A Skylab program for the International Hydrological Decade (IHD)

There are no author-identified significant results in this report

A Skylab program for the International Hydrological Decade (IHD)

The author has identified the following significant results. Demonstration of the procedure for utilizing the model relating red and IR reflectance to surface soil moisture over regions of variable vegetation cover indicates that remote sensing may be able to make direct inputs into determination of this hydrologic parameter

An ERTS-1 investigation for Lake Ontario and its basin

The author has identified the following significant results. Methods of manual, semi-automatic, and automatic (computer) data processing were evaluated, as were the requirements for spatial physiographic and limnological information. The coupling of specially processed ERTS data with simulation models of the watershed precipitation/runoff process provides potential for water resources management. Optimal and full use of the data requires a mix of data processing and analysis techniques, including single band editing, two band ratios, and multiband combinations. A combination of maximum likelihood ratio and near-IR/red band ratio processing was found to be particularly useful

A Skylab program for the International Hydrological Decade (IHD)

There are no author-identified significant results in this report

Use of LANDSAT data to assess waterfowl habitat quality

The author has identified the following significant results. The capability of mapping ponds over a very large area was demonstrated, with multidate, multiframe LANDSAT imagery. A small double sample of aircraft data made it possible to adjust a LANDSAT large area census. Terrain classification was improved by using multitemporal LANDSAT data. Waterfowl production was estimated, using remotely determined pond data, in conjunction with FWS estimates of breeding population. Relative waterfowl habitat quality was characterized on a section by section basis

Gaia 17bpi: An FU Ori Type Outburst

This is the author accepted manuscript. The final version is available from IOP Publishing via the DOI in this recordWe report on the source Gaia 17bpi and identify it as a new, ongoing FU Ori type outburst, associated with a young stellar object. The optical lightcurve from Gaia exhibited a 3.5 mag rise with the source appearing to plateau in mid/late 2018. Mid-infrared observations from NEOWISE also show a >3 mag rise that occurred in two stages, with the second one coincident with the optical brightening, and the first one preceding the optical brightening by ∼1.5 years. We model the outburst as having started between October and December of 2014. This wavelength-dependent aspect of young star accretion-driven outbursts has never been documented before. Both the mid-infrared and the optical colors of the object become bluer as the outburst proceeds. Optical spectroscopic characteristics in the outburst phase include: a GK-type absorption spectrum, strong wind/outflow in e.g. Mgb, NaD, Hα, K I, O I, and Ca II profiles, and detection of Li I 6707 ˚A. The infrared spectrum in the outburst phase is similar to that of an M-type spectrum, notably exhibiting prominent H2O and 12CO (2-0) bandhead absorption in the K-band, and likely He I wind in the Y-band. The new FU Ori source Gaia 17bpi is associated with a little-studied dark cloud in the galactic plane, located at a distance of 1.27 kpc.Leverhulme TrustScience and Technology Facilities Counci

Bounds on Lorentz and CPT Violation from the Earth-Ionosphere Cavity

Electromagnetic resonant cavities form the basis of many tests of Lorentz invariance involving photons. The effects of some forms of Lorentz violation scale with cavity size. We investigate possible signals of violations in the naturally occurring resonances formed in the Earth-ionosphere cavity. Comparison with observed resonances places the first terrestrial constraints on coefficients associated with dimension-three Lorentz-violating operators at the level of 10^{-20} GeV.Comment: 8 pages REVTe

Features of Muon Arrival Time Distributions of High Energy EAS at Large Distances From the Shower Axis

In view of the current efforts to extend the KASCADE experiment (KASCADE-Grande) for observations of Extensive Air Showers (EAS) of primary energies up to 1 EeV, the features of muon arrival time distributions and their correlations with other observable EAS quantities have been scrutinised on basis of high-energy EAS, simulated with the Monte Carlo code CORSIKA and using in general the QGSJET model as generator. Methodically various correlations of adequately defined arrival time parameters with other EAS parameters have been investigated by invoking non-parametric methods for the analysis of multivariate distributions, studying the classification and misclassification probabilities of various observable sets. It turns out that adding the arrival time information and the multiplicity of muons spanning the observed time distributions has distinct effects improving the mass discrimination. A further outcome of the studies is the feature that for the considered ranges of primary energies and of distances from the shower axis the discrimination power of global arrival time distributions referring to the arrival time of the shower core is only marginally enhanced as compared to local distributions referring to the arrival of the locally first muon.Comment: 24 pages, Journal Physics G accepte

