Download or read book Study of the Performance of the Pierre Auger Observatory and Search for Primary Cosmic Ray Photons written by Viviana Scherini and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Mass Composition Studies of Ultra High Energy Cosmic Rays Through the Measurement of the Muon Production Depths at the Pierre Auger Observatory written by Laura Collica and published by . This book was released on 2014 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Pierre Auger Observatory studies Ultra High Energy Cosmic Rays (UHECRs) physics. The flux of UHECRs is very low (less than 1 particle/km2-year) and their properties must be inferred from the measurements of the secondary particles that the cosmic ray primary produces in the atmosphere. These particles cascades are called Extensive Air Showers (EAS) and can be studied at ground by deploying detectors covering large areas. The EAS physics is complex, and the properties of secondary particles depend strongly on the first interaction, which takes place at an energy beyond the ones reached at accelerators. As a consequence, the analysis of UHECRs is subject to large uncertainties and hence many of their properties, in particular their composition, are still unclear. Two complementary techniques are used at Auger to detect EAS initiated by UHECRs: a 3000 km2 surface detector (SD) array of water Cherenkov tanks which samples particles at ground level and fluorescence detectors (FD) which collect the ultraviolet light emitted by the de-excitation of nitrogen nuclei in the atmosphere, and can operate only in clear, moonless nights. The main goal of this thesis is the measurement of UHECR mass composition using data from the SD of the Pierre Auger Observatory. Measuring the cosmic ray composition at the highe-st energies is of fundamental importance for particle physics and astrophysics. Indeed, it allows to explore the hadronic interactions at ultra-high energies, and to discriminate between different scenarios of origin and propagation of cosmic rays.
Download or read book Studies of the Highest Energy Cosmic Ray Air Showers with the Pierre Auger Observatory Hybrid Dectector written by Bei Cai and published by . This book was released on 2006 with total page 346 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 A complete method to obtain the energy spectrum of inclined cosnic rays detected with the Pierre Auger Observatory written by and published by Univ Santiago de Compostela. This book was released on with total page 163 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Pierre Auger Data Photons and Top down Cosmic Ray Models written by and published by . This book was released on 2006 with total page 8 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Measurement of the Cosmic Ray Flux Above 100 PeV at the Pierre Auger Observatory written by Alan Coleman and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Cosmic rays are particles and nuclei that arrive at Earth and act as messengers, informing us of the nature of celestial objects and events throughout the universe. Some of the highest energy events, with over a Joule of energy, are more energetic than what can be made on Earth in modern particle accelerators. In the ultra-highenergy range > 100 PeV, the arrival rate is low enough (1 per km 2 per year, or less) that there are still many outstanding questions concerning their origin and what types of particles they are. Further, their rarity presents an experimental challenge as direct detection of cosmic rays above this energy would require decades to centuries of data collection. Instead, the particles cascades created by ultra-high energy cosmic rays interacting with air molecules high in the atmosphere, called air showers, can be detected using observatories that cover 10-1000 km^2 . The Pierre Auger Observatory includes a number of methods to detect air showers and covers over 3000 km^2 in the Mendoza Province of Argentina. The Observatory includes a hybrid design by which air showers can be detected by fluorescence detectors while they are developing in the air as well as by an array of surface detectors on the ground. This thesis includes an extensive update to the reconstruction methods used to estimate the trajectory and energy of a cosmic ray using a hexagonal array of water Cherenkov detectors with 750 m spacing. The update was motivated by the inclusion of a new set of particle triggers that were installed in the local stationsthat make up the array. These triggers were designed to be insensitive to muons which make up the primary background for individual stations. Thus, they increase the sensitivity of the array to lower energy parts of air showers and lower energy showers in general.A major component of this work was the characterization of the arrays abilities to detect and sample air showers with the new trigger algorithms. On the level of individual stations, the triggering efficiency and distribution of signals was studied. On the array-level, the efficiency with which the 750 m array detects showers was also calculated for two sets of cosmic ray masses using a dedicated set of air shower simulations based on hadronic interaction models.The second component of this thesis was an improvement of Augers model of air shower development. Due to a lack of understanding of hadronic cross sections in the ultra-high energy regime, empirical models are used to characterize the temporal and spatial distribution of particles within the cascade. The distributionof signal as a function of distance from an air showers central axis was updated, benefiting from the 30% more sampling of the shower front by new-triggered stations. This model is particularly important as it is used to find the expected signal at a fixed reference distance from the axis to estimate the showers size, a quantity highly correlated to energy. These size estimations were then corrected for a number of systematic biases to produce a more precise energy estimator. Finally, the energy estimators were cross-calibrated with the nearly calorimetric energy measurements made by the fluorescence detectors. This allowed for the surface detector to directly estimate energies accurate to within E/E = 14-15%.Motivated by the parameter space where the array can detect showers with full efficiency, two semi-joint data sets were chosen which included energies and zenith angles (E > 10^17 eV, 40 ) and (E 10^17.3 eV,
Download or read book First estimate of the primary cosmic ray energy spectrum above 3 EeV from the Pierre Auger Observatory written by Paul Sommers and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Measurements of air showers are accumulating at an increasing rate while construction proceeds at the Pierre Auger Observatory. Although the southern site is only half complete, the cumulative exposure is already similar to those achieved by the largest forerunner experiments. A measurement of the cosmic ray energy spectrum in the southern sky is reported here. The methods are simple and robust, exploiting the combination of fluorescence detector (FD) and surface detector (SD). The methods do not rely on detailed numerical simulation or any assumption about the chemical composition.
Download or read book Searching for Slow developing Cosmic ray Showers written by Eric William Mayotte and published by . This book was released on 2016 with total page 235 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Pierre Auger Observatory Scaler Mode for the Study of Solar Activity Modulation of Galactic Cosmic Rays written by and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Since data-taking began in January 2004, the Pierre Auger Observatory has been recording the count rates of low energy secondary cosmic ray particles for the self-calibration of the ground detectors of its surface detector array. After correcting for atmospheric effects, modulations of galactic cosmic rays due to solar activity and transient events are observed. Temporal variations related with the activity of the heliosphere can be determined with high accuracy due to the high total count rates. In this study, the available data are presented together with an analysis focused on the observation of Forbush decreases, where a strong correlation with neutron monitor data is found.
Download or read book Search for the Sources of Ultra high Energy Cosmic Rays with the Pierre Auger Observatory written by Markus Lauscher and published by . This book was released on 2016 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Early History of Cosmic Ray Studies written by Yatarō Sekido and published by . This book was released on 1982 with total page 462 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Air Fluorescence Studies at the Pierre Auger Observatory written by Sarah Clay and published by . This book was released on 2007 with total page 177 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Cosmic rays measured by the fluorescence detectors of the Pierre Auger Observatory contain two large sources of error; the degree of scatter created by the atmosphere and the amount of Cherenkov contamination that has been recorded by a detector. When an event is viewed in stereo, these two sources of error can be accounted for directly by using the light profiles calculated by the two detectors. In this thesis accounting for the atmospheric scatter was explored by the use of a program called AerosolMin described in Chapter 5. This program could reconstruct the scattering parameters of the atmosphere by comparing the two profiles of the light produced by an air shower, as calculated by two detectors, as they should be identical in size. When using AerosolMin it was found that only the highest energy events ( > 10 [superscipt 20] eV ) could use this technique and that for the event that occurred at the GPS second of 799137161 a layer of fog was present that could not be accounted for with the simplistic atmospheric profile currently used by the reconstruction software. In Chapter 6 the Cherenkov profiles that had been miscalculated by a detector were replaced to increase the reconstruction statistics. The program that performed this replacement, FdCherenkovReplacer was most successful on events that had recorded a large amount of direct Cherenkov light. The event that occurred at the GPS second of 772256331 is explored in Chapter 7. The Coihueco detector that recorded this event was contaminated by direct Cherenkov light, but when replaced by FdCherenovReplacer it was found to have miscalculated the geometry of the event by 0.4 °." -- Abstract.
Download or read book The Pierre Auger Observatory I written by and published by . This book was released on 2011 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Handbook of Particle Detection and Imaging written by Claus Grupen and published by Springer Science & Business Media. This book was released on 2012-01-08 with total page 1251 pages. Available in PDF, EPUB and Kindle. Book excerpt: The handbook centers on detection techniques in the field of particle physics, medical imaging and related subjects. It is structured into three parts. The first one is dealing with basic ideas of particle detectors, followed by applications of these devices in high energy physics and other fields. In the last part the large field of medical imaging using similar detection techniques is described. The different chapters of the book are written by world experts in their field. Clear instructions on the detection techniques and principles in terms of relevant operation parameters for scientists and graduate students are given.Detailed tables and diagrams will make this a very useful handbook for the application of these techniques in many different fields like physics, medicine, biology and other areas of natural science.
Download or read book Composition Studies of Ultra High Energy Cosmic Rays Using Data of the Pierre Auger Observatory written by Karen Salomé Caballero Mora and published by . This book was released on 2010 with total page 145 pages. Available in PDF, EPUB and Kindle. Book excerpt:
