Development of new tools and devices for CMB and foreground data analysis and future experiments

The discovery of the Cosmic Microwave Background (CMB) radiation in 1965 is one of the fundamental milestones supporting the Big Bang theory. The CMB is one of the most important source of information in cosmology. The excellent accuracy of the recent CMB data of WMAP and Planck satellites confirmed the validity of the standard cosmological model and set a new challenge for the data analysis processes and their interpretation. In this thesis we deal with several aspects and useful tools of the data analysis. We focus on their optimization in order to have a complete exploitation of the Planck data and contribute to the final published results. The issues investigated are: the change of coordinates of CMB maps using the HEALPix package, the problem of the aliasing effect in the generation of low resolution maps, the comparison of the Angular Power Spectrum (APS) extraction performances of the optimal QML method, implemented in the code called BolPol, and the pseudo-Cl method, implemented in Cromaster. The QML method has been then applied to the Planck data at large angular scales to extract the CMB APS. The same method has been applied also to analyze the TT parity and the Low Variance anomalies in the Planck maps, showing a consistent deviation from the standard cosmological model, the possible origins for this results have been discussed. The Cromaster code instead has been applied to the 408 MHz and 1.42 GHz surveys focusing on the analysis of the APS of selected regions of the synchrotron emission. The new generation of CMB experiments will be dedicated to polarization measurements, for which are necessary high accuracy devices for separating the polarizations. Here a new technology, called Photonic Crystals, is exploited to develop a new polarization splitter device and its performances are compared to the devices used nowadays

Optimized, versatile diamond-based sensors : materials, fabrication and novel applications

Quantum sensing as one of the backbones of the second quantum revolution is about to enable a variety of novel applications requiring good spatial resolution and sensitivity. The atomic-sized, negatively charged nitrogen vacancy (NV) color center in single crystal diamond was found to enable magnetic field sensing at the nanoscale. Magnetic sensing using NV centers is enabled by bright photostable emission and optically addressable spin states. Due to its extraordinary coherence time, sensitivities of few nT\Hz^(1/2) can be achieved under ambient conditions. To enhance the spatial resolution of NV-based sensing, it is necessary to approach the NV center to a sample to investigate. Here, a challenging nanofabrication procedure is needed to sculpt the diamond into a photonic nanostructure usable as a scanning probe tip. In this thesis, we report on the progress towards optimizing the applicability of NV centers as quantum sensors. We investigate novel material systems promising for upscaling nanofabrication. By introducing a novel approach to enhance the adhesion of etch masks and novel plasma treatments, we optimize the reliability of the nanofabrication procedure. In addition, we study a novel near-field interaction-based sensing resource. By investigating the interaction of shallow NV centers with a monolayer of WSe2, we were able to show simultaneous near-field and magnetic field sensing using the NV center.Als eine der Säulen der zweiten Quanten-Revolution ermöglicht die Quantensensorik viele neue Anwendungen, die eine gute Ortsau ösung und Sensitivität benötigen. Das atomar kleine, negativ geladene Stickstoff-Fehlstellen (NV) Farbzentrum in einkristallinem Diamant ermöglicht das Detektieren von Magnetfeldern auf Nanomaÿstäben. Magnetfelddetektion mittels NV Zentren wird durch helle, photostabile Emission und optisch adressierbare Spin-Zustände ermöglicht. Aufgrund seiner auÿergewöhnlichen Kohärenzzeit erreicht es Sensitivitäten von einigen nT/Hz^(1/2) unter Umgebungsbedingungen. Zur Verbesserung der Ortsauflösung NV-basierter Sensorik, muss das NV-Zentrum an die zu untersuchende Probe angenähert werden. Dies erfordert einen herausfordernden Nanfabrikationsprozess, um den Diamanten in eine photonische Struktur zu formen, die als Rastersonde nutzbar ist. Diese Arbeit beschreibt Fortschritte zur Optimierung der Anwendbarkeit von NV-Zentren als Quantensensoren. Wir untersuchen neuartige Materialien, die vielversprechend für die Skalierbarkeit des Prozesses sind. Durch neue Ansätze zur Verbesserung der Adhäsion von Ätzmasken und neue Plasmabehandlungen optimieren wir die Zuverlässigkeit der Nanofabrikation. Zudem analysieren wir einen neuen, auf Nahfeldwechselwirkung beruhenden Sensorikansatz. Bei der Untersuchung der Wechselwirkung von oberflächennahen NV-Zentren mit monolagigem WSe2 konnten wir das gleichzeitige Erfassen von Nah- und magnetischen Feldern mittels NV-Zentren zeigen

Characterizing radio channels : the science and technology of propagation and interference, 1900-1935

Thesis (Ph. D. in History and Social Study of Science and Technology (HASTS))--Massachusetts Institute of Technology, Program in Science, Technology and Society, 2004.Includes bibliographical references (p. 409-429).Guglielmo Marconi's trans-Atlantic wireless experiment in 1900 marked the beginning of a communication revolution that transformed the open space above the earth into channels of information flow. This dissertation grapples with the historical conditions that gave rise to such a transformation: the studies of radio-wave propagation and the treatments of radio interferences in early twentieth-century America and Western Europe. The part on propagation examines the debate between the surface diffraction theory and the atmospheric reflection theory for long waves, the development of the ionic refraction theory for short waves, the evidential quests for the existence of the ionosphere, and the studies of the geomagnetic effects on propagation. The part on interferences focuses on the engineering efforts toward the characterization of atmospheric noise and signal-intensity fluctuations, the policies of radio-channel allocation for fighting man-made interference, and the scientific research into electronic tube noise. By the mid-30s, the results from these endeavors had considerably improved the quality of radio communication. Characterizing Radio Channels builds a bridge between the history of science and the history of technology by inspecting an immaterial engineering entity--radio channels--whose control required significant scientific research. In the history of science, it contributes to an integrated study of electrical physics and geophysics. In the history of technology, it enriches radio history, epistemology of engineering knowledge, consumer studies, and the studies of technological policies. Combining both fields with the concept of radio channels enables a new understanding of the historical conditions that made the information society(cont.) social factors that facilitated the modern research organizations in academia, industry, governments and the military.by Chen-Pang Yeang.Ph.D.in History and Social Study of Science and Technology (HAST

Brain and Human Body Modeling

This open access book describes modern applications of computational human modeling with specific emphasis in the areas of neurology and neuroelectromagnetics, depression and cancer treatments, radio-frequency studies and wireless communications. Special consideration is also given to the use of human modeling to the computational assessment of relevant regulatory and safety requirements. Readers working on applications that may expose human subjects to electromagnetic radiation will benefit from this book’s coverage of the latest developments in computational modelling and human phantom development to assess a given technology’s safety and efficacy in a timely manner. Describes construction and application of computational human models including anatomically detailed and subject specific models; Explains new practices in computational human modeling for neuroelectromagnetics, electromagnetic safety, and exposure evaluations; Includes a survey of modern applications for which computational human models are critical; Describes cellular-level interactions between the human body and electromagnetic fields

The Twenty-Fifth Lunar and Planetary Science Conference. Part 3: P-Z

Various papers on lunar and planetary science are presented, covering such topics as: impact craters, tektites, lunar geology, lava flow, geodynamics, chondrites, planetary geology, planetary surfaces, volcanology, tectonics, topography, regolith, metamorphic rock, geomorphology, lunar soil, geochemistry, petrology, cometary collisions, geochronology, weathering, and meteoritic composition