westfälischen Technischen Hochschule Aachen, 2014. http://d-nb.info/1065959966/34.
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Schmidt, David [Verfasser], J. [Akademischer Betreuer] Blümer, and A. [Akademischer Betreuer] Etchegoyen. "Sensitivity of AugerPrime to the masses of ultra-high-energy cosmic rays / David Schmidt ; J. Blümer, A. Etchegoyen." Karlsruhe : KIT-Bibliothek, 2019. http://d-nb.info/1184990115/34.
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Maurel, Detlef [Verfasser], and J. [Akademischer Betreuer] Blümer. "Mass composition of ultra-high energy cosmic rays based on air shower universality / Detlef Maurel. Betreuer: J. Blümer." Karlsruhe : KIT-Bibliothek, 2013. http://d-nb.info/1044956178/34.
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Griffith, Nathan E. "Microwave Detection of Cosmic Rays and Multi-Messenger Analysis of the Parameters of Ultra-High Energy Astrophysical Sources." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1429799044.
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Stapleton, James C. "Ultra-High Energy Cosmic Rays: Composition, Early Air Shower Interactions, and Xmax Skewness." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1431044195.
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Blanco, Otano Miguel. "Different approaches to determine the composition of the ultra-high energy cosmic rays in the Pierre Auger Observatory." Thesis, Paris 6, 2014. http://www.theses.fr/2014PA066643/document.
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L’objectif de cette thèse est d’améliorer la détermination de la masse des rayons cosmiques d’ultra haute énergie faite à l’Observatoire Pierre Auger. Aujourd’hui cette mesure est faite à travers l’utilisation de télescopes à fluorescence qui nécessitent des conditions de luminosité spéciales réduisantle cycle utile à environ 10%. Trois approches différentes sont proposées:La première approche est une nouvelle analyse. Les muons issus des gerbes horizontales sont déviés par le champ magnétique terrestre. Cette déviation modifie l’empreinte au sol des gerbes atmosphériques et est fonction de la longueur de parcours des muons. Un estimateur de Xμmax, leur point de productionmaximum, qui dépend de la masse du primaire peut être construit.La deuxième approche explore la détection du rayonnement radio émis par les gerbes atmosphériques, une technique similaire à la fluorescence mais sans limitation du cycle utile. La détection du rayonnement de Bremsstrahlung moléculaire est revue et explorée de différentes manières.La troisième approche propose un nouveau type de détecteur pour le réseau de surface, ces détecteurs ayant une réponse distincte aux différentes composantes des gerbes atmosphériques : électromagnétique et muonique. La mesure de la composante muonique est aussi un moyen d’accéder à la nature du primaire.La nouvelle analyse semble un outil prometteur qui peut s’appliquer à tout lot de données. La radio-détection en revanche n’apparaît pas comme une alternative compétitive face aux techniques traditionnelles. Le nouveau détecteur offre de belles perspectives et devrait être considéré pour l'équipementdes futurs observatoiresThe motivation of this PhD thesis is to improve the capabilities to determine the mass composition of the ultra-high energy cosmic rays in the Pierre Auger Observatory. The measure of their mass composition is done with the fluorescence technique, that needs special luminosity conditions that reduce the exposure time to about 10% of the time. Three different approaches are proposed.The first approach is a new analysis. Muons in the horizontal showers are deviated by the magnetic field of the Earth. This deflection is related with different characteristics of the extensive air shower that allow the construction of an estimator to obtain an alternative measure of Xμmax, an observable sensitive to the mass of the primary.The second approach is to explore the detection of the radio emission produced in the extensive air showers, a technique similar to the fluorescente one, but without the limitations in the duty cycle. The detection of the Molecular Bremsstrahlung Radiation emission is revised and investigated from different points of view.The third approach is to propose a new surface detector that obtains different responses to the different components of the extensive air shower: electromagnetic and muonic. The access to the muonic component is another way to access to the composition of the primary particle.The new method of analysis proposed appears as a promising tool to be applied in any data set. The technique of the radio detection did not show clear indications of being an alternative to traditional techniques. The new detector represents a promising alternative to be considered in any future ultra-high energy cosmic rays experiment
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De, Domenico Manlio. "Propagation of Ultra-High Energy Cosmic Rays and anisotropy studies with the Pierre Auger Observatory: the multiscale approach." Doctoral thesis, Università di Catania, 2012. http://hdl.handle.net/10761/992.
