Download or read book Application of Machine Learning Techniques for Cosmic Ray Event Classification and Implementation of a Real time Ultra high Energy Photon Search with the Surface Detector of the Pierre Auger Observatory written by Lukas Zehrer and published by . This book was released on 2021 with total page 202 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Composition Analysis of Ultrahigh Energy Cosmic Rays Using the Pierre Auger Observatory Surface Detector written by David Scott Barnhill and published by . This book was released on 2006 with total page 374 pages. Available in PDF, EPUB and Kindle. Book excerpt: The origin and composition of ultrahigh energy cosmic rays has been and continues to be a topic of much study and debate. The Pierre Auger Observatory was designed to investigate the highest energy cosmic rays and resolve some of these problems. In this dissertation, I present a description of the Pierre Auger Observatory and a study of the performance of the surface array as well as work done on the photomultiplier tubes used in the surface array. I also present an analysis done on the composition of the events detected in the surface detector paying special attention to a photon primary assumption. Monte carlo simulations of extensive air showers are put through a simulation of the surface detector and observables are compared to real data. The mean behavior of the real data is compared to various baryonic primary assumptions. For photon primaries, a method is described to set an upper limit on the flux of photons based on comparing real events to expected distributions for photon initiated air showers. An upper limit on the photon flux is presented and compared with predictions from various exotic models of cosmic ray origins.
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 Design Calibration and Early Results of a Surface Array for Detection of Ultrahigh Energy Cosmic Rays written by Patrick S. Allison and published by . This book was released on 2007 with total page 343 pages. Available in PDF, EPUB and Kindle. Book excerpt: The difficulties in understanding cosmic rays at ultrahigh energies have been a persistent problem in particle astrophysics for almost 50 years, due to insufficient statistics and large systematic errors. The design of a surface array for the Pierre Auger Observatory, which was intended to resolve these problems, will be discussed, along with its calibration. The surface detector is an array of 1600 water Cherenkov detectors, spaced 1.5 km apart for a total area of 3000 km2, planned to operate continuously for 20 years. The detectors therefore must be inexpensive, low power, easy to deploy, and have a high reliability. Each surface detector station is required to make a high precision measurement of the signal density produced by the air showers induced by cosmic rays over a wide dynamic range, and therefore a calibration system was developed for the array which creates a signal response uniform to within 3%. Finally, early results of the cosmic ray energy spectrum will be calculated, along with the future implications of the array for the field of cosmic ray astrophysics as well as physics in general.
Download or read book Systematic and Statistical Uncertainties in Cosmic Ray Arrival Direction Reconstruction written by Philip Wahrlich and published by . This book was released on 2013 with total page 480 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The Pierre Auger Observatory (PAO) was constructed to study the highest energy cosmic rays (UHECR). A hybrid of ground array and fluorescence detector, it is the largest ultra-high energy cosmic ray detector to date. As such, the PAO detects UHECR in unprecedented amounts, offering unique insights into the nature and origin of these most extraordinarily energetic particles in the universe. In this thesis we improve the accuracy of arrival direction uncertainty estimates for reconstructed events. We validate these improved uncertainty estimators through a number of statistical techniques, involving both recorded and simulated data. Furthermore, we identify and correct a number of systematic errors which arise in algorithmic corner cases. We propose novel techniques for measuring the time synchronisation of each detector in the using recorded air shower data. We use these techniques to measure the synchronisation of each detector across the PAO surface detector and fluorescence detector. Finally, we perform a cursory search for a point source of UHECR at the Galactic centre. A slight over-density of events is measured from the direction of the Galactic centre, however this over-density is not substantial enough to indicate a departure from isotropy." -- page 12.
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 Upper Limits on the Ultra high Energy Cosmic Ray Flux from Unresolved Sources written by Ross E. Burton and published by . This book was released on 2012 with total page 190 pages. Available in PDF, EPUB and Kindle. Book excerpt: The Pierre Auger Observatory is the world's largest ultra-high energy cosmic ray detector. Its goals include answering basic questions about the origins and composition of cosmic rays at the highest energies. We outline the scientific motivation for constructing such an observatory and we highlight some of the significant results produced so far by this world-class instrument. We present the results of our own contributions toward calibrating the timing characteristics of the instrument followed by two alternative techniques for analyzing cosmic ray arrival direction data. The first technique is based on a Bayesian statistical framework and is presented as a solution to some of the difficulties in applying a standard analysis to identify anisotropy in the cosmic ray flux. The second analysis we present is based on a Markov Chain Monte Carlo method for identifying sources of cosmic rays in our arrival direction data. We are able to use our method to set an upper limit of 0.15 per square km per year on the flux from any potential sources producing ultra-high energy cosmic rays with energy E{u2265}3 EeV. We conclude with a proposal for enhancing the already successful observatory with an array of non-imaging Cherenkov detectors. According to our simulation work, such an array could serve as both an independent measure of the cosmic ray energy and, if the array is dense enough, it could also provide insight into the composition of ultra-high energy cosmic rays on an event by event basis.
Download or read book A Study of Ultra high Energy Cosmic Ray Composition and Hadronic Interactions with Data from the Pierre Auger Observatory written by Florin Ioniță and published by . This book was released on 2011 with total page 162 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ultra-high energy cosmic rays are particles of enormous energy -- greater than 1018 eV -- reaching Earth from still mysterious sources. In this thesis, we analyze data from the Pierre Auger Observatory, a giant cosmic ray detector located in Argentina, to derive information on the mass of ultra-high energy cosmic rays and on their hadronic interaction properties. The data show a change of cosmic ray mass composition as a function of energy. We perform a measurement of the proton-air inelastic cross section, yielding sinelp-air =501+24-23 stat+30 -35syst +30-32 composition mb, at an equivalent energy of 57 TeV in the center of mass of a proton-proton collision -- a range yet inaccessible to particle accelerators. The measured cross section is in good agreement with predictions from hadronic interaction models.
