Background Studies for the ECHo Experiment
Author : Alexander Sebastian Göggelmann
Publisher :
Page : 0 pages
File Size : 33,91 MB
Release : 2022
Category :
ISBN :
Author : Alexander Sebastian Göggelmann
Publisher :
Page : 0 pages
File Size : 33,91 MB
Release : 2022
Category :
ISBN :
Author : Alexander Sebastian Göggelmann (geb. Ziegenbein)
Publisher :
Page : 0 pages
File Size : 34,73 MB
Release : 2022
Category :
ISBN :
The aim of the Electron Capture Ho-163 (ECHo) experiment is the determination of the effective electron neutrino mass. This should be achieved by analyzing the Ho-163 electron capture (EC) spectrum recorded by Ho-implanted metallic magnetic calorimeters (MMCs) arranged in a pixelized array. The influence of the neutrino mass on the shape of the Ho-163 EC spectrum is strongest at the endpoint region around Q_EC ~ 2.8 keV. However, the fraction of events in the region of interest (ROI) of 10 eV below Q_EC is only in the order of 10^-9 resulting in low count rates of the order of 10^-4 counts per day and pixel for an activity of 1 Bq of Ho-163 per MMC pixel. Thus, the description of the endpoint region has to rely on the precise knowledge of the expected Ho-163 events and background events. The background in the ROI is aimed to be dominated by unresolved pile-up, which is expected to be in the order of 10^-6 to 10^-5 counts per day and pixel. In this work, the expected background caused by cosmic muons and natural occurring radionuclides located in the next surrounding of the detector arrays is discussed. For this purpose, Monte Carlo simulations based on the GEANT4 framework are performed to study the energy deposition in the MMCs due to muons and radiation produced by muons propagating through materials surrounding the detector array. Results of screening measurements of materials used in the first stage of the ECHo experiment, ECHo-1k, are used as basis for simulations of radioisotopes in materials close to the detector array. The results of the simulations of radioactive contamination is compared with a background spectra acquired by non-Ho-implanted pixels, while the simulation of muonic background is compared to data acquired by a measurement including an active muon veto installed around the cryostat used for the operation of the detectors. A pulse shape analysis of pulses received by the MMCs is used to identify Ho-163 induced and similar events caused by particles stopped in the MMCs, and is used to identify events generated by muons.
Author : National Research Council (U.S.). Committee on Undersea Warfare
Publisher :
Page : 156 pages
File Size : 11,93 MB
Release : 1950
Category : Underwater acoustics
ISBN :
Author : Mariana L Melcón
Publisher : Frontiers E-books
Page : 208 pages
File Size : 12,44 MB
Release : 2014-11-24
Category : Physiology
ISBN : 2889193470
Echolocation has evolved in different groups of animals, from bats and cetaceans to birds and humans, and enables localization and tracking of objects in a dynamic environment, where light levels may be very low or absent. Nature has shaped echolocation, an active sense that engages audiomotor feedback systems, which operates in diverse environments and situations. Echolocation production and perception vary across species, and signals are often adapted to the environment and task. In the last several decades, researchers have been studying the echolocation behavior of animals, both in the air and underwater, using different methodologies and perspectives. The result of these studies has led to rich knowledge on sound production mechanisms, directionality of the sound beam, signal design, echo reception and perception. Active control over echolocation signal production and the mechanisms for echo processing ultimately provide animals with an echoic scene or image of their surroundings. Sonar signal features directly influence the information available for the echolocating animal to perceive images of its environment. In many echolocating animals, the information processed through echoes elicits a reaction in motor systems, including adjustments in subsequent echolocation signals. We are interested in understanding how echolocating animals deal with different environments (e.g. clutter, light levels), tasks, distance to targets or objects, different prey types or other food sources, presence of conspecifics or certain predators, ambient and anthropogenic noise. In recent years, some researchers have presented new data on the origins of echolocation, which can provide a hint of its evolution. Theoreticians have addressed several issues that bear on echolocation systems, such as frequency or time resolution, target localization and beam-forming mechanisms. In this Research Topic we compiled recent work that elucidates how echolocation – from sound production, through echolocation signals to perception- has been shaped by nature functioning in different environments and situations. We strongly encouraged comparative approaches that would deepen our understanding of the processes comprising this active sense.
Author :
Publisher :
Page : 484 pages
File Size : 15,92 MB
Release : 1993
Category : Aeronautics
ISBN :
Author : Stanford University Stanford Electronics Laboratories
Publisher :
Page : 70 pages
File Size : 28,49 MB
Release : 1960
Category :
ISBN :
Author : Victor V. Rodin
Publisher : Bentham Science Publishers
Page : 244 pages
File Size : 19,91 MB
Release : 2018-11-02
Category : Science
ISBN : 1681086298
This book describes nuclear magnetic resonance (NMR) methods which are used to study translational dynamics of molecules in different complex systems including systems made of synthetic and natural polymers, tissues and the porous heterogeneous systems of different types, such as cement and wood. The results of proton spin-lattice and spin-spin relaxation, cross-relaxation, pulse field gradient (PFG) NMR in studying diffusion properties and dynamics of molecules in polymer systems of different complexity are reported. In addition to these methods, reports on the use of the double-quantum-filtered (DQF) NMR technique in a study of slow molecular dynamics and properties of systems with anisotropic properties, such as water in hardening cement pastes, are presented. The book also covers applications of one and two dimensional NMR techniques. This book is a useful reference for readers learning different NMR techniques and their applications in civil engineering and biochemistry.
Author : Robert C. Schaller
Publisher :
Page : 104 pages
File Size : 44,66 MB
Release : 1982
Category : Ice
ISBN :
This report summarizes previous melting-layer research both within and outside AFGL and provides recommendations for future research in the melting layer. An extensive literature search provided a bibliography of previous research. This bibliography is included as an appendix. Several definitions of the top and bottom of the melting layer are presented and discussed. Aggregation and breakup appear to be the chief microphysical processes that determine the particle-size spectrum of snow and ice that enter the melting layer. Studies of the actual melting process and of the melting layer as seen by radar are presented. Microphysical and thermodynamic characteristics are discussed. Dynamic considerations are mentioned. Previously gathered aircraft data are reviewed, and recommendations are made for future aircraft and radar data-gathering efforts. (Author).
Author : Guangsheng He
Publisher :
Page : 667 pages
File Size : 42,33 MB
Release : 2015
Category : Science
ISBN : 0198702760
This book provides a comprehensive presentation on most of the major topics in nonlinear optics and photonics, with equal emphasis on principles, experiments, techniques, and applications. It covers many major new topics including optical solitons, multi-photon effects, nonlinear photoelectric effects, fast and slow light , and Terahertz photonics. Chapters 1-10 present the fundamentals of modern nonlinear optics, and could be used as a textbook with problems provided at the end of each chapter. Chapters 11-17 cover the more advanced topics of techniques and applications of nonlinear optics and photonics, serving as a highly informative reference for researchers and experts working in related areas. There are also 16 pages of color photographs to illustrate the visual appearances of some typical nonlinear optical effects and phenomena. The book could be adopted as a textbook for both undergraduates and graduate students, and serve as a useful reference work for researchers and experts in the fields of physics, quantum electronics, and laser technology. To request a copy of the Solutions Manual, visit: //global.oup.com/uk/academic/physics/admin/solutions
Author : Igor V. Yevseyev
Publisher : CRC Press
Page : 159 pages
File Size : 32,44 MB
Release : 2004-02-24
Category : Science
ISBN : 1134453914
In this book, the authors derive the theory of elastic depolarizing collisions and describe their importance in some nonlinear electromagnetic phenomena in gaseous media. The formation of photon echo and a description of its various types in gaseous media are then presented. The authors show that the characteristics of the corresponding signals depend essentially on elastic depolarizing collisions. They also consider the advantages of a new kind of photon echo spectroscopy: polarization photon echo-spectroscopy. A high-level, specialized treatment, Depolarizing Collisions in Nonlinear Electrodynamics will appeal to researchers and advanced graduates in nonlinear optics and quantum electronics.