Download or read book Features of the Energy Spectrum of Cosmic Rays Above 2 5 times 10 18 EV Using the Pierre Auger Observatory written by Alexander Aab and published by . This book was released on 2020 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Measurement of the Energy Spectrum of Cosmic Rays Above 3 X 1017 EV Using the Infill Array of the Pierre Auger Observatory written by Rivera Bretel Hugo Marcelo and published by . This book was released on 2013 with total page 157 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Pierre Auger Observatory, in Argentina, combines a 3000 $\mathrm{km^2}$ surface array of water Cherenkov detectors with fluorescence telescopes to measure extensive air showers initiated by ultra-high energy cosmic rays. This "hybrid" observatory (in operation since 2004, and completed in 2008) is fully efficient for cosmic rays energies above $10^{18}$ eV, that is, from just below the "ankle" of the energy spectrum up to the highest energies.After the completion of the main observatory, the Auger collaboration has started to deploy new instruments to extend the energy range down to about 0.1 EeV. The planned extensions include two infill surface arrays with 750 and 433 m spacing, with muon detection capabilities, and three additional fluorescence telescopes with a more elevated field of view. The 750 m infill array (covering about 24 $\mathrm{km^2}$) and the new telescopes are now operational. Their aim is the measurement of cosmic rays from below the second knee of the spectrum up to the ankle, where data from the extensions overlap those from the main observatory. The study of the evolutior of the spectrum through the second knee and the ankle, together with the primary mass composition, are crucial to the understanding of the transition from a galactic cosmic ray origin to an extragalactic one.This thesis makes use of data from the 750 m infill array: the objective is the measurement of the cosmic ray energy spectrum in the energy region above $3 \times 10^{17}$ eV, where the array is fully efficient. To get to the energy spectrum, several steps are needed, from the reconstruction of events, through the precise determination of the exposure of the array, up to the determination of the primary energy. The thesis deals with these aspects, before reaching the final result.The first chapter gives a general introduction to cosmic ray physics and detectors. It also summarizes experimental results above the first knee of the spectrum with particular emphasis on those obtained above $10^{17}$ eV. The next two chapters describe the Pierre Auger Observatory and the infill array, respectively. In chapter 2, the main Auger results are summarized too, after a schematic description of th different components of the observatory. Chapter 3 sets the stage for the following chapters. It presents a more detailed description of the characteristics of the infill array, in particular the trigger definitions, event selection and reconstruction. In chapter 4 the performance of the reconstruction of the lateral distribution of observed showers is studied in detail. This is particularly important for the energy spectrum, since the signal at a fixed distance from the shower axis is used as the energy estimator of the event. This signal is estimated by means c the measured lateral distribution of the shower. Chapter 5 presents a comparison between the event reconstruction of the infill and main arrays. Using the set of showers detected by both instruments, the derived geometry and energy estimation are compared, showing a good agreement. In chapter 6, the energy threshold of the array, and hence the set of events to be used, is defined. The methods to obtain the exposure of the array are discussed, as well as related systematic uncertainties. Finally, in chapter 7, the technique to derive the primary energy for each detected shower is presented. The derived energy spectrum is discussed, and the flux is shown to be consistent with that measured by other instruments in the overlapping energy regions.
Download or read book The Cosmic Ray Spectrum at the Highest Energy written by Alessio Gorgi and published by . This book was released on 2009 with total page 119 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Pierre Auger Observatory aims to study the ultra high energy cosmic rays with energies above 1 EeV. To get an accurate measurement of the characteristic of the extensive air showers that the cosmic rays generate in the atmosphere, the Observatory uses a hybrid technique. In this work we have studied the detector performance, including trigger and hardware efficiencies. We have optimized the event selection and estimated the efficiency of the detector acceptance. Uncertainties for event reconstruction were evaluated and propagated to the measured energy spectrum. We have shown that some stations that are not courrently considered part of the event can be included in the event selection procedure. We have studied the effect of loosing the signal of one of the three photomultipliers due to some failure, or the effect of the saturation of the ADC channels or of the photomultiplier to the reconstruction accuracy. The reconstruction uncertainty was also studied in case of ``normal'' events using a method based on fluctuations, to cross-check the results obtained using the fit accuracies. An evaluation of the trigger efficiency was also performed in case one of the three photomultipliers is missing. We have shown that the problems related to the instrumental apparatus only reduce the efficiency where it is not already 100\% and in most of the cases the reconstruction uncertainties are only slightly affected. Furthermore this work gives the first indication that the reconstruction uncertainties of the surface detector data do not change the index of the power law of the measured cosmic rays spectrum.
Download or read book Measurement of the Cosmic Ray Spectrum Above 4 1018 EV Using Inclined Events Detected with the Pierre Auger Observatory written by and published by . This book was released on 2015 with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt: A measurement of the cosmic-ray spectrum for energies exceeding 4×1018 eV is presented, which is based on the analysis of showers with zenith angles greater than 60° detected with the Pierre Auger Observatory between 1 January 2004 and 31 December 2013. The measured spectrum confirms a flux suppression at the highest energies. Above 5.3×1018 eV, the ``ankle'', the flux can be described by a power law E-[gamma] with index [gamma]=2.70 ± 0.02 (stat) ± 0.1 (sys) followed by a smooth suppression region. For the energy (Es) at which the spectral flux has fallen to one-half of its extrapolated value in the absence of suppression, we find Es=(5.12±0.25 (stat)+1.0-1.2 (sys))×1019 eV.
Download or read book Search for Patterns by Combining Cosmic ray Energy and Arrival Directions at the Pierre Auger Observatory written by and published by . This book was released on 2015 with total page 15 pages. Available in PDF, EPUB and Kindle. Book excerpt: Energy-dependent patterns in the arrival directions of cosmic rays are searched for using data of the Pierre Auger Observatory. We investigate local regions around the highest-energy cosmic rays with $E \ge 6 \times 10^$ eV by analyzing cosmic rays with energies above $E \ge 5 \times 10^$ eV arriving within an angular separation of approximately 15$^{\circ }$ . We characterize the energy distributions inside these regions by two independent methods, one searching for angular dependence of energy-energy correlations and one searching for collimation of energy along the local system of principal axes of the energy distribution. No significant patterns are found with this analysis. The comparison of these measurements with astrophysical scenarios can therefore be used to obtain constraints on related model parameters such as strength of cosmic-ray deflection and density of point sources.
Download or read book Measurement of the Cosmic Ray Spectrum Above 4 u00D7 1018 EV Using Inclined Events Detected with the Pierre Auger Observatory written by and published by . This book was released on 2015 with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt: A measurement of the cosmic-ray spectrum for energies exceeding 4×1018 eV is presented, which is based on the analysis of showers with zenith angles greater than 60° detected with the Pierre Auger Observatory between 1 January 2004 and 31 December 2013. The measured spectrum confirms a flux suppression at the highest energies. Above 5.3×1018 eV, the à̀nkle'', the flux can be described by a power law E–? with index ?=2.70 ± 0.02 (stat) ± 0.1 (sys) followed by a smooth suppression region. For the energy (Es) at which the spectral flux has fallen to one-half of its extrapolated value in the absence of suppression, we find Es=(5.12±0.25 (stat)+1.0–1.2 (sys))×1019 eV.
Download or read book Neutrino Physics written by Lars Bergstrm and published by World Scientific. This book was released on 2005 with total page 194 pages. Available in PDF, EPUB and Kindle. Book excerpt: Nobel Symposium 129 on Neutrino Physics was held at Haga Slott in Enkping, Sweden during August 19-24, 2004. Invited to the symposium were around 40 globally leading researchers in the field of neutrino physics, both experimental and theoretical.The dominant theme of the lectures was neutrino oscillations, which after several years were recently verified by results from the Super-Kamiokande detector in Kamioka, Japan and the SNO detector in Sudbury, Canada. Discussion focused especially on effects of neutrino oscillations derived from the presence of matter and the fact that three different neutrinos exist. Since neutrino oscillations imply that neutrinos have mass, this is the first experimental observation that fundamentally deviates from the standard model of particle physics. This is a challenge to both theoretical and experimental physics. The various oscillation parameters will be determined with increased precision in new, specially designed experiments. Theoretical physics is working intensively to insert the knowledge that neutrinos have mass into the theoretical models that describe particle physics. The lectures provided a very good description of the intensive situation in the field right now. The topics discussed also included mass models for neutrinos, neutrinos in extra dimensions as well as the ?seesaw mechanism,? which provides a good description of why neutrino masses are so small.This book is A4 size and in full color.
Download or read book Particles and Fields written by Gilvan A. Alves and published by World Scientific. This book was released on 2002 with total page 675 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Jorge Andr Swieca Summer School is a traditional school in Latin America well known for the high level of its courses and lecturers. This book contains lectures on forefront areas of high energy physics, such as collider physics, neutrino phenomenology, noncommutative field theory, string theory and branes.
Download or read book An Upper Limit to the Photon Fraction in Cosmic Rays Above 10 19 eV from the Pierre Auger Observatory written by and published by . This book was released on 2006 with total page 29 pages. Available in PDF, EPUB and Kindle. Book excerpt: An upper limit of 16% (at 95% c.l.) is derived for the photon fraction in cosmic rays with energies above 1019 eV, based on observations of the depth of shower maximum performed with the hybrid detector of the Pierre Auger Observatory. This is the first such limit on photons obtained by observing the fluorescence light profile of air showers. This upper limit confirms and improves on previous results from the Haverah Park and AGASA surface arrays. Additional data recorded with the Auger surface detectors for a subset of the event sample, support the conclusion that a photon origin of the observed events is not favored.
Download or read book Large Scale Distribution of Ultra High Energy Cosmic Rays Detected at the Pierre Auger Observatory with Zenith Angles Up to 80 written by and published by . This book was released on 2015 with total page 27 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this study, we present the results of an analysis of the large angular scale distribution of the arrival directions of cosmic rays with energy above 4 EeV detected at the Pierre Auger Observatory including for the first time events with zenith angle between 60° and 80°. We perform two Rayleigh analyses, one in the right ascension and one in the azimuth angle distributions, that are sensitive to modulations in right ascension and declination, respectively. The largest departure from isotropy appears in the $E\gt 8$ EeV energy bin, with an amplitude for the first harmonic in right ascension $r_{1}^{\alpha }=(4.4\pm 1.0)\times {{10}^{-2}}$, that has a chance probability $P(\geqslant r_{1}^{\alpha })=6.4\times {{10}^{-5}}$, reinforcing the hint previously reported with vertical events alone.
Download or read book The Energy Spectrum of Cosmic Rays Measured with the HEAT Extension at the Pierre Auger Observatory written by Nils Sven Sebastian Scharf and published by . This book was released on 2013 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Measurement of the Energy Spectrum of Ultra high Energy Cosmic Rays Using Hybrid Data of the Pierre Auger Observatory written by Fabian Schüssler and published by . This book was released on 2009 with total page 136 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cosmic Gamma Rays written by Floyd William Stecker and published by . This book was released on 1971 with total page 262 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cosmic gamma ray production processes, galactic and extragalactic gamma rays, and cosmology.
Download or read book Artificial Neural Networks written by Joao Luis Garcia Rosa and published by BoD – Books on Demand. This book was released on 2016-10-19 with total page 416 pages. Available in PDF, EPUB and Kindle. Book excerpt: The idea of simulating the brain was the goal of many pioneering works in Artificial Intelligence. The brain has been seen as a neural network, or a set of nodes, or neurons, connected by communication lines. Currently, there has been increasing interest in the use of neural network models. This book contains chapters on basic concepts of artificial neural networks, recent connectionist architectures and several successful applications in various fields of knowledge, from assisted speech therapy to remote sensing of hydrological parameters, from fabric defect classification to application in civil engineering. This is a current book on Artificial Neural Networks and Applications, bringing recent advances in the area to the reader interested in this always-evolving machine learning technique.