Влияние облучения и отжига на термическую стабильность радиационных дефектов в кремнии

Описан отжиг А-центров, дивакансий, А-центров, модифицированных водородом, в n-Si (P ≈ 10^14 см^-3), в отсутствие и при наличии примеси платины, после облучения протонами с энергией 1,8 МэВ. Показано, что энергия активации отжига радиационных дефектов при взаимодействии с водородно-вакансионными дефектами уменьшается с 1,1 до 0,8 эВ при увеличении концентрации платины в кремнии, так как деформационные поля, создаваемые атомами платины, уменьшают энергию переориентации дефектов. Уточнено энергетическое положение в запрещенной зоне кремния донорного уровня А-центра (ЕV + 0,415 эВ) на основании известных данных о положении А-центра, модифицированного атомом углерода (ЕV + 0,38 эВ) или водорода (ЕV + 0,28 эВ).Описано відпал А-центрів, дивакансій, А-центрів, модифікованих воднем, у n-Si (P ≈ 10^14 см^-3), за відсутності та при наявності домішки платини, після опромінення протонами з енергією 1,8 МеВ. Показано, що енергія активації відпалу радіаційних дефектів при взаємодії з воднево-вакансійними дефектами зменшується від 1,1 до 0,8 еВ зі збільшенням концентрації платини в кремнії, оскільки деформаційні поля, які створюються атомами платини, зменшують енергію переорієнтації дефектів. Уточнено енергетичне положення у забороненій зоні кремнію донорного рівня А-центра (ЕV + 0,415 еВ), виходячи із відомих даних щодо положення А-центра, модифікованого атомом вуглецю (ЕV + 0,38 еВ) або водню (ЕV + 0,28 еВ).The annealing of A-centers, divacancies, A-centers modified by hydrogen was described for n-Si (P ≈ 10^14 cm^-3), with and without platinum dopants, after the irradiation by protons with energy 1.8 MeV. It was shown that the activation energy of annealing for radiation defects under their interaction with hydrogen-vacancy defects is decreased from 1.1 to 0.8 eV with the increasing of platinum concentration in silicon, because the deformation fields, creating by platinum atoms, decrease the energy of the defect re-orientation. In the forbidden zone of silicon the energy state for the donor level of A-center (ЕV + 0.415 eV) was specified based on the data about the position of A-center modified by the carbon atom (ЕV + 0.38 eV) or the hydrogen atom (ЕV + 0.28 eV)

Signals for Lorentz Violation in Post-Newtonian Gravity

The pure-gravity sector of the minimal Standard-Model Extension is studied in the limit of Riemann spacetime. A method is developed to extract the modified Einstein field equations in the limit of small metric fluctuations about the Minkowski vacuum, while allowing for the dynamics of the 20 independent coefficients for Lorentz violation. The linearized effective equations are solved to obtain the post-newtonian metric. The corresponding post-newtonian behavior of a perfect fluid is studied and applied to the gravitating many-body system. Illustrative examples of the methodology are provided using bumblebee models. The implications of the general theoretical results are studied for a variety of existing and proposed gravitational experiments, including lunar and satellite laser ranging, laboratory experiments with gravimeters and torsion pendula, measurements of the spin precession of orbiting gyroscopes, timing studies of signals from binary pulsars, and the classic tests involving the perihelion precession and the time delay of light. For each type of experiment considered, estimates of the attainable sensitivities are provided. Numerous effects of local Lorentz violation can be studied in existing or near-future experiments at sensitivities ranging from parts in 10^4 down to parts in 10^{15}.Comment: 46 pages two-column REVTeX, accepted in Physical Review