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51.
M. Lemoine-Goumard F. Aharonian D. Berge B. Degrange D. Hauser N. Komin O. Reimer U. Schwanke 《Astrophysics and Space Science》2007,309(1-4):379-384
In 2004 and 2005, the shell-type supernova remnants RX J1713.7–3946 and RX J0852.0–4622 were observed and detected with the
complete H.E.S.S. array, a system of four Imaging Cherenkov Telescopes located in Namibia and dedicated to the observations
of γ-rays above 100 GeV. The energy spectra of these two sources have been measured over a wide energy range and revealed an integral
flux above 1 TeV similar to that of the Crab Nebula. Their morphologies were resolved with high accuracy with H.E.S.S. and
exhibit a striking correlation with the X-ray images, thereby pioneering a technique of unambiguously identifying spatially
extended γ-ray sources. The results of the observations will be presented. Similarities and differences between these two sources will
be pointed out as well as possible implications.
M. Lemoine-Goumard, F. Aharonian, D. Berge, B. Degrange, D. Hauser, N. Komin, O. Reimer, U. Schwanke for the H.E.S.S. Collaboration 相似文献
52.
Prof. Dr. Otto Förtsch Dr. Eberhard Schmedes 《International Journal of Earth Sciences》1976,65(1):748-755
Zusammenfassung Mit Hilfe von vier seismologischen Stationen in Bad Reichenhall (BHG), Garmisch-Partenkirchen (GAP), Innsbruck (IBK) und Schlegeis (SCE) werden Kleinbeben im nördlichen Teil der Geotraverse I a beobachtet, die vom internationalen Erdbebendienst nicht registriert werden. In der Zeit von Januar 1972 bis Januar 1975 wurden etwa 200 Beben mit Herden im Untersuchungsgebiet aufgezeichnet. Seit März 1973 konnten die Epizentren von etwa 30 Beben bestimmt werden. Bei zwei Beben wurden makroseismische Untersuchungen durchgeführt. Es wurde die zeitliche und räumliche Verteilung der Beben bestimmt, um daraus auf rezente Bewegungen und Bewegungszonen in diesem Teil der Ostalpen zu schließen.
In the northern part of the Geotraverse I a microearthquakes are investigated with four seismological stations situated in Bad Reichenhall (BHG), Garmisch-Partenkirchen (GAP), Innsbruck (IBK) and Schlegeis (SCE). Between January 1972 and January 1975 about 200 earthquakes were recorded with origins within the region under investigation. Since March 1973 the epicenters of about 30 earthquakes were determined. For two events macroseismic investigations were carried out. A seismicity map shows the nowadays mobile regions in this part of the eastern Alps.
Résumé Grâce à quatre stations séismologiques situées à Bad Reichenhall (BHG), Garmisch-Partenkirchen (GAP), Innsbruck (IBK) et Schlegeis (SCE) environ 200 tremblements de terre ont été enrigistrés dans la région nord de la Geotraverse I a entre janvier 1972 et janvier 1975. Depuis mars 1973 les épicentres de 30 tremblements de terre ont été déterminés. A deux reprises des recherches macroséismiques ont eu lieu. La carte de la séismicité montre les régions actuellement actives dans cette partie des Alpes orientales.
: , -, — I , . 1972 1975 200 . . , .相似文献
53.
In an inversion-capped planetary boundary layer (PBL), the structure of the turbulent fluxes as well as the height of the inversion are determined by the interaction of turbulent mixing in the PBL, large-scale subsidence above the PBL and radiational cooling. Here the sensitivity of the inversion height and of the turbulent fluxes due to radiational processes is investigated with the aid of a three-layered model for a well mixed PBL. For an example of the Trade-Wind region, the inversion height (i.e., the difference between surface pressure and pressure at the inversion level) varies between 46 and 257 mb and the surface flux of moist static energy between 417 and 99 W m-2, if the (mean) radiative net flux divergence for both the inversion and the well-mixed layer is changed over a reasonable range of values. None of the parameterization schemes existing in the literature is able to describe these radiational effects in an appropriate way. This is due to the fact that these parameterizations are either not or not flexibly enough linked to the thermodynamical model parameter. Therefore the demand for an adequate parameterization of the radiational influence in a well-mixed PBL under a subsidence inversion is obvious. 相似文献
54.
