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291.
The ionic charge of solar energetic particles (SEP) as observed in interplanetary space is an important parameter for the
diagnostic of the plasma conditions at the source region and provides fundamental information about the acceleration and propagation
processes at the Sun and in interplanetary space. In this paper we review the new measurements of ionic charge states with
advanced instrumentation onboard the SAMPEX, SOHO, and ACE spacecraft that provide for the first time ionic charge measurements
over the wide energy range of ∼0.01 to 70 MeV/nuc (for Fe), and for many individual SEP events. These new measurements show
a strong energy dependence of the mean ionic charge of heavy ions, most pronounced for iron, indicating that the previous
interpretation of the mean ionic charge being solely related to the ambient plasma temperature was too simplistic. This energy
dependence, in combination with models on acceleration, charge stripping, and solar and interplanetary propagation, provides
constraints for the temperature, density, and acceleration time scales in the acceleration region. The comparison of the measurements
with model calculations shows that for impulsive events with a large increase of Q
Fe(E) at energies ≤1 MeV/nuc the acceleration occurs low in the corona, typically at altitudes ≤0.2 R
S
. 相似文献
292.
N. Tarcea T. Frosch P. Rösch M. Hilchenbach T. Stuffler S. Hofer H. Thiele R. Hochleitner J. Popp 《Space Science Reviews》2008,135(1-4):281-292
This paper introduces Raman spectroscopy and discusses various scenarios where it might be applied to in situ planetary missions. We demonstrate the extensive capabilities of Raman spectroscopy for planetary investigations and argue that this technique is essential for future planetary missions. 相似文献
293.
294.
Vytenis M. Vasyliūnas 《Space Science Reviews》2011,158(1):91-118
Many widely used methods for describing and understanding the magnetosphere are based on balance conditions for quasi-static
equilibrium (this is particularly true of the classical theory of magnetosphere/ionosphere coupling, which in addition presupposes
the equilibrium to be stable); they may therefore be of limited applicability for dealing with time-variable phenomena as
well as for determining cause-effect relations. The large-scale variability of the magnetosphere can be produced both by changing
external (solar-wind) conditions and by non-equilibrium internal dynamics. Its developments are governed by the basic equations
of physics, especially Maxwell’s equations combined with the unique constraints of large-scale plasma; the requirement of
charge quasi-neutrality constrains the electric field to be determined by plasma dynamics (generalized Ohm’s law) and the
electric current to match the existing curl of the magnetic field. The structure and dynamics of the ionosphere/magnetosphere/solar-wind
system can then be described in terms of three interrelated processes: (1) stress equilibrium and disequilibrium, (2) magnetic
flux transport, (3) energy conversion and dissipation. This provides a framework for a unified formulation of settled as well
as of controversial issues concerning, e.g., magnetospheric substorms and magnetic storms. 相似文献
295.
296.
297.
M. Kästner P. Köpke H. Quenzel 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1982,2(5):119-121
The optical depth of Saharan dustclouds (a component of the radiation budget), which can be clearly seen in satellite images taken over the Atlantic, can be determined from the Meteosat VIS-data. ‘Favourable angles’ between sun, observed point and satellite are chosen so that the optical depth is determined with an inaccuracy of only about 20%.We present several clouds, their change over time, and some of their other interesting features. The results are discussed. 相似文献
298.
M. Van Der Klis 《Space Science Reviews》1993,62(1-2):173-202
The observational information on X-ray binaries that was collected with the 80 cm2 auxiliary X-ray detector onboard the COS-B gamma-ray satellite is reviewed. The results illustrate that in the study of X-ray binaries observations of long duration are extremely effective, even when using a small instrument. 相似文献
299.
B. Ehmann L. Balázs É. Fülöp R. Hargitai P. Kabai B. Péley T. Pólya A. Vargha J. László 《Acta Astronautica》2011,68(9-10):1560-1566
This paper is about a pilot application of narrative psychological content analysis in the psychological status monitoring of Crew 71 of a space analog simulation environment, the Mars Desert Research Station (MDRS). Both the method and its theoretical framework, Scientific Narrative Psychology, are original developments by Hungarian psychologists [5] (László, 2008). The software was NooJ, a multilingual linguistic development environment [11] (Silberztein, 2008). Three measures were conceptualized and assessed: emotional status, team spirit and subjective physical comfort. The results showed the patterns of these three measures on a daily basis at group level, and allowed for detecting individual differences as well. The method is adaptable to languages involved in space psychology, e.g. Russian, French and German in addition to English. 相似文献
300.
C. Fröhlich J.A. Eddy 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》1984,4(8):121-124
We compile measurements of the total solar irradiance So made in the period 1967 to 1983 from balloons, rockets, and spacecrafts. These data, when corrected for atmospheric and calibration differences, suggest a systematic increase in So of about 0.025% per year. In 1979 and after the ACRIM/SMM and the ERB/NIMBUS data reveal a systematic decrease of about the same magnitude. The period of the early apparent increase embraces a full solar activity cycle of 11 years: hence the effect cannot be that of simple sunspot blocking. This trend of a slow increase followed by a similar decrease is compared with solar diameter measurements obtained from daily meridian transit timings of the Sun made during the same period at the Royal Greenwich Observatory and at the U.S. Naval Observatory. We find in both of these data sets an apparent increase in solar diameter of about 0.03″arc per year during the period of increasing solar irradiance and a weaker suggestion of a similar, subsequent decline. If the apparent trends in diameter and luminosity are real they allow us to estimate the empirical relationship between the two quantities. For this period we find W=ΔlogR/ΔlogL=0.078±0.026. 相似文献