Download or read book Observation of a Large scale Anisotropy in the Arrival Directions of Cosmic Rays Above 8imes10 18 EV written by and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Large Scale Distribution of Arrival Directions of Cosmic Rays Detected Above 10 EV at the Pierre Auger Observatory written by and published by . This book was released on 2012 with total page 20 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Observations of Large Scale Sidereal Anisotropy in 1 and 11 TeV Cosmic Rays from the MINOS Experiment written by and published by . This book was released on 2012 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The MINOS Near and Far Detectors are two large, functionally-identical, steel-scintillating sampling calorimeters located at depths of 220 mwe and 2100 mwe respectively. The detectors observe the muon component of hadronic showers produced from cosmic ray interactions with nuclei in the earth's atmosphere. From the arrival direction of these muons, the anisotropy in arrival direction of the cosmic ray primaries can be determined. The MINOS Near and Far Detector have observed anisotropy on the order of 0.1% at 1 and 11 TeV respectively. The amplitude and phase of the first harmonic at 1 TeV are 8.2 ± 1.7(stat.) x 10−4 and (8.9 ± 12.1(stat.)){sup o}, and at 11 TeV are 3.8 ± 0.5(stat.) x 10−4 and (27.2 ± 7.2(stat.)){sup o}.

Download or read book Anisotropy and Chemical Composition of Ultra high Energy Cosmic Rays Using Arrival Directions Measured by the Pierre Auger Observatory written by and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Pierre Auger Collaboration has reported evidence for anisotropy in the distribution of arrival directions of the cosmic rays with energies E> E{sub th} = 5.5 x 1019 eV. These show a correlation with the distribution of nearby extragalactic objects, including an apparent excess around the direction of Centaurus A. If the particles responsible for these excesses at E> E{sub th} are heavy nuclei with charge Z, the proton component of the sources should lead to excesses in the same regions at energies E/Z. We here report the lack of anisotropies in these directions at energies above E{sub th}/Z (for illustrative values of Z = 6,13,26). If the anisotropies above E{sub th} are due to nuclei with charge Z, and under reasonable assumptions about the acceleration process, these observations imply stringent constraints on the allowed proton fraction at the lower energies.

Download or read book Coverage and large scale anisotropies estimation methods for the Pierre Auger Observatory written by J. Ch Hamilton and published by . This book was released on 2005 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: When searching for anisotropies in the arrival directions of Ultra High Energy Cosmic Rays, one must estimate the number of events expected in each direction of the sky in the case of a perfect isotropy. We present in this article a new method, developed for the Auger Observatory, based on a smooth estimate of the zenith angle distribution obtained from the data itself (which is essentially unchanged in the case of the presence of a large scale anisotropy pattern). We also study the sensitivity of several methods to detect large-scale anisotropies in the cosmic ray arrival direction distribution : Rayleigh analysis, dipole fitting and angular power spectrum estimation.

Download or read book Cosmic Ray Air Shower Measurement from Space written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-08-17 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: A feasibility study has been initiated to observe from space the highest energy cosmic rays above 1021 eV. A satellite observatory concept, the Maximum-energy Auger (Air)-Shower Satellite (MASS), is recently renamed as the Orbital Wide-angle Collector (OWL) by taking its unique feature of using a very wide field-of-view (FOV) optics. A huge array of imaging devices (about 10(exp 6) pixels) is required to detect and record fluorescent light profiles of cosmic ray cascades in the atmosphere. The FOV of MASS could extend to as large as about 60 in. diameter, which views (500 - 1000 km) of earth's surface and more than 300 - 1000 cosmic ray events per year could be observed above 1020 eV. From far above the atmosphere, the MASS/OWL satellite should be capable of observing events at all angles including near horizontal tracks, and would have considerable aperture for high energy photon and neutrino observation. With a large aperture and the spatial and temporal resolution, MASS could determine the energy spectrum, the mass composition, and arrival anisotropy of cosmic rays from 1020 eV to 1022 eV; a region hitherto not explored by ground-based detectors such as the Fly's Eye and air-shower arrays. MASS/OWL's ability to identify cosmic neutrinos and gamma rays may help providing evidence for the theory which attributes the above cut-off cosmic ray flux to the decay of topological defects. Very wide FOV optics system of MASS/OWL with a large array of imaging devices is applicable to observe other atmospheric phenomena including upper atmospheric lightning. The wide FOV MASS optics being developed can also improve ground-based gamma-ray observatories by allowing simultaneous observation of many gamma ray sources located at different constellations. Takahashi, Yoshiyuki Marshall Space Flight Center NASA-CR-204041, NAS 1.26:204041 NAS8-38609; NCC8-65...