Eberhard Schaller 《Boundary-Layer Meteorology》1977,11(3):329-354
The energy-budget concept is used together with a high resolution spectral radiation model to study the time and height variation of the sensible heat flux and of the eddy thermal diffusivity for an actual case up to 50 m above ground. A data set of 32 h is chosen for this study. Time-height cross-sections of the local enthalpy changes, and the radiative and the sensible heat flux divergences are presented, which show the interaction of the two energy fluxes. It can be seen, for example, that during the transient hours from night to day the sensible heat flux divergence plays an outstanding role in the warming of the atmosphere, while during the clear night radiative cooling exceeds the cooling caused by the sensible heat flux. For the layer under consideration (0-50 m) a constancy of the sensible heat flux within 10% is obtained for seven hours only, namely for the time around noon and in the early afternoon. Selected night-time profiles of the thermal diffusivity are shown, which have their maximum below 48.3 m.The accuracy of the energy-budget method is studied in detail. The tests show that a high accuracy, with errors even less than 10% for some hours, can be expected, if special micrometeorological studies are made during the field phase and a layer depth of 50 cm or less is used in the radiation model. 相似文献
55.
Prof. Dr. Eberhard Klitzsch 《International Journal of Earth Sciences》1978,67(2):509-520
Zusammenfassung In einem auf die Klärung stratigraphischer, fazieller, paläogeographischer, hydrogeologischer und paläoklimatischer Fragen ausgerichteten Forschungsprogramm wird eine Bearbeitung Südwest-Ägyptens durchgeführt. Neben dem Nachweis einer altpaläozoischen — vermutlich ordovizischen — Vereisung und jüngerer, mariner paläozoischer Schichten erfolgte bisher eine Gliederung der ehemaligen Nubischen Serie dieses Gebietes in mehrere marine und kontinentale Sedimentationszyklen von jurassischem bis oberkretazischem Alter. Eine detaillierte geologische Karte von Südwest-Ägypten ist in Vorbereitung.
First results of geological research in Southwestern Egypt are presented, which are part of a programme dedicated to stratigraphical, sedimentological, paleogeographical and hydro geological as well as paleoclimatical questions. The research programme is sponsored by Deutsche Forschungsgemeinschaft, it is carried out in cooperation with the Academy of Science of Egypt and it is backed by Continental Oil Company.Apart from the proof of an Early Paleozoic glaciation of probably Ordovician age, marine sediments of younger Paleozoic ages were found. The former Nubian Sandstone was subdivided into several formations of shallow marine to continental origin of Jurassic to Late Cretaceous age. A detailed geological map of Southwestern Egypt is under preparation.
Résumé Les premiers résultats de recherche géologique dans le Sud-Ouest de l'Egypte sont présentés; ils font partie d'un programme d'étude des questions stratigraphiques, sédimentologiques, paléogéographiques, hydrogéologiques et paléoclimatiques. Ce programme est subventionné par la Deutsche Forschungsgemeinschaft, réalisé en coopération avec l'Académie des Sciences d'Egypte et assisté par Conoco.Outre la preuve d'une glaciation d'âge paléozoique — probablement ordovicien — et de sédiments marins paléozoiques plus jeunes, une division de l'ancien «Grès Nubie» de cette région en plusieurs cycles de sédimentation marine et continentale du Jurassique au Crétacé supérieur fut effectuée. Une carte géologique détaillée du Sud-Ouest de l'Egypte est en préparation.
, , , . -, - , , . - .相似文献
56.