Download or read book Measuring the Cosmic ray Energy Spectrum Composition and Anisotropy at PeV Scales Using the IceCube Observatory written by James Bourbeau and published by . This book was released on 2019 with total page 141 pages. Available in PDF, EPUB and Kindle. Book excerpt: Since the discovery of cosmic rays over one hundred years ago, many experiments have studied their properties. However, a definitive answer to the questions of where cosmic rays originate and how they are produced is still not known. Over the last several decades, a much more detailed understanding of high energy cosmic rays has begun to materialize. In particular, the cosmic-ray energy spectrum, with its transitions at 3 PeV (the "knee") and 3 EeV (the "ankle"), has been extensively investigated. Based on magnetic confinement arguments, it's generally believed that the energy range between the knee and ankle is where the transition from Galactic to extragalactic sources of cosmic rays. The ability to distinguish between high energy cosmic rays of different composition and study the relative mass abundances of cosmic rays in this transition region can provide invaluable insight in answering the open questions surrounding the origins of cosmic rays. This work focuses on measuring the composition-resolved cosmic-ray energy spectrum at and above the all-particle knee using one year of data collected by the IceCube Observatory. Sepcifically, we focus on making a two mass group spectrum measurement from 10^6.4 GeV to 10^7.8 GeV. The first mass group, referred to as the "light" mass group, is modeled using proton and helium cosmic rays, while the second, "heavy" mass group, is modeled using oxygen and iron cosmic rays. We observe a clear softening of the light spectrum near 3 PeV, while the energy spectrum for the heavy mass group follows a power-law like structure with a spectral index of ~2.7 throughout the entire energy range considered. The observed transition from a primarily light to a heavy-dominant spectrum takes place near 10^7.1 GeV. This feature is characteristic of a potential rigidity-dependent cutoff, or Peters cycle. The change in relative mass abundance could also indicate a possible transition in the source population of cosmic rays. In addition, a study to determine whether or not the light, heavy, or all-particle cosmic-ray energy spectra vary as a function of arrival direction is also presented. This marks the first time an analysis of this kind has been conducted using the IceCube Observatory. No statistically significant spectrum deviations were observed. The results from this analysis can be used to set a limit on the range of possible spectral deviations.
Download or read book Cosmic Ray Physics written by Veronica Bindi and published by CRC Press. This book was released on 2023-03-27 with total page 684 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces you to the physics of cosmic rays, charged particles which reach us from known – and maybe unknown – sources in the cosmos. Starting from a brief history of this fascinating field, it reviews what we know about the creation of elements in the Big Bang and inside stars. It explains cosmic accelerators reaching fabulous energies. It follows the life cycle of cosmic rays all the way from their sources to detection near, on or below Earth. The central three chapters cover what we know about them at the level of the solar system, the Milky Way and the Universe at large. Up-to-date experimental results are presented in detail, showing how they are obtained and interpreted. The book provides an accessible overview of this lively and diversified research field. It will be of interest to undergraduate physics students beginning their studies on astronomy, cosmology, and particle physics. It is also accessible to the general public by concentrating mathematical and technical detail into Focus Boxes. Key features: Complete introductory overview of cosmic ray physics Covers the origins, acceleration, transport mechanisms and detection of these particles Mathematical and technical detail is kept separate from the main text
Download or read book Particle Physics Reference Library written by Stephen Myers and published by Springer Nature. This book was released on 2020-01-01 with total page 867 pages. Available in PDF, EPUB and Kindle. Book excerpt: This third open access volume of the handbook series deals with accelerator physics, design, technology and operations, as well as with beam optics, dynamics and diagnostics. A joint CERN-Springer initiative, the "Particle Physics Reference Library" provides revised and updated contributions based on previously published material in the well-known Landolt-Boernstein series on particle physics, accelerators and detectors (volumes 21A,B1,B2,C), which took stock of the field approximately one decade ago. Central to this new initiative is publication under full open access.