Download or read book Update on the Correlation of the Highest Energy Cosmic Rays with Nearby Extragalactic Matter written by and published by . This book was released on 2010 with total page 33 pages. Available in PDF, EPUB and Kindle. Book excerpt: Data collected by the Pierre Auger Observatory through 31 August 2007 showed evidence for anisotropy in the arrival directions of cosmic rays above the Greisen-Zatsepin-Kuzmin energy threshold, 6 x 1019 eV. The anisotropy was measured by the fraction of arrival directions that are less than 3.1{sup o} from the position of an active galactic nucleus within 75 Mpc (using the Veron-Cetty and Veron 12th catalog). An updated measurement of this fraction is reported here using the arrival directions of cosmic rays recorded above the same energy threshold through 31 December 2009. The number of arrival directions has increased from 27 to 69, allowing a more precise measurement. The correlating fraction is (386{sup +7})%, compared with 21% expected for isotropic cosmic rays. This is down from the early estimate of (6913{sup +11})%. The enlarged set of arrival directions is examined also in relation to other populations of nearby extragalactic objects: galaxies in the 2 Microns All Sky Survey and active galactic nuclei detected in hard X-rays by the Swift Burst Alert Telescope. A celestial region around the position of the radiogalaxy Cen A has the largest excess of arrival directions relative to isotropic expectations. The 2-point autocorrelation function is shown for the enlarged set of arrival directions and compared to the isotropic expectation.

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 On the Possible Association of Ultra High Energy Cosmic Rays with Nearby Active Galaxies written by and published by . This book was released on 2008 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt: Data collected by the Pierre Auger Observatory provide evidence for anisotropy in the arrival directions of cosmic rays (CRs) with energies>57 EeV that suggests a correlation with the positions of active galactic nuclei (AGN) located within H"5 Mpc. However, this analysis does not take into account AGN morphology. A detailed study of the sample of AGN whose positions correlate with the CR events shows that most of them are classified as Seyfert 2 and low-ionization nuclear emission-line region (LINER) galaxies which do not differ from other local AGN of the same types. Therefore, the claimed correlation between the CR events observed by the Pierre Auger Observatory and local active galaxies should be considered as resulting from a chance coincidence, if the production of the highest energy CRs is not episodic in nature, but operates in a single object on long (e"Myr) timescales. Additionally, most of the selected sources do not show significant jet activity, and hence--in the framework of the jet paradigm--there are no reasons for expecting them to accelerate CRs up to the highest energies, H"02° eV, at all. If the extragalactic magnetic fields and the sources of these CRs are coupled with matter, it is possible that the deflection angle is larger than expected in the case of a uniform source distribution due to effectively larger fields. A future analysis has to take into account AGN morphology and may yield a correlation with a larger deflection angle and/or more distant sources. We further argue that Cen A alone could be associated with at least 4 events due to its large radio extent, and Cen B can be associated with more than 1 event due to its proximity to the Galactic plane and, correspondingly, the stronger Galactic magnetic field the ultra high energy CRs (UHECRs) encounter during propagation. If the UHECRs associated with these events are indeed accelerated by Cen A and Cen B, their deflection angles may provide information on the structure of the magnetic field in the direction of these putative sources. Future -ray observations (by, e.g., Gamma-Ray Large Area Space Telescope [GLAST], High Energy Stereoscopic System [HESS]) may provide additional clues to the nature of the accelerators of the UHECRs in the local Universe.