Eberhard?FahrbachEmail author Mario?Hoppema Gerd?Rohardt Michael?Schr?der Andreas?Wisotzki 《Ocean Dynamics》2004,54(1):77-91
Data from cruises between 1989 and 2003 with FS Polarstern were used to construct section-wide potential temperature and salinity time series of the main water masses in the Weddell Gyre. In tandem with these CTD data, two time series between 1989 and 1995 are presented from moored instruments in the central Weddell Sea. The regional and methodological consistency of the dataset allows us to quantify variations which are not visible in less homogeneous datasets. The data reveal significant temperature and salinity variations of the Warm Deep Water and the Weddell Sea Bottom Water on a decadal time scale. The longest time series were obtained at the prime meridian. Here warming is observed in the Warm Deep Water from 1992 to 1998 followed by cooling. In the Weddell Sea proper, measurements of instruments moored in the Weddell Sea Bottom Water layer recorded a temperature increase over 6 years at a rate of 0.01 °C a–1. After the mooring period, CTD casts in 1998 point to a weakening of the trend. The warming trend in the bottom water occurs over most of the Weddell Sea, as detected in the additional CTD surveys. The variations are close to the detection level in the voluminous Weddell Sea Deep Water. The initial warming trend of the Warm Deep Water is consistent with warming trends reported in literature of subsurface waters of the Antarctic Circumpolar Current. The reversal of the trend in the Weddell Sea seems to be related to variations of the atmospheric conditions which can affect both the intrusion of Circumpolar Deep Water from the north and the circulation of the Weddell Gyre. Because the Warm Deep Water is the major source water for the formation of deep and bottom water in the Weddell Sea, it is suggested that its increase in temperature and salinity is likely to at least partly cause the variations which were observed in the bottom water.Responsible Editor: Jörg-Olaf Wolff 相似文献
57.
The evolution of carbonate groundwaters may occur in a so-called open or closed system or under conditions between the extremes. In order to distinguish between the cases the chemistry of the water and the carbon isotope composition of the dissolved carbonate, the carbonate rock and the soil CO2 of the recharge area must be known. Model calculations based on measurements of the above parameters show that ground-waters in the “Schwäbische Alb”, Federal Republic of Germany, are evolved essentially under closed-system conditions. The average measured carbon isotope composition of the water is δ 13C = ?13.7%0 vs. calculated values of δ 13C = ?13.5%0 and δ 13C = ?18.5%0 assuming a closed and an open system, respectively. In model calculations for closed-system conditions the origin of sulfate ions has to be considered. 相似文献
58.
59.
60.
Seasonal variability of the Antarctic Coastal Current and its driving mechanisms in the Weddell Sea 总被引:2,自引:0,他引:2
Ismael Núez-Riboni Eberhard Fahrbach 《Deep Sea Research Part I: Oceanographic Research Papers》2009,56(11):1927-1941
Insight into the dynamics of the Antarctic Coastal Current (ACoC) is achieved by quantifying the contributions of its driving mechanisms to the seasonal variability of its barotropic and baroclinic components. These mechanisms are sought out in the local wind, the sea-ice concentration, wind curl of the Weddell Gyre (Sverdrup transport) and the thermohaline forcing related to warming/cooling and ice melting and freezing. These driving mechanisms induce most of the seasonal variability of both the barotropic and baroclinic components of the ACoC by deepening the pycnocline towards the coast and sharpening the baroclinic profile following thermal wind balance. The resulting coastal current has mainly a barotropic transport (82%) and a major annual cycle, which explains 37% of this component's variability (tides and other high-frequency events generate 40%). The wind contributes with 58% of the seasonal variability of the barotropic component and 23% of the baroclinic; the sea-ice concentration contributes with 8% and 18%, respectively; Sverdrup transport with 4% and 30% and the thermohaline forcing with 30% and 29%. The results of this study are obtained with analysis of fifteen CTD sections (potential density and geostrophic velocities) of RV-Polarstern obtained between 1992 and 2005, as well as composite, spectral and harmonic analyses of 9 years of time series from moored instruments (current speed and temperature), wind speed, atmospheric pressure and sea-ice concentration of satellite imagery. 相似文献