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551.
Kjell Rönnmark 《Planetary and Space Science》1975,23(9):1337-1339
Pitch-angle diffusion of ring current protons is investigated, assuming that the scattering is caused by resonant interaction with electrostatic ion loss-cone waves. Bounce averaged diffusion coefficients are presented for different wave energy distributions. It is found that wave amplitudes about 1 mV/m are required to give strong diffusion of protons with average energy. 相似文献
552.
We report on results from photographic observations of photospheric oscillations as a function of depth. Using rms-values and power-spectra from shifts of entire line-profiles, we find qualitatively an increase of the velocity-amplitude with increasing height. We get more quantitative informations by comparing measured asymmetries of line-profiles with calculated ones derived from Voigt-functions containing a depth dependent velocity-field.We find the scale-height H
0 of photospheric velocity oscillations to be 930±100 km. This result is to be compared with H
0 = 1100±200 km obtained by Canfield (1976), who used velocity weighting functions of the line centres.Further, we show that a general observed line asymmetry of medium strong lines (c-shape) does not depend on the phase of oscillations.Mitt. aus dem Kiepenheuer-Institut Nr. 178. 相似文献
553.
From photographic recordings of some hundred bright Ca+-network cells on the solar disk we find evidence for a smaller size of polar cells as compared to equatorial cells by a factor of about 0.9. We do not find an indication of a dependence of the structure of the cells on the heliographic position. 相似文献
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A 14C-dated magnetostratigraphy of absolute declination and inclination between 12500 and 10000 14C yr BP was recently developed for southern Sweden. Recently also the Swedish geochronological time-scale, based on c. 11 500 annually deposited clay-varves, was connected with the present. It should therefore be possible to compare the two chronologies with a reliable magnetostratigraphic record in an appropriate clay-varve section. We have found such a site within the Middle Swedish end-moraine zone. Statistical correlations between the two independently dated time-scales suggest that at 10500–10200 14Cy r BP the varve chronology exceeds the 14C chronology by the order of 500-600 varve yr. Other correlations indicate that the difference between the two chronologies was less at 11000 14C yr BP, and further correlations between the time-scales at 12000 14C yr BP suggest that the difference between the chronologies increased steadily from 12000 to 10000 14C yr BP. If these correlations are correct they imply that the 14C production rate increased steadily during the Late Weichselian. 相似文献
557.
A. Böhme 《Solar physics》1972,25(2):478-488
The spectral behaviour of a group of broad-band continua at metre and decametre waves is discussed. These broad-band continua are polarized in the extraordinary mode and occur during the explosive phase of some strong flares. The time behaviour of the broad-band continua and of the moving type IV bursts was already compared in a previous paper (Böhme, 1972). It is pointed out in the present paper that the broad-band continua differ from the moving type IV bursts not only regarding their time behaviour but also with reference to some spectral characteristics. Moreover, the broad-band continua differ from the moving type IV bursts by their close relation to proton events. It can be concluded that the high-energy protons are accelerated in different steps. An important secondary acceleration mechanism acts above the emission level of the type IV bursts. 相似文献
558.
Rosine Lallement Bertaux Jean-Loup Karöly Szegö Szilvia Nemeth 《Earth, Moon, and Planets》2002,90(1-4):67-76
For a few months around perihelion, thecentral part of the Hale–Bopp hydrogencloud has been optically thick to thesolar Lyα
radiation, and hassignificantly reduced the solar flux availablefor the resonance glow of interstellarhydrogen beyond the
comet. This shadowing effecton the interstellar gas is the first everobserved comet shadow. It is modeled andcompared with
SWAN observations. Shadowmodelling will help to constrain the cometwater production and radiative transfer effectsin the interstellar
ionisation cavity. 相似文献
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