Many-Body Theory Calculations of Positron Scattering and Annihilation in H2_2, N2_2 and CH4_4

The recently developed ab initio many-body theory of positron molecule binding [J. Hofierka et al., Nature, 606, 688 (2022)] is combined with the shifted pseudostates method [A. R. Swann and G. F. Gribakin, Phys. Rev. A 101, 022702 (2020)] to calculate positron scattering and annihilation rates on small molecules, namely H$_2$, N$_2$ and CH$_4$. The important effects of positron-molecule correlations are delineated. The method provides uniformly good results for annihilation rates on all the targets, from the simplest (H$_2$, for which only a sole previous calculation agrees with experiment), to larger targets, where high-quality calculations have not been available.Comment: Main text and Supplemental Materia

An objective method for the production of isopach maps and implications for the estimation of tephra deposit volumes and their uncertainties

Characterization of explosive volcanic eruptive processes from interpretation of deposits is a key for assessing volcanic hazard and risk, particularly for infrequent large explosive eruptions and those whose deposits are transient in the geological record. While eruption size—determined by measurement and interpretation of tephra fall deposits—is of particular importance, uncertainties for such measurements and volume estimates are rarely presented. Here, tephra volume estimates are derived from isopach maps produced by modeling raw thickness data as cubic B-spline curves under tension. Isopachs are objectively determined in relation to original data and enable limitations in volume estimates from published maps to be investigated. The eruption volumes derived using spline isopachs differ from selected published estimates by 15–40 %, reflecting uncertainties in the volume estimation process. The formalized analysis enables identification of sources of uncertainty; eruptive volume uncertainties (>30 %) are much greater than thickness measurement uncertainties (~10 %). The number of measurements is a key factor in volume estimate uncertainty, regardless of method utilized for isopach production. Deposits processed using the cubic B-spline method are well described by 60 measurements distributed across each deposit; however, this figure is deposit and distribution dependent, increasing for geometrically complex deposits, such as those exhibiting bilobate dispersion. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s00445-015-0942-y) contains supplementary material, which is available to authorized users

Post-eruptive flooding of Santorini caldera and implications for tsunami generation

Caldera-forming eruptions of island volcanoes generate tsunamis by the interaction of different eruptive phenomena with the sea. Such tsunamis are a major hazard, but forward models of their impacts are limited by poor understanding of source mechanisms. The caldera-forming eruption of Santorini in the Late Bronze Age is known to have been tsunamigenic, and caldera collapse has been proposed as a mechanism. Here, we present bathymetric and seismic evidence showing that the caldera was not open to the sea during the main phase of the eruption, but was flooded once the eruption had finished. Inflow of water and associated landsliding cut a deep, 2.0-2.5 km(3), submarine channel, thus filling the caldera in less than a couple of days. If, as at most such volcanoes, caldera collapse occurred syn-eruptively, then it cannot have generated tsunamis. Entry of pyroclastic flows into the sea, combined with slumping of submarine pyroclastic accumulations, were the main mechanisms of tsunami production

Data for: Physically-based land surface temperature modeling in urban areas using a 3-D city model and multispectral satellite data

lst.stefan-boltzman.sh - GRASS GIS shellscrip

Data for: Physically-based land surface temperature modeling in urban areas using a 3-D city model and multispectral satellite data

lst.stefan-boltzman.sh - GRASS GIS shellscriptTHIS DATASET IS ARCHIVED AT DANS/EASY, BUT NOT ACCESSIBLE HERE. TO VIEW A LIST OF FILES AND ACCESS THE FILES IN THIS DATASET CLICK ON THE DOI-LINK ABOV

Szczegółowe rozwiązanie trójwymiarowego wektora odkształcenia opisującego osiadanie terenu. Studium przypadku: nieczynna kopalnia magnezytu Kosice-Bankov, Słowacja

Mining activity influence on the environment belongs to the most negative industrial influences. Land subsidence can be a consequence of many geotectonic processes as well as due to anthropogenic interference with rock massif in part or whole landscape. Mine subsidence on the surface can be a result of many deep underground mining activities. The presented study offers the theory to the specific case of the deformation vectors solution in a case of disruption of the data homogeneity of the geodetic network structure in the monitoring station during periodical measurements in mine subsidence. The theory of the specific solution of the deformation vector was developed for the mine subsidence at the Košice-Bankov abandoned magnesite mine near the city of Košice in east Slovakia. The outputs from the deformation survey were implemented into Geographic Information System (GIS) applications to a process of gradual reclamation of whole mining landscape around the magnesite mine. After completion of the mining operations and liquidation of the mine company it was necessary to determine the exact edges of the Košice-Bankov mine subsidence with the zones of residual ground motion in order to implement a comprehensive reclamation of the devastated mining landscape. Requirement of knowledge about stability of the former mine subsidence was necessary for starting the reclamation works. Outputs from the presented specific solutions of the deformation vectors confirmed the multi-year stability of the mine subsidence in the area of interest. Some numerical and graphical results from the deformation vectors survey in the Košice-Bankov abandoned magnesite mine are presented. The obtained results were transformed into GIS for the needs of the self-government of the city of Košice to the implementation of the reclamation works in the Košice-Bankov mining area.Górnictwo pozostaje tą dziedziną działalności człowieka której wpływ na środowisko naturalne jest najbardziej niekorzystny. Osiadanie terenu może być skutkiem różnorakich procesów tektonicznych, a także działalności człowieka i jej ingerencji w integralność górotworu i krajobrazu w terenie. Osiadanie gruntu na powierzchni ponad kopalnią jest najczęściej skutkiem prowadzonego pod ziemią wydobycia. W pracy tej przedstawiono teorię mającą zastosowanie do szczególnego przypadku rozwiązania wektora odkształcenia w przypadku zaburzenia jednorodności sieci geodezyjnej i braku danych dla stacji monitoringu dokonującej okresowych pomiarów wielkości osiadania. Teoria mająca zastosowanie do szczególnego rozwiązania wektora odkształcenia opracowana została w trakcie badania przypadku nieczynnej kopalni magnezytu Kosice-Bankov, znajdującej się w pobliżu miasta Koszyce, we wschodniej Słowacji. Dane wyjściowe z pomiarów odkształcenia zostały zaimplementowane w aplikacji GIS (Geographic Information System) w celu opracowania programu całościowej rekultywacji terenu wokół dawnej kopalni magnezytu. Po zakończeniu działalności górniczej i likwidacji kopalni konieczne było wyznaczenie dokładnych granic niecki osiadania w rejonie kopalni Kosice-Bankov, wraz ze strefami w których odnotowuje się rezydualne ruchy gruntów, w celu opracowania całościowego projektu rekultywacji terenu zniszczonego przez działalność górniczą. Przed rozpoczęciem prac nad rekultywacją terenu konieczne było uzyskanie wiedzy o stabilności procesu i zakresie osiadania terenu ponad kopalnią. Wyniki uzyskane dzięki zastosowaniu szczegółowego rozwiązania wektora odkształcenia potwierdziły wieloletnią stabilizację procesu osiadania terenu na badanym obszarze. Przedstawiono rezultaty procedur numerycznych i wyniki w postaci graficznej rozwiązania wektora odkształcenia dla nieczynnej kopalni magnezytu Kosice-Bankov. Otrzymane wyniki wprowadzono następnie do bazy GIS na użytek władz lokalnych w mieście Koszyce, by umożliwić rozpoczęcie prac nad skuteczną rekultywacją terenów pogórniczych w rejonie kopalni Koszyce-Bankov

HIGH-RESOLUTION URBAN GREENERY MAPPING FOR MICRO-CLIMATE MODELLING BASED ON 3D CITY MODELS

Urban greenery has various positive micro-climate effects including mitigation of heat islands. The primary root of heat islands in cities is in absorption of solar radiation by the mass of building structures, roads and other solid materials. The absorbed heat is subsequently re-radiated into the surroundings and increases ambient temperatures. The vegetation can stop and absorb most of incoming solar radiation mostly via the photosynthesis and evapotranspiration process. However, vegetation in mild climate of Europe manifests considerable annual seasonality which can also contribute to the seasonal change in the cooling effect of the vegetation on the urban climate. Modern methods of high-resolution mapping and new generations of sensors have brought opportunity to record the dynamics of urban greenery in a high resolution in spatial, spectral, and temporal domains. In this paper, we use the case study of the city of Košice in Eastern Slovakia to demonstrate the methodology of 3D mapping and modelling the urban greenery during one vegetation season in 2016. The purpose of this monitoring is to capture 3D effects of urban greenery on spatial distribution of solar radiation in urban environment. Terrestrial laser scanning was conducted on four selected sites within Košice in ultra-high spatial resolution. The entire study area, which included these four smaller sites, comprised 4 km2 of the central part of the city was flown within a single airborne lidar and photogrammetric mission to capture the upper parts of buildings and vegetation. The acquired airborne data were used to generate a 3D city model and the time series of terrestrial lidar data were integrated with the 3D city model. The results show that the terrestrial and airborne laser scanning techniques can be effectively used to monitor seasonal changes in foliage of trees in order to assess the transmissivity of the canopy for microclimate modelling