Download or read book Searching for Beyond the Standard Model Physics at the Pierre Auger Cosmic Ray Observatory written by Mason Buchanan and published by . This book was released on 2021 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Over the course of three flights, the Antarctic Impulsive Transient Antenna (ANITA) appeared to detect two cosmic ray events from the Earth below, referred to as "Sub-EeV Earth-emergent Cosmic Rays" (SEECRs). This paper turns to the largest cosmic ray detector in the world, the Pierre Auger Observatory, to search for SEECR candidates, set limits on their incidence, and compare the results to the ANITA detections. 10% of the detections made by the Pierre Auger fluorescence detectors (FDs) made from 2007 to 2018 were considered. To isolate SEECR candidates, five cuts were made to the Auger data: the first used computer vision techniques to remove background produced by the Auger laser facilities, the second defined a minimum number of triggered pixels in the FD camera, the third defined a minimum shower zenith angle, the fourth defined a minimum track length on the FD camera, and the fifth defined a minimum probability of the fit of the shower reconstruction. 7 (+8, -4) detections remain after these cuts. Simulations of upgoing events and past exposure comparisons predict 49 SEECR events in the examined data for consistency with ANITA, over 5[sigma] above the observed value. Similar results in the full Pierre Auger data set would widen this discrepancy further.
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 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 Analysis of Correlations Between Ultra High Energy Cosmic Rays Detected by the Pierre Auger Observatory and High Energy Neutrinos Detected by the IceCube Experiment written by George Filippatos and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The sources of ultra high energy cosmic rays detected by the Pierre Auger Observatory are yet unknown. It is natural to expect that cosmic-ray sources could produce high-energy neutrinos detectable by IceCube. In this work we discuss the potential utility and implementation of a correlation search between IceCube and Auger. Any such correlations would allow an unprecedented view of transient astrophysical events, such as a gamma-ray burst. Where previous studies have focused on thehighest energy events(ECR > 57 EeV), weanalyzethe subthreshold data available in the IceCube public dataset and overlapping Auger data down to ECR = 3 EeV. A likelihood estimator is constructed from spatial and temporal correlations based on Monte Carlo simulations of the data. Data is compared to a randomized (scrambled) data set, where any correlations are bound to be accidental, and shown to be consistent with the background hypothesis. We then discuss how this procedure can be used in a real time search, allowing for any coincidences with sufciently high likelihood to be followed up with near real time multiwavelength observations.
Download or read book Microwave Detection of Cosmic Rays and Multi messenger Analysis of the Parameters of Ultra high Energy Astrophysical Sources written by Nathan E. Griffith and published by . This book was released on 2015 with total page 81 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of ultra-high energy (UHE) cosmic particles is frequently characterized by its low statistics, and a central problem of the field is to find novel ways to navigate this challenge. The research presented in this dissertation attempts to address this problem in two ways: first, by investigating microwave radiation as a new method of UHE cosmic ray detection, and second, by using a multi-messenger (proton and neutrino) analysis to determine what current and next generation UHE neutrino detectors may be able to reveal about UHE astrophysical sources. The cosmic ray detector (called AMBER) is primarily a joint collaboration between Ohio State and the University of Hawaii. In May/June 2011 the AMBER experiment was installed at the Pierre Auger Observatory in Malargue, Argentina, and began taking data in coincidence with the observatory's surface detector array. This work presents a description of the experiment, a calibration based on an astrophysical radio source (the Milky Way galaxy), and an analysis of data. The second half of this document describes a multi-messenger analysis performed with co-authors Amy Connolly and Shunsaku Horiuchi on a publication in preparation. Fits to Pierre Auger 2013 data are used in conjunction with a spectral model and simulations of UHE neutrino detectors to explore the UHE source parameters of cosmic evolution and source spectrum cutoff. Constraints provided using the effective areas of the ANITA 3, ARA, and EVA detectors are considered.
Download or read book Measurement of the Ultra High Energy Cosmic Ray Flux Using Data of the Pierre Auger Observatory written by Ioana Codrina Maris and published by . This book was released on 2009 with total page 145 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 Radio Detection of High energy Cosmic Rays at the Pierre Auger Observatory 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 southern Auger Observatory provides an excellent test bed to study the radio detection of extensive air showers as an alternative, cost-effective, and accurate tool for cosmic-ray physics. The data from the radio setup can be correlated with those from the well-calibrated baseline detectors of the Pierre Auger Observatory. Furthermore, human-induced radio noise levels at the southern Auger site are relatively low. We have started an R & D program to test various radio-detection concepts. Our studies will reveal Radio Frequency Interferences (RFI) caused by natural effects such as day-night variations, thunderstorms, and by human-made disturbances. These RFI studies are conducted to optimize detection parameters such as antenna design, frequency interval, antenna spacing and signal processing. The data from our initial setups, which presently consist of typically 3 - 4 antennas, will be used to characterize the shower from radio signals and to optimize the initial concepts. Furthermore, the operation of a large detection array requires autonomous detector stations. The current design is aiming at stations with antennas for two polarizations, solar power, wireless communication, and local trigger logic. The results of this initial phase will provide an important stepping stone for the design of a few tens kilometers square engineering array.
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:
