Corona discharges from grounded rods and 337/777 nm emissions of laboratory long sparks

Tesi en modalitat de compendi de publicacions, amb menció internacionalThis thesis presents an investigation on the signatures of corona discharges from grounded rods under thunderstorms and in the laboratory, with optical detections in the 337/777 nm wavelengths for high voltage sparks. This PhD project is contextualized in the European program: Science and Innovation with thunderstorms (SAINT), funded by the Horizon 2020 / Marie Sklodowska Curie Action (Grant agreement ID: 722337). Under conditions of electrification, charged clouds produce an enhancement of the electric field at the ground level. That, in turn, can lead to corona discharges that produce a space charge layer in the vicinity of grounded structures. The study of this phenomenon is useful for the understanding of lightning-related processes and attachment. In addition to the electrical current obtained from the discharges, another important variable is the optical signature generated by the plasma channels. Emissions in many spectra lines associated with reactions of streamers and leaders with the main components of the atmosphere are relevant for visual observations. This work presents a chapter for current literature review of the processes associated with lightning and the main concepts applied. Then, a detailed description of the instrumentation available for the tests carried out in the laboratory and in the field is provided. The first article of this compendium presents data obtained with experiments of a grounded rod under high background electric field in the laboratory and the field. A limited number of works in the literature have presented such data. An analysis correlating pulse frequency, electric field level and average wind speed is the main novelty of the article. A congress paper annexed in the thesis complements the findings comparing the discharges observed at two other experimental sites. The second article describes a compilation of results obtained in the laboratory for investigating optical signatures in two specific lines of the spectra (337 nm and 777 nm), the ones with stronger emissions in lightning-like events. There is special relevance of such experiments for supporting satellite-based observations of lightning by the Atmosphere-Space Interactions Monitor (ASIM) that perform optical measurements in the same wavelength ranges and the operational lightning imagers such as Geostationary Lightning Mapper (GLM) and the future Meteosat Third Generation Lightning Imager (MTG-LI). The conclusions are presented, together with the prospects for future work following the original results achieved with this PhD. This thesis ends with a detailed description of the dissemination activities (presentation at seminars and conferences, coauthored publications in journals and at conferences) and training activities received throughout this project. Finally, the appendix present additional developments and applications of the sensor developed during this doctorate, comprising experiments performed during a two-month internship at the Eindhoven University of Technology (TU/e), and one section with results for the use of photometers to determine the initiation of an upward leader. Such experiments are particularly interesting for understanding space charge production and in the validation of lightning rods. The concepts applied to the development of a corona discharge current sensor were patented together with Dena Desarrollos, the company where the investigations were carried out during this doctorate.Esta tesis presenta una investigación sobre las huellas de descargas de corona en pararrayos durante tormentas eléctricas y en el laboratorio, con detecciones ópticas en las longitudes de onda de 337/777 nm para descargas de alto voltaje. Este proyecto de doctorado se contextualiza en el programa europeo: Science and Innovation with thunderstorms (SAINT), financiado por la Acción Horizon 2020 / Marie Sklodowska Curie (Acuerdo de subvención ID: 722337). En condiciones de electrificación, las nubes cargadas producen un aumento del campo eléctrico a nivel del suelo. Eso, a su vez, puede ocasionar descargas de corona que producen una capa de carga espacial en las proximidades de las estructuras conectadas a tierra. El estudio de este fenómeno es útil para comprender los procesos y la conexión de los canales de los rayos. Además de la corriente eléctrica obtenida de las descargas, otra variable importante es la huella óptica (las señales ópticas a lo largo del tiempo) generada por los canales de plasma. Las emisiones en muchas líneas espectrales asociadas con reacciones de streamers y líderes con los componentes principales de la atmósfera son relevantes para las observaciones visuales. Este trabajo presenta un capítulo de revisión de la literatura actual sobre los procesos asociados a las descargas atmosféricas y los principales conceptos aplicados. A continuación, se realiza una descripción detallada de la instrumentación disponible para las pruebas realizadas en laboratorio y en campo. El primer artículo de este compendio presenta datos obtenidos con experimentos de una varilla puesta a tierra sujeta a un campo eléctrico de fondo elevado en laboratorio y en campo. Un número limitado de trabajos en la literatura han presentado dichos datos. Un análisis que correlaciona la frecuencia del pulso, el nivel del campo eléctrico y la velocidad media del viento es la principal novedad del artículo. Un artículo presentado en congreso adjunto a la tesis complementa los resultados y realiza una comparación de las descargas observadas en otros dos sitios experimentales. El segundo artículo presenta una recopilación de resultados obtenidos en el laboratorio para la investigación de la huella óptica en dos líneas específicas de los espectros (337 nm y 777 nm), las que tienen emisiones más intensas en los rayos. Existe una relevancia especial de dichos experimentos para respaldar las observaciones de rayos basadas en satélites por el Monitor de Interacciones Atmosfera-Espacio (ASIM) que realiza mediciones ópticas en los mismos rangos de longitud de onda y los generadores de imágenes de rayos operacionales como Geostationary Lightning Mapper (GLM) y el futuro Meteosat Third Generation Lightning Imager (MTG-LI). Se presentan las conclusiones, junto con las perspectivas de trabajo futuro siguiendo los resultados originales alcanzados con este doctorado. Esta tesis finaliza con una descripción detallada de las actividades de difusión (presentación en seminarios y congresos, publicaciones en coautoría en revistas y congresos) y actividades formativas recibidas a lo largo de este proyecto. Finalmente, el apéndice presenta desarrollos y aplicaciones adicionales del sensor desarrollado durante este doctorado, que comprende experimentos realizados durante período de prácticas de dos meses en la Universidad Tecnológica de Eindhoven (TU/e), y un apartado con resultados para el uso de fotómetros para determinar la iniciación de un líder ascendente. Estos experimentos son particularmente interesantes para comprender la producción de cargas espaciales y en la validación de pararrayos. Los conceptos aplicados al desarrollo del sensor de corriente de descarga corona fueron patentados junto con Dena Desarrollos, empresa donde se llevaron a cabo las investigaciones durante este doctorado.Postprint (published version

SeaWiFS technical report series. Volume 5: Ocean optics protocols for SeaWiFS validation

Protocols are presented for measuring optical properties, and other environmental variables, to validate the radiometric performance of the Sea-viewing Wide Field-of-view Sensor (SeaWiFS), and to develop and validate bio-optical algorithms for use with SeaWiFS data. The protocols are intended to establish foundations for a measurement strategy to verify the challenging SeaWiFS accuracy goals of 5 percent in water-leaving radiances and 35 percent in chlorophyll alpha concentration. The protocols first specify the variables which must be measured, and briefly review rationale. Subsequent chapters cover detailed protocols for instrument performance specifications, characterizing and calibration instruments, methods of making measurements in the field, and methods of data analysis. These protocols were developed at a workshop sponsored by the SeaWiFS Project Office (SPO) and held at the Naval Postgraduate School in Monterey, California (9-12 April, 1991). This report is the proceedings of that workshop, as interpreted and expanded by the authors and reviewed by workshop participants and other members of the bio-optical research community. The protocols are a first prescription to approach unprecedented measurement accuracies implied by the SeaWiFS goals, and research and development are needed to improve the state-of-the-art in specific areas. The protocols should be periodically revised to reflect technical advances during the SeaWiFS Project cycle

NASA patent abstracts bibliography: A continuing bibliography. Section 1: Abstracts (supplement 28)

Abstracts are provided for 109 patents and patent applications entered into the NASA Scientific and Technical Information System during the period July 1985 through December 1985. Each entry consists of a citation, an abstract, and in most cases, a key illustration selected from the patent or patent application

Hyper-Kamiokande Design Report

325 pages325 pagesOn the strength of a double Nobel prize winning experiment (Super)Kamiokande and an extremely successful long baseline neutrino programme, the third generation Water Cherenkov detector, Hyper-Kamiokande, is being developed by an international collaboration as a leading worldwide experiment based in Japan. The Hyper-Kamiokande detector will be hosted in the Tochibora mine, about 295 km away from the J-PARC proton accelerator research complex in Tokai, Japan. The currently existing accelerator will be steadily upgraded to reach a MW beam by the start of the experiment. A suite of near detectors will be vital to constrain the beam for neutrino oscillation measurements. A new cavern will be excavated at the Tochibora mine to host the detector. The experiment will be the largest underground water Cherenkov detector in the world and will be instrumented with new technology photosensors, faster and with higher quantum efficiency than the ones in Super-Kamiokande. The science that will be developed will be able to shape the future theoretical framework and generations of experiments. Hyper-Kamiokande will be able to measure with the highest precision the leptonic CP violation that could explain the baryon asymmetry in the Universe. The experiment also has a demonstrated excellent capability to search for proton decay, providing a significant improvement in discovery sensitivity over current searches for the proton lifetime. The atmospheric neutrinos will allow to determine the neutrino mass ordering and, together with the beam, able to precisely test the three-flavour neutrino oscillation paradigm and search for new phenomena. A strong astrophysical programme will be carried out at the experiment that will detect supernova neutrinos and will measure precisely solar neutrino oscillation

NASA Tech Briefs, December 2009

Topics include: A Deep Space Network Portable Radio Science Receiver; Detecting Phase Boundaries in Hard-Sphere Suspensions; Low-Complexity Lossless and Near-Lossless Data Compression Technique for Multispectral Imagery; Very-Long-Distance Remote Hearing and Vibrometry; Using GPS to Detect Imminent Tsunamis; Stream Flow Prediction by Remote Sensing and Genetic Programming; Pilotless Frame Synchronization Using LDPC Code Constraints; Radiometer on a Chip; Measuring Luminescence Lifetime With Help of a DSP; Modulation Based on Probability Density Functions; Ku Telemetry Modulator for Suborbital Vehicles; Photonic Links for High-Performance Arraying of Antennas; Reconfigurable, Bi-Directional Flexfet Level Shifter for Low-Power, Rad-Hard Integration; Hardware-Efficient Monitoring of I/O Signals; Video System for Viewing From a Remote or Windowless Cockpit; Spacesuit Data Display and Management System; IEEE 1394 Hub With Fault Containment; Compact, Miniature MMIC Receiver Modules for an MMIC Array Spectrograph; Waveguide Transition for Submillimeter-Wave MMICs; Magnetic-Field-Tunable Superconducting Rectifier; Bonded Invar Clip Removal Using Foil Heaters; Fabricating Radial Groove Gratings Using Projection Photolithography; Gratings Fabricated on Flat Surfaces and Reproduced on Non-Flat Substrates; Method for Measuring the Volume-Scattering Function of Water; Method of Heating a Foam-Based Catalyst Bed; Small Deflection Energy Analyzer for Energy and Angular Distributions; Polymeric Bladder for Storing Liquid Oxygen; Pyrotechnic Simulator/Stray-Voltage Detector; Inventions Utilizing Microfluidics and Colloidal Particles; RuO2 Thermometer for Ultra-Low Temperatures; Ultra-Compact, High-Resolution LADAR System for 3D Imaging; Dual-Channel Multi-Purpose Telescope; Objective Lens Optimized for Wavefront Delivery, Pupil Imaging, and Pupil Ghosting; CMOS Camera Array With Onboard Memory; Quickly Approximating the Distance Between Two Objects; Processing Images of Craters for Spacecraft Navigation; Adaptive Morphological Feature-Based Object Classifier for a Color Imaging System; Rover Slip Validation and Prediction Algorithm; Safety and Quality Training Simulator; Supply-Chain Optimization Template; Algorithm for Computing Particle/Surface Interactions; Cryogenic Pupil Alignment Test Architecture for Aberrated Pupil Images; and Thermal Transport Model for Heat Sink Design

Hyper-Kamiokande Design Report

On the strength of a double Nobel prize winning experiment (Super)Kamiokande and an extremely successful long baseline neutrino programme, the third generation Water Cherenkov detector, Hyper-Kamiokande, is being developed by an international collaboration as a leading worldwide experiment based in Japan. The Hyper-Kamiokande detector will be hosted in the Tochibora mine, about 295 km away from the J-PARC proton accelerator research complex in Tokai, Japan. The currently existing accelerator will be steadily upgraded to reach a MW beam by the start of the experiment. A suite of near detectors will be vital to constrain the beam for neutrino oscillation measurements. A new cavern will be excavated at the Tochibora mine to host the detector. The experiment will be the largest underground water Cherenkov detector in the world and will be instrumented with new technology photosensors, faster and with higher quantum efficiency than the ones in Super-Kamiokande. The science that will be developed will be able to shape the future theoretical framework and generations of experiments. Hyper-Kamiokande will be able to measure with the highest precision the leptonic CP violation that could explain the baryon asymmetry in the Universe. The experiment also has a demonstrated excellent capability to search for proton decay, providing a significant improvement in discovery sensitivity over current searches for the proton lifetime. The atmospheric neutrinos will allow to determine the neutrino mass ordering and, together with the beam, able to precisely test the three-flavour neutrino oscillation paradigm and search for new phenomena. A strong astrophysical programme will be carried out at the experiment that will also allow to measure precisely solar neutrino oscillation

Index to NASA Tech Briefs, 1972

Abstracts of 1972 NASA Tech Briefs are presented. Four indexes are included: subject, personal author, originating center, and Tech Brief number

Laser Communication Satellite Experiment /LCSE/

Equipment descriptions and procedures for Laser Communication Satellite Experiment /LCSE

Science Mission Directorate TechPort Records for 2019 STI-DAA Release

The role of the Science Mission Directorate (SMD) is to enable NASA to achieve its science goals in the context of the Nation's science agenda. SMD's strategic decisions regarding future missions and scientific pursuits are guided by Agency goals, input from the science community including the recommendations set forth in the National Research Council (NRC) decadal surveys and a commitment to preserve a balanced program across the major science disciplines. Toward this end, each of the four SMD science divisions -- Heliophysics, Earth Science, Planetary Science, and Astrophysics -- develops fundamental science questions upon which to base future research and mission programs

NASA Tech Briefs, Fall 1982

Topics include: NASA TU Services: Technology Utilization services that can assist you in learning about and applying NASA technology. New Product Ideas: A summary of selected innovations of value to manufacturers for the develop ment of new products; Electronic Components and Circuits; Electronic Systems; Physical Sciences; Materials; Life Sciences; Mechanics; Machinery; Fabrication Technology; Mathematics and Information Sciences