Download or read book The Early Universe and the Cosmic Microwave Background Theory and Observations written by Norma G. Sànchez and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 583 pages. Available in PDF, EPUB and Kindle. Book excerpt: The goal of the Daniel Chalonge School on Astrofundamental Physics is to contribute to a theory of the universe (and particularly of the early universe) up to the marks, and at the scientific height of, the unprecedented accuracy, existent and expected, in the observational data. The impressive development of modern cosmology during the last decades is to a large extent due to its unification with elementary particle physics and quantum field theory. The cross-section between these fields has been increasing setting up Astrofundamental Physics. The early universe is an exceptional (theoretical and experimental) laboratory in this new discipline. This NATO Advanced Study Institute provided an up dated understanding, from a fundamental physics and deep point of view, of the progress and key issues in the early universe and the cosmic microwave background: theory and observations. The genuine interplay with large scale structure formation and dark matter problem were discussed. The central focus was placed on the cosmic microwave background. Emphasis was given to the precise inter-relation between fundamental physics and cosmology in these problems, both at the theoretical and experimental/observational levels, within a deep and well defined programme which provided in addition, a careful interdisciplinarity. Special sessions were devoted to high energy cosmic rays, neutrinos in astrophysics, and high energy astrophysics. Deep understanding, clarification, synthesis, careful interdisciplinarity within a fundamental physics framework, were the main goals of the course.

Download or read book Probing Cosmic Ray Anisotropy with Atmospheric Neutrinos written by Elizabeth J. Wills and published by . This book was released on 2018 with total page 181 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the hundred years that have followed the discovery of cosmic rays, more about them remains unknown than known. Many concerted efforts are currently underway to detect cosmic rays using a variety of detection methods in space, on the surface of Earth, and deep underground. Of the many remaining mysteries, the one addressed in this work is the anisotropy in arrival directions of the cosmic rays incident on the atmosphere. This behaviour has been observed in both hemispheres of the planet, at high significance, from 1 TeV - 1 EeV energy ranges, at angular scales from 5 degrees to 180 degrees, and displays no time variation. It is measured consistently as a 0.1% over- and under-fluctuation. This work presents the first neutrino analysis of cosmic ray arrival directions so far, specifically, in the northern hemisphere. The analysis is done with an atmospheric neutrino dataset which was specifically designed for this analysis and composed of neutrinos detected by the IceCube South Pole Neutrino Observatory from 2011-2016. The goal of the search was to detect cosmic ray anisotropy as observed in atmospheric muons, but this time, in atmospheric neutrinos. To this end, a new atmospheric neutrino dataset was created using machine learning, aiming to increase data acceptance rates by optimizing sacrifices in purity and angular acceptance. The standard analysis techniques were carried out, along with a new log-likelihood method developed to improve sensitivity in a lower-statistics realm. While no signal was detected in this analysis, the analysis methodology has been developed and tested. We project that with a total of twelve years of IceCube data will be required to be sensitive to a dipole anisotropy at the level previously reported by the Tibet-AS[gamma] Collaboration. Detection of cosmic ray anisotropy in the neutrino channel would allow for verification of known cosmic ray shower physics, and particle propagation. The neutrinos could allow us to probe the anisotropy in a new way. If the signal deviates, there could be new physics to discover. The method and data selection are developed, and in several years, new developments will be made towards unraveling the mystery of cosmic ray anisotropy with neutrinos.

Download or read book Patterns in Ultra high Energy Cosmic Ray Arrival Directions written by and published by . This book was released on 2007 with total page 4 pages. Available in PDF, EPUB and Kindle. Book excerpt: The public available data of cosmic ray arrival directions with energies above 4 x 1019 eV present a broad maximum in the cumulative two-point autocorrelation function around 25 degrees. This has been interpreted as the first imprint of the filamentary pattern of large scale structures (LSS) of matter in the near universe. We analyze this suggestion in light of the clustering properties expected from a catalogue of galaxies of the local universe (redshift z (almost equal to)

Download or read book An Attempt to Verify a Reported Anisotropy in the Arrival Directions of Cosmic Rays written by Frank Lee Galeener and published by . This book was released on 1958 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Correlation of the Highest energy Cosmic Rays with the Positions of Nearby Active Galactic Nuclei written by and published by . This book was released on 2007 with total page 33 pages. Available in PDF, EPUB and Kindle. Book excerpt: Data collected by the Pierre Auger Observatory provide evidence for anisotropy in the arrival directions of the cosmic rays with the highest energies, which are correlated with the positions of relatively nearby active galactic nuclei (AGN) [1]. The correlation has maximum significance for cosmic rays with energy greater than (almost equal to) 6 x 1019 eV and AGN at a distance less than (almost equal to) 75 Mpc. We have confirmed the anisotropy at a confidence level of more than 99% through a test with parameters specified a priori, using an independent data set. The observed correlation is compatible with the hypothesis that cosmic rays with the highest energies originate from extra-galactic sources close enough so that their flux is not significantly attenuated by interaction with the cosmic background radiation (the Greisen-Zatsepin-Kuzmin effect). The angular scale of the correlation observed is a few degrees, which suggests a predominantly light composition unless the magnetic fields are very weak outside the thin disk of our galaxy. Our present data do not identify AGN as the sources of cosmic rays unambiguously, and other candidate sources which are distributed as nearby AGN are not ruled out. We discuss the prospect of unequivocal identification of individual sources of the highest-energy cosmic rays within a few years of continued operation of the Pierre Auger Observatory.

