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Wentzel  Donat G. 《Solar physics》1997,175(1):175-189
Solar Physics - What are the observational effects if type I bursts are deflected by lower-hybrid waves? The deflection creates an elliptical radio mirage, with the direct source at one end of the...  相似文献   
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Upgrading the Earthquake Catalog of Switzerland (ECOS) included revising the earthquake of 1720. This change has major importance for history and seismology.Although that quake has been the subject of several publications, none was based on critical methods. This re-evaluation of the event is built upon a new and more reliable database established after investigating archives and libraries. Using data from such historical sources, we assigned new site intensities, adopting the criteria established by the European macroseismic scale EMS 98 (Grünthal, 1998).We discovered that the event had been assigned an overestimated intensity, due to interpretation errors in former earthquake catalogs and compilations. We recommend reducing the intensity from I0= VIII to I0= VI (EMS 98). The moment magnitude is given as MW= 4.6. Since the event had been considered the largest for its respective area, downgrading it now will influence the seismic hazard assessment for this region.  相似文献   
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This report of the Swiss Seismological Service summarizes the seismic activity in Switzerland and surrounding regions during 2006. During this period, 572 earthquakes and 91 quarry blasts were detected and located in the region under consideration. Of these earthquakes, two occurred in conjunction with the construction of the new Gotthard railway tunnel and 165 were induced artificially by the stimulation of a proposed geothermal reservoir beneath the city of Basel. With 20 events with M L ≥ 2.5, five of which were artificially induced, the seismic activity in the year 2006 was far below the average over the previous 31 years. Nevertheless, six events were felt by the public, most prominently the strongest of the induced Basel events (M L 3.4), which caused some non-structural building damage. Noteworthy are also the two earthquakes near Cortaillod (M L 3.2), on the shore of Lake Neuchatel, and in Val Mora (M L 3.5), between the Engadin and Val Müstair, as well as the 42 aftershocks of the M L 4.9 Vallorcine earthquake, between Martigny and Chamonix, of September 2005. Editorial handling: Stefan Bucher  相似文献   
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Alfvén waves are generated easily in many cosmic plasmas, but they possess no linear damping mechanism since they are not compressive. The most prominent nonlinear damping occurs when one Alfvén wave decays into another plus a slow magnetosonic wave, or two Alfvén waves combine into one fast magnetosonic wave; the resulting magnetosonic waves can then be dissipated. The nonlinear coupling rates are presented, with special emphasis on the astrophysically important case of sound speed Alfvén speed. Streaming cosmic rays generate Alfvén waves moving in the direction of streaming, but they reabsorb the backward moving waves then produced by wave decay. The possible steady states for this system of cosmic rays and Alfvén waves turn out to be highly restricted.Supported by NSF grant GP-15218.  相似文献   
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I extend a previous paper which argued that Alfvén waves traveling up a large coronal loop may heat this loop at the top and increase its visibility. This heating is now evaluated more completely, taking into account the changes along the loop in field strength, gas density and flux of waves. The location and efficiency of the heating depend very non-linearly on the intensity of the waves, which allows rapid changes in the visibility of a loop. Observational and theoretical conditions for the applicability of the theory are summarized. Alfvén waves preferentially heat the upper portions of coronal helmets, but a measurable excess temperature on a loop requires somewhat implausibly high wave fluxes. Radiation losses from low-lying loops with strong magnetic fields cannot be explained without modifying the theory.The National Center for Atmospheric Research is sponsored by the National Science Foundation.  相似文献   
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