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821.
822.
Solar proton events recorded in the stratosphere during cosmic ray balloon observations in 1957–2008
G.A. Bazilevskaya V.S. MakhmutovY.I. Stozhkov A.K. SvirzhevskayaN.S. Svirzhevsky 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2010
Long-term balloon observations have been performed by the Lebedev Physical Institute since 1957 up to the present time. The observations are taken several times a week at the polar and mid latitudes and allow us to study dynamics of galactic and solar cosmic ray as well as secondary particle fluxes in the atmosphere and in the near-Earth space. Solar energetic particles (120) – mostly protons – (SEP) events with >100 MeV proton intensity above 1 cm−2 s−1 s−1 were recorded during 1958–2006. Before the advent of the SEP monitoring on spacecraft these results constituted the only homogeneous series of >100 MeV SEP events. The SEP intensities and energy spectra inferred from the Lebedev Physical Institute observations are consistent with the results taken in the adjacent energy intervals by the spacecraft and neutron monitors. Joint consideration of the SEP events series recorded by balloons and by neutron monitors during solar cycles 20–23 makes it possible to restore the probable number of events in solar cycle 19, which was not properly covered by observations. Some correlation was found between duration of SEP event production in a solar cycle and sunspot cycle characteristics. 相似文献
823.
The International Institute of Space Commerce (IISC) held a workshop on the influence of the financial crisis on the space sector in Douglas, Isle of Man from 18 to 19 November 2009. A number of experts presented their views on this topic. A summary of their generally upbeat findings are presented below. 相似文献
824.
An analysis of enhancements in the fluxes of electrons with energies above 300 keV registered onboard of the Coronas-F satellite in the polar regions at the boundary of the outer radiation belt is performed. Cases are revealed when the increases
in question were observed consequently during multiple crossings of the outer radiation belt boundary. Localization of the
revealed events relative to the auroral oval using the data of almost simultaneous observations of electrons with energies
of 0.1–10 keV on the Meteor-3M satellite and OVATION model is studied. It is shown that almost all studied increases in relativistic electrons are localized
at latitudes of the auroral oval. Various mechanisms which could cause the observed increases are discussed, as well as a
possibility of formation of local traps of energetic particles in the high-latitude magnetosphere. 相似文献
825.
A. V. Rodin N. A. Evdokimova R. O. Kuzmin A. A. Fedorova O. I. Korablev J. -P. Bibring 《Cosmic Research》2010,48(2):150-156
Channel C of the orbital hyperspectrometer OMEGA onboard Mars Express spacecraft has delivered data on the distribution and seasonal variability of water ice spectral features at 1.25, 1.5, 2.0
μm, based on which one may conclude about the thickness of ice coverage and microstructure of the upper, optically active
ice layer on the Martian surface. Data covering polar regions during spring-to-summer periods of both hemispheres have been
analyzed. Microstructure of the North polar cap, as well as the residual frost deposits of the seasonal South polar cap, have
revealed remarkable zonal variations with regularly located maxima. Based on the comparison with the atmospheric general circulation
model results, it has been proposed that these variations result from the impact of mesoscale inertial waves in the circumpolar
vortex on water exchange processes between the atmosphere and planetary surface. 相似文献
826.
I. S. Akhmed’yanov 《Russian Aeronautics (Iz VUZ)》2010,53(1):102-107
The application of the numerical quadrature method to analyzing the shells of revolution under reversely symmetrical loading
is considered. 相似文献
827.
828.
M. Guainazzi I. Barbarisi S. Bianchi P. Osuna J. Salgado 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008,41(12):1998-2001
High-energy, high-resolution in the spatial and energy domains is crucial to derive the geometrical distribution and the physical properties of gas and dust surrounding Active Galactic Nuclei (AGN). These are, in turn, basic ingredients of any serious attempt to build an AGN structure model. We present in this paper CIELO-AGN, the first catalogue of ionized emission lines detected in the soft X-ray spectra of a sample of 69 nearby obscured AGN. This catalogue has been implemented according to an IVOA data model, and can be accessed through VO-compatible applications. 相似文献
829.
L.I. Dorman O.A. Danilova N. Iucci M. Parisi N.G. Ptitsyna M.I. Tyasto G. Villoresi 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008
In this paper we will report the results of the computation of cutoff rigidities of vertical and non-vertical incident cosmic ray particles. Non-vertical effective cutoff rigidities have been computed by tracing particle trajectories through the “real” geomagnetic magnetic field comprising the International Geomagnetic Reference Field model (IGRF95, IAGA Division 5 Working Group 8, 1996: Sabaka, T.J., Langel, R.A., Baldwin, R.T., Conrad, J.A. The geomagnetic field, 1900–1995, including the large scale fields from magnetospheric sources and NASA candidate models for the 1995 IGRF revision. J. Geomag. Geoelect. 49, 157–206, 1997.) and the Tsyganenko [Tsyganenko, N.A. A magnetospheric magnetic field model with a warped tail current sheet. Planet. Space Sci. 37, 5–20, 1989.] magnetosphere model. The computation have been done for the backward route (from Antarctica to Italy) of the Italian Antarctic ship survey 1996–1997, for geographic points corresponding to the daily average coordinates of the ship; for zenith angles 15°, 30°, 45° and 60°, and azimuth angles from 0° to 360° in steps of 45°. By means of the obtained non-vertical cutoffs the apparent cutoff rigidities have been calculated. The information on integral multiplicities of secondary neutrons detected by the neutron monitor in dependence of the zenith angle of incoming primary cosmic ray particles have also been used. This information is based on the theoretical calculations of meson-nuclear cascades of primary protons with different rigidities arriving to the Earth’s atmosphere at the zenith angles of 0°, 15°, 30°, 45°, 60° and 75°. The difference between the computed apparent and vertical cutoff rigidities reaches ∼1 GV at rigidities >7–8 GV. At rigidities of 10–16 GV, the difference between the apparent and vertical cutoff rigidities is larger than that obtained earlier by Clem et al. [Clem, J.M., Bieber, J.W., Duldig, M., Evenson, P., Hall, D., Humble, J.E. Contribution of obliquely incident particles to neutron monitor counting rate. J. Geophys. Res. 102, 26919–26926, 1997.] and Dorman et al. [Dorman, L.I., Villoresi, G., Iucci, N., Parisi, M., Tyasto, M.I., Danilova, O.A., Ptitsyna, N.G. Cosmic ray survey to Antarctica and coupling functions for neutron component near solar minimum (1996–1997), 3. Geomagnetic effects and coupling functions. J. Geophys. Res. 105, 21047–21056, 2000.]. 相似文献
830.
R.M. Gunasingha A.R. Fazely J.H. Adams Jr. H.S. Ahn G.L. Bashindzhagyan K.E. Batkov J. Chang M. Christl O. Ganel T.G. Guzik J. Isbert K.C. Kim E.N. Kouznetsov M.I. Panasyuk A.D. Panov W.K.H. Schmidt E.S. Seo N.V. Sokolskaya J.W. Watts J.P. Wefel J. Wu V.I. Zatsepin Z.W. Lin 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2008
We have performed a detailed Monte-Carlo (MC) simulation for the Advanced Thin Ionization Calorimeter (ATIC) detector using the MC code FLUKA-2005 which is capable of simulating particles up to 10 PeV. The ATIC detector has completed two successful balloon flights from McMurdo, Antarctica lasting a total of more than 35 days. ATIC is designed as a multiple, long duration balloon flight, investigation of the cosmic ray spectra from below 50 GeV to near 100 TeV total energy; using a fully active Bismuth Germanate (BGO) calorimeter. It is equipped with a large mosaic of silicon detector pixels capable of charge identification, and, for particle tracking, three projective layers of x–y scintillator hodoscopes, located above, in the middle and below a 0.75 nuclear interaction length graphite target. Our simulations are part of an analysis package of both nuclear (A) and energy dependences for different nuclei interacting in the ATIC detector. The MC simulates the response of different components of the detector such as the Si-matrix, the scintillator hodoscopes and the BGO calorimeter to various nuclei. We present comparisons of the FLUKA-2005 MC calculations with GEANT calculations and with the ATIC CERN data. 相似文献