Download or read book The ubiquitous mechanism accelerating cosmic rays at all the energies written by Antonio Codino and published by Società Editrice Esculapio. This book was released on 2021-02-04 with total page 297 pages. Available in PDF, EPUB and Kindle. Book excerpt: The mechanism accelerating Cosmic rays in the milky way galaxy and galaxy clusters is identified and described. The acceleration of Cosmic rays is a purely electrostatic process which operate up to the maximum energies of 1023 ev in galaxy clusters. Galactic Cosmic rays are accelerated in a pervasive electrostatic field active in the whole galaxy except in restricted regions shielded by Interstellar and stellar plasma as, for instance, the region occupied by the Solar system. It is proved that the Energy spectrum of the Cosmic radiation in the milky way galaxy, in the region where the Solar system resides, has a constant Spectral index comprised between 2.64-2.68 and the maximum energies of galactic protons are 3.0 × 1019 ev. The agreement of these results with the experimental data is discussed in detail and highlighted. The various physical processes that maintain the stability of the electrostatic structure in the milky way galaxy are the same that generate the galactic magnetic field. Accordingly, the intensity, orientation and direction of the galactic magnetic field are evaluated. The results of the calculation are compared with the observation data, optical and mostly radio astronomi data. The accord of the intensity, orientation and direction of the observed magnetic field with calculation is excellent.

Download or read book Search for Anisotropy in the Arrival Directions of Ultra High Energy Cosmic Rays written by Aka G. Finci and published by . This book was released on 1975 with total page 126 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book The Astrophysics of Galactic Cosmic Rays written by Roland Diehl and published by Springer. This book was released on 2010-12-15 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: R. DIEHL, R. KALLENBACH, E. PARIZOT and R. VON STEIGER / The Astrophysics of Galactic Cosmic Rays 3 I: KEY OBSERVATIONS ON GALACTIC COSMIC RAYS M. E. WIEDENBECK, N. E. YANASAK, A. c. CUMMINGS, AJ. DAVIS, I. S. GEORGE, R. A. LESKE, R. A. MEWALDT, E. C. STONE, P. L. HINK, M. H. ISRAEL, M. LIJOWSKI, E. R. CHRISTIAN and TT VON ROSENVINGE / The Origin of Primary Cosmic Rays: Constraints from ACE Elemental and Isotopic Composition Observations 15 R. A. MEWALDT, N. E. YANASAK, M. E. WIEDENBECK, AJ. DAVIS, w. R. BINNS, E. R. CHRISTIAN, A. C. CUMMINGS, P. L. HINK, R. A. LESKE, S. M. NIEBUR, E. C. STONE and TT VON ROSENVINGE / Radioactive Clocks and Cosmic-Ray Transport in the Galaxy 27 J. J. CONNELL / Cosmic-Ray Composition as Observed by Ulysses 41 R. RAMATY, R. E. LINGENFELTER and B. KOZLOVSKY / Spallogenic Light Elements and Cosmic-Ray Origin 51 E. PARIZOT / Galactic Cosmic Rays and the Light Elements 61 G. MEYNET, M. ARNOULD, G. PAULUS and A. MAEDER / Wolf-Rayet Star Nucleosynthesis and the Isotopic Composition of the Galactic Cosmic Rays 73 S. P. SWORDY / The Energy Spectra and Anisotropies of Cosmic Rays 85 G. TARLE and M. SCHUBNELL / Antiparticles 95 D. MULLER / Cosmic Rays Beyond the Knee 105 II: LESSONS FROM THE HELIOSPHERE G. M. MASON / Heliospheric Lessons for Galactic Cosmic-Ray Acceleration 119 R. A.