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The main goal of this thesis is the investigation of the arrival directions of ultra-high energy cosmic rays (UHECRs). The clustering of such events, collected by the Pierre Auger Observatory, is used to infer the nature of sources and their density, as well as other physical unknowns. Results are based on the comparison between real and simulated data. Hence, an ad hoc Monte Carlo code (HERMES) for the realistic simulation of UHECR propagation in the Universe and a novel method (MAF) to quantify the amount of clustering in a data set of few UHECR events have been developed.
In the first chapter, a general overview of UHECR physics is given, with particular attention to the Auger Observatory and the most recent results regarding its measurements.
In the second and third chapters, we present the general structure of HERMES and we discuss the procedures adopted to simulate the propagation of UHECRs in a magnetized Universe. In the second chapter, magnetic fields are treated, and their impact on the propagation of UHECRs is discussed. In particular, we simulate the diffusion of charged particles in both turbulent and structured magnetic fields for energy values ranging from 10^17 to 10^21 eV. In the third chapter, the propagation of protons and heavier nuclei is treated. We define the cosmological framework of HERMES and we parameterize the cosmic background radiation (CBR). The parameterizations for the cross section of the interactions between nuclei and CBR photons are discussed, as well as the relevant energy-loss processes. The impact of propagation on the GZK horizon of UHE protons is investigated, and comparisons between our results and the literature those obtained with other simulators are presented.
In the fourth chapter, a novel method is introduced to estimate the statistical significance of clustering in the arrival direction distribution of few events, a necessary requirement because of the current small number of events observed above 5x10^19 eV. The method involves a multiscale procedure, based on information theory and extreme value statistics, providing high discrimination power, even in presence of strong background isotropic contamination. It is extended to allow correlation analysis with catalogues of sources. Here, the term "multiscale" explicitly indicates the dependence on the angular scale adopted to investigate the arrival directions of UHECRs. It is shown that MAF has some valuable features, it is: i) semi-analytical, ii) very sensitive to small, medium and large scale clustering, iii) not biased against the null hypothesis.
Finally, in the fifth, sixth and seventh chapters, Monte Carlo simulations are extensively adopted to investigate real data. In the fifth chapter we use multiscale methods to explore the effects of experimental uncertainties on clustering and correlation of UHECRs with catalogues. In the sixth chapter, energy losses due to secondary particle production or photo-disintegration, as well as deflections due to galactic (GMF) and extragalactic magnetic fields (EMF), are taken into account. All of such interactions, together with the distribution of sources, produce different arrival directions of events at Earth. Hence, clustering in events detected with the Auger Observatory and in simulated sky maps of UHECRs, mimicking realistic astrophysical scenarios, is used to put bounds on some relevant unknowns, as the fraction of protons in the data, the density of sources and the strength of the turbulent component of the EMF. Moreover, the possibility that nearby active galactic nuclei and black holes could be responsible for the observed flux of UHECRs is explored in detail. In the seventh chapter, we perform a more extended study which takes into account additional observables, as the elongation rate and the energy spectrum. By varying the underlying assumptions, we have outlined an astrophysical scenario able to explain Auger data from a phenomenological point of view.
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Schüssler, Fabian [Verfasser]. "Measurement of the energy spectrum of ultra-high energy cosmic rays using hybrid data of the Pierre Auger Observatory / Fabian Schüssler." Karlsruhe : Forschungszentrum Karlsruhe, 2009. http://d-nb.info/995867089/34.
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Vliet, Arjen René /van [Verfasser], and Günter [Akademischer Betreuer] Sigl. "Propagation of ultra-high-energy cosmic rays and their secondaries with CRPropa / Arjen René van Vliet. Betreuer: Günter Sigl." Hamburg : Staats- und Universitätsbibliothek Hamburg, 2015. http://d-nb.info/1071948229/34.
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Bridgeman, Ariel [Verfasser], and J. [Akademischer Betreuer] Blümer. "Determining the Mass Composition of Ultra-high Energy Cosmic Rays Using Air Shower Universality / Ariel Bridgeman ; Betreuer: J. Blümer." Karlsruhe : KIT-Bibliothek, 2018. http://d-nb.info/1166234266/34.
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König, Hampus. "Evaluation of detector Mini-EUSO to study Ultra High-Energy Cosmic Rays and Ultra Violet light emissions observing from the International Space Station." Thesis, Luleå tekniska universitet, Institutionen för system- och rymdteknik, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-72552.
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Under the name EUSO, or Extreme Universe Space Observatory, are multiple instruments where some are currently under design or construction and others have concluded their mission. The main goal they have in common is to detect and analyse cosmic rays with very high energies by using the Earth's atmosphere as a detector. One instrument is called Mini-EUSO, will be placed on the international space station during 2019, and its engineering model is currently being used to collect data and test the function of different components. The engineering model differ from the full scale instrument, and it is also possible to use it for other purposes as well. In this thesis, some of the collected data is used to analyse and compare the engineering models specification to the full Mini-EUSO instrument, with focus on field of view, inert areas on the sensor and its general function. Objects, such as stars, meteors and satellites were also detected, and used in the tests. In addition a short test regarding the possibility to use the instrument to detect plastic residing in the ocean is made, by utilizing fluorescent properties of the plastics. The thesis came to the conclusion that some adjustments needed to be made on the engineering model, but also that the specifications of it was within expected ranges. Several of the objects found can also be used to improve detection algorithms. In addition, the preliminary tests regarding plastic detection in the ocean, have positive results.
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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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Rodrigues, Xavier [Verfasser], Walter [Gutachter] Winter, Anna [Gutachter] Franckowiak, and Markus [Gutachter] Böttcher. "Blazars as Sources of Neutrinos and Ultra-high-energy Cosmic Rays / Xavier Rodrigues ; Gutachter: Walter Winter, Anna Franckowiak, Markus Böttcher." Berlin : Humboldt-Universität zu Berlin, 2019. http://d-nb.info/1198207140/34.
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Lyberis, Haris. "Study of the ultra-high energy cosmic rays with the Pierre Auger Observatory : towards observations of anisotropies in arrival directions ?" Paris 7, 2011. http://www.theses.fr/2011PA077099.
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Cette thèse concerne l'étude des anisotropies des rayons cosmiques d'ultra-haute énergie observé à l'aide de l'Observatoire Pierre Auger. Une partie de recherche et développement a été effectué afin d'augmenter la gamme dynamique des PM Hamamatsu en s'appuyant sur l'extraction du signal de dy-nodes plus profonde, permettant d'atteindre les 20 bits. Pour augmenter la statistique à haute énergie, un trigger plus lâche pour les prochaines étude des données d'Auger a été développé. De plus, des re¬cherche de sources ponctuelles en direction du centre galactique et de Centaurus ont été menées. Une nouvelle méthode pour la recherche d'anisotropies sans comparaison avec un catalogue a été dévelop¬pée, fournissant le degré de regroupement et un moyen analytique pour calculer la probabilité pénali-| sée. Grâce a celle-ci, d'importantes limites sur la densité de source et les déflexions des rayons cosmi¬ques extra-galactiques ont pu être posées. Dans la gamme d'énergie plus faible, une analyse de la première harmonique a été mené avec l'aide d'une nouvelle méthode tenant compte des effets de dé¬tection. Des limites supérieures au delà de 1 EeV ont été posées avec de surcroît une indication pour une réelle anisotropie indiquée par la présence d'une transition régulière dans sa phase. En utilisant une méthode numérique pour résoudre l'équation de diffusion dans un champ magnétique galactique simpli¬fié et des simulations Monte Carlo, nous avons comparé le degré d'anisotropie induit avec celui possible avec la possibilité de relâcher certaines hypothèses (source stationnaires, émission isotrope)This thesis concerns the study anisotropies of UHECRs observed by the Pierre Auger Observatory. R&D was done to increase of the dynamical range of Hamamatsu PMTs using the technique based on the reading out of deeper dynodes, reaching 20 bits. To increase the statistics at high energy, a relax trigger selection was designed to be used in further Auger data analysis. Further, point sources were searched in direction of the Galactic Center and Centaurus A. We also developed a new method for searching for anisotropies without relying on any catalog that provides the clustering scale and an analytical way to compute the chance probability. Using it, we place important limits on the density of sources and the deflections of the extra-galactic cosmic rays. In the low energy range, we performed a first harmonic analysis using a new method to account for detector effects. Upper bounds were given above 1 EeV with an indication of a signal at all energies pointed out by the smooth transition of the phase. Finally, using both a numerical method to solve the diffusion equation in a simplified galactic magnetic field mo-del and Monte Carlo simulations, we compare the resulting anisotropy with the possible one, studying also relaxing some hypothesis (stationary sources, isotropic emission)
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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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Lauscher, Markus Verfasser], Thomas [Akademischer Betreuer] Hebbeker, and Christopher Henrik V. [Akademischer Betreuer] [Wiebusch. "Search for the sources of ultra-high energy cosmic rays with the Pierre Auger Observatory / Markus Lauscher ; Thomas Hebbeker, Christopher Wiebusch." Aachen : Universitätsbibliothek der RWTH Aachen, 2016. http://d-nb.info/1156922259/34.
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Halliday, Robert Paul. "Electronics and Timing for the AugerPrime Upgrade and Correlation of Starburst Galaxies with Arrival Directions of Ultra High Energy Cosmic Rays." Case Western Reserve University School of Graduate Studies / OhioLINK, 2019. http://rave.ohiolink.edu/etdc/view?acc_num=case1553599216169462.
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Lauscher, Markus [Verfasser], Thomas Akademischer Betreuer] Hebbeker, and Christopher Henrik V. [Akademischer Betreuer] [Wiebusch. "Search for the sources of ultra-high energy cosmic rays with the Pierre Auger Observatory / Markus Lauscher ; Thomas Hebbeker, Christopher Wiebusch." Aachen : Universitätsbibliothek der RWTH Aachen, 2016. http://d-nb.info/1156922259/34.
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Fenu, Francesco [Verfasser], and Andrea [Akademischer Betreuer] Santangelo. "A Simulation Study of the JEM-EUSO Mission for the Detection of Ultra-High Energy Cosmic Rays / Francesco Fenu ; Betreuer: Andrea Santangelo." Tübingen : Universitätsbibliothek Tübingen, 2013. http://d-nb.info/1162896736/34.
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Collica, L. "MASS COMPOSITION STUDIES OF ULTRA HIGH ENERGY COSMIC RAYS THROUGH THE MEASUREMENT OF THE MUON PRODUCTION DEPTHS AT THE PIERRE AUGER OBSERVATORY." Doctoral thesis, Università degli Studi di Milano, 2014. http://hdl.handle.net/2434/252009.
Full textAbstract:
The Pierre Auger Observatory in Argentina studies Ultra High Energy Cosmic Rays (UHECRs) physics. The flux of CRs at these energies (above 1 EeV) is very low and UHECRs properties must be inferred from the measurements of the Extensive Air Showers (EAS) that the cosmic ray primary produces in the atmosphere.
Two complementary techniques are used at Auger to detect EAS: a surface detector (SD) array of water Cherenkov tanks, which sample particle at ground level, and fluorescence detectors (FD), which collect the UV light emitted by the de-excitation of nitrogen nuclei in the atmosphere, and can operate only in clear, moonless nights. Auger is the largest cosmic rays detector ever built and it provides high- quality data together with unprecedented statistics.
The main goal of this thesis is the measurement of UHECRs mass composition using data from Auger SD. Measuring the cosmic ray composition at the highest energies is of fundamental importance from Mass Composition Studies of Ultra High the astrophysical point of view, since it could discriminate between different scenarios of origin and propagation of cosmic rays. Moreover, mass composition studies are of utmost importance for particle physics. As a matter of fact, knowing the composition helps in exploring the hadronic interactions at ultra-high energies, inaccessible to present accelerator experiments.
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Zimmermann, Benedikt Hermann [Verfasser], and M. [Akademischer Betreuer] Weber. "Radio-detection of ultra-high energy cosmic rays: multi-channel data acquisition and combined analysis of timing and energy information / Benedikt Hermann Zimmermann ; Betreuer: M. Weber." Karlsruhe : KIT-Bibliothek, 2017. http://d-nb.info/1143026993/34.
