Proceedings of the Second Airborne Imaging Spectrometer Data Analysis Workshop

Topics addressed include: calibration, the atmosphere, data problems and techniques, geological research, and botanical and geobotanical research

Proceedings of the Airborne Imaging Spectrometer Data Analysis Workshop

The Airborne Imaging Spectrometer (AIS) Data Analysis Workshop was held at the Jet Propulsion Laboratory on April 8 to 10, 1985. It was attended by 92 people who heard reports on 30 investigations currently under way using AIS data that have been collected over the past two years. Written summaries of 27 of the presentations are in these Proceedings. Many of the results presented at the Workshop are preliminary because most investigators have been working with this fundamentally new type of data for only a relatively short time. Nevertheless, several conclusions can be drawn from the Workshop presentations concerning the value of imaging spectrometry to Earth remote sensing. First, work with AIS has shown that direct identification of minerals through high spectral resolution imaging is a reality for a wide range of materials and geological settings. Second, there are strong indications that high spectral resolution remote sensing will enhance the ability to map vegetation species. There are also good indications that imaging spectrometry will be useful for biochemical studies of vegetation. Finally, there are a number of new data analysis techniques under development which should lead to more efficient and complete information extraction from imaging spectrometer data. The results of the Workshop indicate that as experience is gained with this new class of data, and as new analysis methodologies are developed and applied, the value of imaging spectrometry should increase

Probing atmospheric mixing and leptonic CP violation in current and future long baseline oscillation experiments

FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPWe perform realistic simulations of the current and future long baseline experiments such as T2K, NOvA, DUNE and T2HK in order to determine their ultimate potential in probing neutrino oscillation parameters. We quantify the potential of these experiments to underpin the octant of the atmospheric angle 023 as well as the value and sign of the CP phase delta(CP) We do this both in general, as well as within the predictive framework of a previously proposed [1] benchmark theory of neutrino oscillations which tightly correlates theta(23) and delta(CP).771524531FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESPFUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULO - FAPESP2014/05133-12014/19164-62015/16809-9This research is supported by the Spanish grants FPA2014- 58183-P, Multidark CSD2009-00064, SEV-2014-0398 (MINECO) and PROMETEOII/2014/084 (Generalitat Valenciana). P. S. P. acknowledges the support of FAPESP grant 2014/05133-1, 2015/16809-9 and 2014/19164-6

Coulomb corrections to e+e−e^+ e^- production in ultra-relativistic nuclear collisions

The purpose of this paper is to explain the discrepancies existing in the literature relative to $e^+e^-$ pair production in peripheral heavy ion collisions at ultra-relativistic energies. A controversial issue is the possible cancellation of Coulomb corrections to the Born term in the pair production cross-section. Such a cancellation has been observed in a recent approach based on finding retarded solutions of the Dirac equation, but does not seem to hold in a perturbative approach. We show in this paper that the two approaches are in fact calculating different observables: the perturbative approach gives the exclusive cross-section of single pair production, while the other method gives the inclusive cross-section. We have also performed a thorough study of the electron propagator in the non-static background field of the two nuclei, the conclusion of which is that the retarded propagator is in the ultra-relativistic limit a much simpler object than the Feynman propagator, and can be calculated exactly.Comment: 31 pages LaTeX document, 10 postscript figures (expanded 3rd section, version to be published in Nucl. Phys. A

Significance of sedimentary organic matter input for shale gas generation potential of Mississippian Mudstones, Widmerpool Gulf, UK

Carboniferous mudstones in central and northern England are shale gas prospects but the controls on the amount and composition of organic matter are not well understood, even though these parameters define the volumes of gas generated in fine-grained sediments. Organic matter in samples from basinal late Mississippian (Arnsbergian) mudstones in the Widmerpool Gulf was characterised by using semi-quantitative (n = 58) and quantitative palynofacies (n = 16) analyses, sporomorph counts and bulk rock geochemistry (total organic carbon, δ13C of bulk organic matter, Rock-Eval Pyrolysis). The results of this study suggest that most organic matter at this location was delivered to the sediment-water interface as aggregates of a granular translucent type of amorphous organic matter (AOMGr, mean 66.7±19.3%) via hemipelagic suspension settling. AOMGr represents fragments of algal material with subordinate inclusions of small plant fragments and pyrite framboids held together by microbial colonies. AOMBr (brown granular amorphous organic matter) is the second most abundant group (mean 15.6±8.5%) comprising similar microbial colonies that grew on suspended land plant-derived fragments in the water column. Palynofacies components representing clearly terrestrial organic matter are much less abundant and include gelified organic matter (G, mean 9.6±12.6%), black phytoclasts (PhBl mean 2.7±4.7%), brown phytoclasts (PhBr, mean 3.3±3.6%) and sporomorphs (mean 1.4±1.3%). Sediment delivery processes influence the balance between terrestrial organic matter and AOMGr. During low sea-level times, turbidity currents and debris flows delivered terrestrial organic matter (representing 12 to 40% of the palynofacies). Kerogen composition varies between Type II and III. In contrast, thin-bedded carbonate-bearing mudstones deposited during rising and high sea-level contain up to 95% AOMGr and these high abundances correspond to higher total organic carbon. Carbonate and AOMGr were generated by high bioproductivity in the water column. Type II (oil- and gas-prone) kerogens are dominant in these mudstones and therefore these intervals represent the best potential targets for thermogenic shale gas

In-flight radiometric calibration of the Airborne Visible/Infrared Imaging Spectrometer (AVIRIS)

A reflectance-based method was used to provide an analysis of the in-flight radiometric performance of AVIRIS. Field spectral reflectance measurements of the surface and extinction measurements of the atmosphere using solar radiation were used as input to atmospheric radiative transfer calculations. Five separate codes were used in the analysis. Four include multiple scattering, and the computed radiances from these for flight conditions were in good agreement. Code-generated radiances were compared with AVIRIS-predicted radiances based on two laboratory calibrations (pre- and post-season of flight) for a uniform highly reflecting natural dry lake target. For one spectrometer (C), the pre- and post-season calibration factors were found to give identical results, and to be in agreement with the atmospheric models that include multiple scattering. This positive result validates the field and laboratory calibration technique. Results for the other spectrometers (A, B and D) were widely at variance with the models no matter which calibration factors were used. Potential causes of these discrepancies are discussed