Download or read book Measurement of the Flux of Ultra high Energy Cosmic Rays by the Telescope Array FADC Fluorescence Detectors written by Sean Stratton and published by . This book was released on 2012 with total page 110 pages. Available in PDF, EPUB and Kindle. Book excerpt: Ultra-high energy cosmic rays (UHECRs) produce the most powerful collisions between single particles and atmospheric matter. They have been studied since the early 20th century yet, to this date, there is no clear answer as to the acceleration process responsible for their produc-tion. The Telescope Array Project is an experiment designed to observe the showers of particles produced as by-products of the interactions between UHECRs and the atmosphere. As a hybrid experiment, it currently utilizes 38 fluorescence detectors (FDs) divided between three sites over-looking an array of 507 surface detectors (SDs). The project's mission is to study the energy, composition and origin of UHECRs using a variety of techniques which may include some or all of the experiment's apparatus. This document, in particular, is a presentation of the UHECR en-ergy spectrum measured at Telescope Array using the fluorescence detection technique in mo-nocular mode. Only data from the 24 FDs at Black Rock Mesa (BR) and Long Ridge (LR) sta-tions are used here.
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 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 Instruments and Methods for the Radio Detection of High Energy Cosmic Rays written by Frank Schröder and published by Springer Science & Business Media. This book was released on 2012-12-14 with total page 199 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cosmic rays consist of elementary particles with enormous energy which originate from outside our solar system and constantly hit the Earth’s atmosphere. Where do these cosmic rays originate? How does nature accelerate the cosmic-ray particles to energies with orders of magnitude beyond the limits of manmade particle accelerators? What can we learn by measuring the interactions of the cosmic rays with the atmosphere? Digital radio-antenna arrays offer a promising, complementary measurement method for high-energy cosmic rays. This thesis reports on substantial advances in the development of the radio technique, which will be used to address these questions in future experiments.
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 Detection Techniques of Radio Emission from Ultra High Energy Cosmic Rays written by Chad Michael Morris and published by . This book was released on 2009 with total page 109 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: We discuss recent and future efforts to detect radio signals from extended air showers at the Pierre Auger Observatory in Malargue, Argentina. With the advent of low-cost, high-performance digitizers and robust digital signal processing software techniques, radio detection of cosmic rays has resurfaced as a promising measurement system. The inexpensive nature of the detector media (metallic wires, rods or parabolic dishes) and economies of scale working in our favor (inexpensive high-quality C-band amplifiers and receivers) make an array of radio antennas an appealing alternative to the expense of deploying an array of Cherenkov detector water tanks or 'fly's eye' optical telescopes for fluorescence detection. The calorimetric nature of the detection and the near 100% duty cycle gives the best of both traditional detection techniques. The history of cosmic ray detection will be discussed. A short review on the astrophysical properties of cosmic rays and atmospheric interactions will lead into a discussion of two radio emission channels that are currently being investigated.
Download or read book Measurement of the Flux of Ultra High Energy Cosmic Rays Using Very Inclined Extensive Air Showers Measured at the Pierre Auger Observatory written by Talianna Schmidt and published by . This book was released on 2010 with total page 160 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Physics and Astrophysics of Ultra High Energy Cosmic Rays written by M. Lemoine and published by . This book was released on 2014-01-15 with total page 340 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Measuring the Composition of Cosmic Rays with the SPASE and AMANDA Detectors written by Kathrine Rawlins and published by . This book was released on 2001 with total page 234 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book The Composition of Ultra High Energy Cosmic Rays Through Hybrid Analysis at Telescope Array written by Elliott L. Barcikowski and published by . This book was released on 2011 with total page 166 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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 Measurement of the Ultra High Energy Cosmic Ray Flux from Data of Very Inclined Showers at the Pierre Auger Observatory written by Hans Peter Dembinski and published by . This book was released on 2009 with total page 238 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Systematic Uncertainties in Cosmic Ray Energies Measured by the Auger Fluorescence Detectors written by Vanessa Catherine Holmes and published by . This book was released on 2011 with total page 206 pages. Available in PDF, EPUB and Kindle. Book excerpt: This work investigates the processes used to reconstruct extensive air showers induced in the atmosphere by ultra high energy cosmic rays. It contributes to the efforts of the Pierre Auger Collaboration, whose members are working to solve many mysteries behind the phenomenon of these particles. Specifically my work has focused on the use of the Pierre Auger Observatory's fluorescence detectors to determine cosmic ray energies. I have investigated ways to reduce the systematic uncertainties involved in the reconstruction process. To accurately reconstruct an extensive air shower in order to determine properties of the primary cosmic ray, we need to be able to model how the atmosphere will affect its production and propagation. A precise knowledge of how to interpret the signals received at our detectors is also needed. Inaccurate models or incorrect assumptions may lead to large errors in the shape and magnitude of the true energy spectrum of the cosmic rays which we observe at Earth. We wish to use the information that we gather from this experiment about the energy spectrum, anisotropy and composition of cosmic rays to help locate and study sources, and the acceleration mechanisms that produce their incredible energies. If we are inaccurately reconstructing these extensive air showers then this could lead to incorrect theories being developed. The systematic uncertainties that I have investigated and are presented in my thesis are: An unexplained halo of light around the shower track at the fluorescence detector which led me to develop a parameterisation for singly scattered Cherenkov light that we receive at the fluorescence detectors. This parameterisation is a function of shower evolution, distance to the shower, scattering probability and angular distance from the tracks centre ; Uncertainty in the nitrogen fluorescence yield due to the humidity dependence of collisional quenching. To take this dependence into account I constructed monthly vapour pressure profiles using data acquired from radiosonde launches conducted above the Pierre Auger Observatory. As the fluorescence detectors are unable to detect air showers on overcast days, launches conducted in overcast conditions were identified and excluded, using infra-red cloud camera data and sky temperature measurements. Methods to reduce the uncertainty on the vapour pressure profiles uncertainties were also investigated ; Uncertainty in the methods used to interpret the light seen by the fluorescence detectors. When comparing two methods, I found that they differed in their approach to take into account the lateral shower width at large shower ages. This was because the initial parameterisation was only constructed up to shower ages of 1.2. I used the simulation package CORSIKA to check whether the original parameterisation was still valid at ages up to 1.5, and to check its validity down to primary particle energies of 1017eV. In addressing these systematic uncertainties, we now have a better understanding of the light that we receive at the Fluorescence Detectors, and of how to collect this light for use in reconstructing extensive air showers to determine the cosmic ray energy spectrum, cosmic ray composition and their arrival directions.
Download or read book The Energy Spectrum of Ultra High Energy Cosmic Rays Measured by the High Resolution Fly s Eye Detectors microform written by Reil, Kevin and published by Ann Arbor, Mich. : University Microfilms International. This book was released on 2002 with total page 352 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book On the Energy Estimation of Ultra High Energy Cosmic Rays Observed with the Surface Detector Array written by H. Y. Dai and published by . This book was released on 1988 with total page 31 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Physics Briefs written by and published by . This book was released on 1993 with total page 1058 pages. Available in PDF, EPUB and Kindle. Book excerpt:
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...
