A Fully Depleted pn-Junction CCD for Infrared-, UV- and X- ray detection     

C. von Zanthier  H. Bräuninger  K. Dennerl  R. Hartmann  G. Hartner  H. Hippmann  A. Kaltenberger  E. Kastelic  W. Kink  N. Krause  N. Meidinger  G. Metzner  E. Pfeffermann  M. Popp  C. Reppin  J. Riedl  D. Stötter  L. Strüder  J. Trümper  W. Weber  D. Carathanassis  S. Engelhard  Th. Gebhart  D. Hauff  G. Lutz  R. H. Richter  H. Seitz  P. Solc  E. Biehler  H. Böttcher  E. Kendziorra  J. Krämer  B. Pflüger  R. Staubert  P. Holl  J. Kemmer  P. Lechner  B. Maier  H. Soltau  R. Stötter  E. Bihler 《Experimental Astronomy》1998,8(1):89-96

This paper describes the performance of the Fully Depleted pn-junction CCD (pn-CCD) system, developed for ESA's XMM-satellite mission for soft x-ray imaging and spectroscopy in the single photon counting mode in the 100 eV to 10 keV photon range. The 58 mm x 60 mm large pn-CCD array, designed and fabricated at the Semiconductor Lab (Halbleiterlabor) of the Max-Planck-Institut, uses pn-junctions for registers and as backside structure. This concept naturally enables full depletion of the detector volume independent of the silicon wafer's resistivity and thickness, and as such make it an efficient detector for the x-ray region and the infrared. For high detection efficiency in the soft x-ray region and UV, an ultrathin pn-CCD backside deadlayer has been realized. Each pn-CCD-channel is equipped with its own on-chip JFET amplifier which, in combination with the CAMEX-amplifier and multiplexing chip, facilitates parallel readout and fast data rate: the cooled pn-CCD system can be read out at a data rate up to 3 MHz with an electronic noise floor of ENC < 5 e-.  相似文献   

The influence of a stratified rheology on the flexural response of the lithosphere to (un)loading by extensional faulting   总被引：2，自引：0，他引：2  

M. ter Voorde  R. T. van Balen  G. Bertotti  & S. A. P. L. Cloetingh 《Geophysical Journal International》1998,134(3):721-735

We present a two-layered finite difference model for the flexural response of the lithosphere to extensional faulting. The model allows for three modes of flexure: (1) fully coupled, with the upper crust and mantle welded together by the lower crust; (2) fully decoupled, with the upper crust and mantle behaving as independent layers; and (3) partly decoupled, signifying that the response of the upper crust to small-wavelength loads is superimposed on the response of the entire lithosphere to long-wavelength loads. Which of these modes of flexure is to be expected depends on the rheology and especially the thermal state of the lithosphere. Coupled behaviour is related to a cold and strong lithosphere. The Baikal Rift Zone provides a typical example for this mode of flexure. A fully decoupled lithosphere is an exceptional case, related to anomalous high temperatures in the lower crust, and is observed in the Basin and Range province. The most common case is a partly decoupled lithosphere, with the degree of decoupling depending on the thickness and viscosity of the lower crust. This is inferred, for example, for the Bay of Biscay margin.  相似文献   

Modelling Spatial Patterns of Overbank Sedimentation on Embanked Floodplains   总被引：2，自引：0，他引：2  

Hans Middelkoop  & Marcel van der Perk 《Geografiska Annaler: Series A, Physical Geography》1998,80(2):95-109

This paper presents a GIS-based mathematical model for the simulation of floodplain sedimentation. The model comprises two components: (1) the existing hydrodynamic WAQUA model that calculates two-dimensional water flow patterns; and (2) the SEDIFLUX model that calculates deposition of sediment based on a simple mass balance concept with a limited number of model parameters. The models were applied to simulate floodplain sediment deposition over river reaches of several kilometres in length. The SEDIFLUX model has been calibrated and validated using interpolated raster maps of sediment deposition observed after the large magnitude December 1993 flood on the embanked floodplain of the lower river Rhine in the Netherlands. The model appeared to be an adequate tool to predict patterns of sediment deposition as the product of the complex interaction among river discharge and sediment concentration, floodplain topography, and the resulting water flow patterns during various discharge levels. In the investigated areas, the resulting annual average sedimentation rates varied between 0.5 mm/year and 4.0 mm/year. The role of the most important mechanisms governing the spatial patterns of overbank deposition, i.e. inundation frequency, sediment load, floodplain topography and its influence on the flow patterns over the floodplain, are discussed.  相似文献   

Observations and origin of Rayleigh-wave amplitude anomalies   总被引：1，自引：0，他引：1  

S. van der Lee 《Geophysical Journal International》1998,135(2):691-699

This is a report of observations of amplitude anomalies of fundamental-mode Rayleigh waves ( R 1) between periods of 17 and 100  s. The anomalies are with respect to amplitudes predicted by Rayleigh-wave excitation for a reference earth model and catalogued centroid earthquake source parameters, such as are used in large-scale waveform inversions. The observations indicate that the amplitude anomalies are consistent for nearby recordings of the same event, while there is no obvious relation between the observed anomalies and the paths travelled by the waves. This is in contrast to Rayleigh-wave phase anomalies, which are consistent for similar propagation paths, and hence form the input in many inversions for along-path structure. The observations in this paper show that a similar inversion of intermediate-period amplitude anomalies for along- and near-path structure is not warranted without eliminating source effects, since the amplitude anomalies are dominated by scattering off near-source earth structure and by possible uncertainties in the source parameters. Sensitivity kernels that take the coupling between the moment tensor and displacement field into account demonstrate that Rayleigh-wave amplitude sensitivity is largest near the source. This report argues that the interaction between source-radiated Rayleigh waves and near-source earth structure may not be ignored in amplitude inversion procedures.  相似文献   

Post-Variscan sedimentary record of the SW margin of the Bohemian massif: a review     

B. Schröder  H. Ahrendt  A. Peterek  K. Wemmer 《International Journal of Earth Sciences》1997,86(1):178-184

The late-Palaeozoic to Cenozoic stratigraphic and structural record of the southwestern margin of the Bohemian massif and its extension beneath the southward adjacent Molasse basin shows that it is controlled by a system of basement-involving faults which came into evidence during Stephanian– Autunian times and which were subsequently repeatedly reactivated. Thick Permo-Carboniferous clastics accumulated in fault-bounded transtensional basins aligned with the southwestern Bohemian border zone (SWBBZ). Following late-Autunian deformation of these basins, the SWBBZ was overstepped by late-Permian to Late Jurassic platform sediments, reflecting tectonic stability. During the Early Cretaceous the SWBBZ was strongly reactivated, causing disruption and erosion of its Mesozoic sedimentary cover. Sedimentation resumed in the area of the SWBBZ during late Early and Late Cretaceous with clastic influx from the Bohemian massif reflecting gradually increasing tectonic activity along the SWBBZ. During the Late Senonian and Paleocene transpressional deformations resulted in upthrusting of major basement blocks. In the Molasse basin such structures are sealed by transgressive Late Eocene marine strata. Mio-Pliocene uplift of the Bohemian massif, involving mild reactivation of the SWBBZ, is related to the development of the volcano-tectonic Eger zone. The structural configuration of the SWBBZ is largely the result of Late Senonian–Paleocene compressional intraplate tectonics which play a major role in the structural framework of the northern Alpine and Carpathian foreland.  相似文献   

Neogene fault activity and morphogenesis in the basement area north of the KTB drill site (Fichtelgebirge and Steinwald)     

A. Peterek  B. Schröder 《International Journal of Earth Sciences》1997,86(1):185-190

The Fichtelgebirge and Steinwald areas are situated at the western end of the Cenozoic Eger graben. Repeated Neogene fault activity and polyphase morphogenesis created a complex morphotectonic structure. Based on morphotectonic criteria three stages of tectonic activity can be determined: (a) late Oligocene to early Miocene; (b) middle-late Miocene; and (c) late Pliocene to early Pleistocene. Due to the Neogene tectonic movements, the pre-basaltic (preOligocene to Miocene) landscape has been differentially uplifted/downthrown and intensely modified by post-basaltic surface planation (HF). Broad paleovalleys (AT) of late Miocene to early Pliocene age and a system of Pliocene and Quaternary fluvial terraces and pediments (BT and ET) have been incised into the widespread HF relief elements. Due to repeated faulting and erosion, the stratigraphic record of Neogene sediments within the studied area is fragmentary.  相似文献   

Prediction of the occurrence of slope instability phenomenal through GIS-based hazard zonation   总被引：1，自引：0，他引：1  

C. J. van Westen  N. Rengers  M. T. J. Terlien  R. Soeters 《International Journal of Earth Sciences》1997,86(2):404-414

Slope instability hazard assessment is based on the analysis of the terrain conditions at sites where slope failures occurred in the past. For the analysis of the causative factors the application of geographic information systems (GIS) is an essential tool in the data analysis and subsequent hazard assessment. Three scale levels of hazard mapping are defined. A direct experience-driven mapping at reconnaissance level, a statistical approach to determine the causative factors in a quantitative susceptibility mapping and a methodology at large-scale making using of deterministic models.  相似文献   

A SVAT scheme for NO,NO2, and O3 — Model description and test results     

G. Kramm  N. Beier  T. Foken  H. Müller  P. Schröder  W. Seiler 《Meteorology and Atmospheric Physics》1996,61(1-2):89-106

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Macroscopic representation of structural geometry for simulating water and solute movement in dual-porosity media     

Horst H. Gerke  Martinus Th. van Genuchten 《Advances in water resources》1996,19(6):343-357

The structure of macroporous or aggregated soils and fractured rocks is generally so complex that it is impractical to measure the geometry at the microscale (i.e., the size and the shape of soil aggregates or rock matrix blocks, and the myriad of fissures or fractures), and use such data in geometry-dependent macroscale flow and transport models. This paper analyzes a first-order type dual-porosity model which contains a geometry-dependent coefficient, β, in the mass transfer term to macroscopically represent the size and shape of soil or rock matrix blocks. As a reference, one- and two-dimensional geometry-based diffusion models were used to simulate mass transport into and out of porous blocks of defined shapes. Estimates for β were obtained analytically for four different matrix block geometries. Values for β were also calculated by directly matching analytical solutions of the diffusion models for a number of selected matrix block geometries to results obtained with the first-order model assuming standard boundary conditions. Direct matching improved previous results for cylindrical macropore geometries, especially when relatively small ratios between the outer soil mantle and the radius of the inner cylinder were used. Results of our analysis show that β is closely related to the ratio of the effective surface area available for mass transfer, and the soil matrix volume normalized by the effective characteristic length of the matrix system. Using values of β obtained by direct matching, an empirical function is derived to estimate macroscopic geometry coefficients from medium properties which in principle are measurable. The method permits independent estimates of β, thus allowing the dual-porosity approach eventually to be applied to media with complex and mixed types of structural geometry.  相似文献   

Analytical Modeling of Effects of Application Frequency on Pesticide Concentrations in Wells   总被引：1，自引：0，他引：1  

W.H.J. Beltman  J.J.T.I. Boesten  S.E.A.T.M. van der  Zee J. J. Quist 《Ground water》1996,34(3):470-479

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