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Heinze, Jonas. "Ultra-high-energy cosmic-ray nuclei and neutrinos in models of gamma-ray bursts and extragalactic propagation." Doctoral thesis, Humboldt-Universität zu Berlin, 2020. http://dx.doi.org/10.18452/21386.
Full textAbstract:
Utrahochenergetische kosmische Strahlung (ultra-high-energy cosmic rays -- UHECR) besteht aus ionisierten Atomkernen mit den höchsten Teilchenergien, die je gemessen wurden.
Zwar wurden die Quellen von UHECRs noch nicht eindeutig identifiziert, doch gibt es deutliche Anzeichen, dass sie extragalaktisch sind.
Um die Beobachtungen zu interpretieren, wird ein Modell der Wechselwirkungen mit Photofeldern sowohl in der Quelle als auch während der extragalaktischen Propagation benötigt.
Bei diesen Wechselwirkungen werden sekundäre Neutrinos erzeugt.
Diese Dissertation behandelt Modelle der Quellen von UHECRs und die damit verbundene Produktion von Neutrinos sowohl in den Quellen als auch während der Propagation.
Dafür wurde ein neuer Code, PriNCe, für die Propagation von UHECRs entwickelt. Dieser Code wird in einem umfangreichen Parameterscan für ein generisches Quellenmodell angewendet, welches mit dem Spektralindex, der maximalen Rigidität, der kosmologischen Quellenverteilung und der chemischen Komposition als freie Parameter definiert ist. Dabei wird der Einfluss von verschiedenen Photodisintegrations- und Luftschauermodellen auf die erwarteten Eigenschaften der Quellen demonstriert.
Der Fluss kosmogenischer Neutrinos, der sich daraus robust vorhersagen lässt, liegt außerhalb der Reichweite aller derzeit geplanten Neutrinodetektoren.
GRBs als mögliche Quellen von UHECRs werden im Multi-Collision Internal-Shock Modell simuliert, welches die Abhängigkeit der Strahlungsprozesse von den verschiedenen Dissipationsradien im Plasmajet berücksichtigt.
Für dieses Modell wird der Effekt demonstriert, den verschiedene Annahmen über die anfängliche Verteilung des Plasmajets und das hydrodynamische Modell auf die resultierende UHECR- und Neutrinosstrahlung haben.
Für den Gammastrahlenblitz GRB170817A, welcher zusammen mit einem Gravitationswellensignal beobachtet wurde, werden Vorhersagen für den Neutrinofluss und ihre Abhängigkeit vom Beobachtungswinkel gemacht.Ultra-high-energy cosmic rays (UHECRs) are the most energetic particles observed in the Universe. While the astrophysical sources of UHECRs have not yet been uniquely identified, there are strong indications for an extragalactic origin. The interpretation of the observations requires both simulations of UHECR acceleration and energy losses inside the source environment as well as interactions during extragalactic propagation. Due to their extreme energies, UHECR will interact with photons in these environments, producing a flux of secondary neutrinos. This dissertation deals with models of UHECR sources and the accompanying neutrino production in the source environment and during extragalactic propagation. We have developed a new, computationally efficient code, PriNCe, for the extragalactic propagation of UHECR nuclei. The PriNCe code is applied for an extensive parameter scan of a generic source model that is described by the spectral index, the maximal rigidity, the cosmological source evolution and the injected mass composition. In this scan, we demonstrate the impact of different disintegration and air-shower models on the inferred source properties. A prediction for the expected flux of cosmogenic neutrinos is also derived. GRBs are discussed as specific UHECR source candidates in the multi-collision internal-shock model. This model takes the radiation from different radii in the GRB outflow into account. We demonstrate how different assumptions about the initial setup of the jet and the hydrodynamic collision model impact the production of UHECRs and neutrinos. Motivated by the multi-messenger observation of GRB170817A, we discuss the expected neutrino production from this GRB and its dependence on the observation angle. We show that the neutrino flux for this event is at least four orders of magnitude below the detection limit for different geometries of the plasma jet.