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151.
152.
A. Devdariani 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2014
The review is aimed at the discussion of recent results on spectral profiles produced in collisions of few-electron atoms/ions. Calculations of spectral profiles produced by atom/ion collisions need some preliminary quantum-chemical information such as potential energy surfaces, dipole transition moments, etc. The main advantage of few-electron systems is that all input data can be obtained ab initio or analytically, thus the profiles calculated do not include any fit parameters. Two specific examples have been discussed. The first one deals with radiative transitions accompanying charge-exchange in collisions of one-electron ions with bare nuclei. The second example concerns radiative transitions produced by H− + H collisions. 相似文献
153.
154.
155.
航空电瓶内阻测量与剩余容量探讨 总被引:2,自引:0,他引:2
论述了电瓶内阻的基本测量方法。利用3550电瓶内阻测试仪对典型的航空电瓶进行实际测量,结果表明,对于酸性电瓶判断比较正确,而对碱性电瓶判断不正确。 相似文献
156.
The combination of recent observational and theoretical work has completed the catalog of the sources of heliospheric Pickup
Ions (PUIs). These PUIs are the seed population for Anomalous Cosmic Rays (ACRs), which are accelerated to high energies at
or beyond the Termination Shock (TS). For elements with high First Ionization Potentials (high-FIP atoms: e.g., H, He, Ne,
etc.), the dominant source of PUIs and ACRs is from neutral atoms that drift into the heliosphere from the Local Interstellar
Medium (LISM) and, prior to ionization, are influenced primarily by solar gravitation and radiation pressure (for H). After
ionization, these interstellar ions are pickup up by the solar wind, swept out, and are either accelerated near the TS or
beyond it. Elements with low first ionization potentials (low-FIP atoms: e.g., C, Si, Mg, Fe, etc.) are also observed as PUIs
by Ulysses and as ACRs by Wind and Voyager. But the low-FIP composition of this additional component reveals a very different
origin. Low-FIP interstellar atoms are predominantly ionized in the LISM and therefore excluded from the heliosphere by the
solar wind. Remarkably, a low-FIP component of PUIs was hypothesized by Banks (J. Geophys. Res. 76, 4341, 1971) over twenty years prior to its direct detection by Ulysses/SWICS (Geiss et al., J. Geophys. Res. 100(23), 373, 1995) The leading concept for the generation of Inner Source PUIs involves an effective recycling of solar wind on grains near
the Sun, as originally suggested by Banks. Voyager and Wind also observe low-FIP ACRs, and a grain-related source appears
likely and necessary. Two concepts have been proposed to explain these low-FIP ACRs: the first concept involves the acceleration
of the Inner Source of PUIs, and the second involves a so-called Outer Source of PUIs generated from solar wind interaction
with the large population of grains in the Kuiper Belt. We review here the observational and theoretical work over the last
decade that shows how solar wind and heliospheric grains interact to produce pickup ions, and, in turn, anomalous cosmic rays.
The inner and outer sources of pickup ions and anomalous cosmic rays exemplify dusty plasma interactions that are fundamental
throughout the cosmos for the production of energetic particles and the formation of stellar systems. 相似文献
157.
158.
S. Pedoux A. Boudard J. Cugnon J.-C. David S. Leray D. Mancusi 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2011
Radiation hazard for space missions is mainly due to cosmic ray protons, helium nuclei and light ions, whose energy spectrum is maximum around 1 GeV per nucleon but remains non-negligible for energies up to 15 GeV per nucleon. Nuclear reactions induced by high energy protons are often described by intranuclear cascade plus evaporation models. The attention is focused here on the Liège Intranuclear Cascade model (INCL), which has been shown to reproduce fairly well a great deal of experimental data for nucleon-induced reactions in the 200 MeV to 2 GeV range, when coupled with the ABLA evaporation-fission code. In order to extend the model to other conditions relevant for space radiation, three improvements of INCL are under development. They are reported on here. First, the reaction model has been extended to nucleon–nucleus reactions at incident energies up to 15 GeV, mainly by the inclusion of additional pion production channels in nucleon–nucleon collisions during the cascade. Second, a coalescence mechanism for the emission of light charged particles has been implemented recently. Finally, the model has been modified in order to accommodate light ions as projectiles. First results are shown and compared with illustrative experimental data. Implications for issues concerning radiation protection in space are discussed. 相似文献
159.
160.
R. A. Leske R. A. Mewaldt A. C. Cummings J. R. Cummings E. C. Stone T. T. Von Rosenvinge 《Space Science Reviews》1996,78(1-2):149-154
Measurements of the anomalous cosmic ray (ACR) isotopic composition have been made in three regions of the magnetosphere accessible from the polar Earth orbit of SAMPEX, including the interplanetary medium at high latitudes and geomagnetically trapped ACRs. At those latitudes where ACRs can penetrate the Earth's magnetic field while fully stripped galactic cosmic rays (GCRs) of similar energies are excluded, a pure ACR sample is observed to have the following composition: 15N/N < 0.023, 18O/16O < 0.0034, and 22Ne/20Ne = 0.077(+0.085, –0.023). We compare our values with those found by previous investigators and with those measured in other samples of solar and galactic material. In particular, a comparison of 22Ne/20Ne measurements from various sources implies that GCRs are not simply an accelerated sample of the local interstellar medium. 相似文献