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741.
N.U. Crooker J.T. Gosling V. Bothmer R.J. Forsyth P.R. Gazis A. Hewish T.S. Horbury D.S. Intriligator J.R. Jokipii J. Kóta A.J. Lazarus M.A. Lee E. Lucek E. Marsch A. Posner I.G. Richardson E.C. Roelof J.M. Schmidt G.L. Siscoe B.T. Tsurutani R.F. Wimmer-Schweingruber 《Space Science Reviews》1999,89(1-2):179-220
Corotating interaction regions (CIRs) in the middle heliosphere have distinct morphological features and associated patterns
of turbulence and energetic particles. This report summarizes current understanding of those features and patterns, discusses
how they can vary from case to case and with distance from the Sun and possible causes of those variations, presents an analytical
model of the morphological features found in earlier qualitative models and numerical simulations, and identifies aspects
of the features and patterns that have yet to be resolved.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
742.
Energetic particles associated with Corotating Interaction Regions (CIRs) are observed throughout the inner and middle heliosphere,
showing large positive (>100%/AU) radial intensity gradients. Their appearance at 1 AU is associated with the appearance of
fast, recurrent solar wind streams. At several AU, CIR energetic particles are accelerated at shocks which propagate away
from the interface of fast and slow solar wind streams. CIR energy spectra at 1 AU cover the range >35 keV to several MeV/amu;
the spectra steepen above ∼1 MeV/amu, and show no turnover even at the lowest energies. The ion composition of CIRs is similar
to solar material, but with significant differences that might be due to properties of the seed population and/or the acceleration
process. This paper summarizes properties of energetic particles in CIRs as known through the early 1990s, prior to the launch
of the Ulysses, and WIND spacecraft, whose new results are presented in Kunow, Lee et al. (1999) in this volume.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
743.
T. M. Donahue 《Space Science Reviews》1977,20(3):259-263
This paper develops the rationale for a program of Venus exploration by man. 相似文献
744.
Malandraki O.E. Sarris E.T. Lanzerotti L.J. Maclennan C.G. Pick M. Tsiropoula G. 《Space Science Reviews》2001,97(1-4):263-268
In January 2000, the Ulysses spacecraft observed an ICME event at 43° S heliographic latitude and ∼ 4.1 AU. We use electron (E
e>38 keV) observations to trace the topology of the IMF embedded within the ICME. The still controversial issue of whether
ICMEs have been detached from the solar corona or are still magnetically anchored to it when they arrive at the spacecraft
is tackled. An in ecliptic ICME event is also presented.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
745.
Lario D. Haggerty D.K. Roelof E.C. Tappin S.J. Forsyth R.J. Gosling J.T. 《Space Science Reviews》2001,97(1-4):277-280
On day 49 of 1999 a strong interplanetary shock was observed by the ACE spacecraft located at 1 AU from the Sun. This shock
was followed 10 hours later by a magnetic cloud (MC). A large solar energetic particle (SEP) event was observed in association
with the arrival of the shock and the MC at ACE. The Ulysses spacecraft, located at 22° S heliolatitude and nearly the same
ecliptic longitude as ACE, observed a large SEP event beginning on day 54 that peaked with the arrival of a solar wind and
magnetic field disturbance on day 61. A magnetic cloud was observed by Ulysses on days 63–64. We suggest a scenario in which both spacecraft intercepted the same MC, although sampling different regions
of it. We describe the effects that the MC produced on the streaming of energetic particles at both spacecraft.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
746.
O. Moullard R.G. Marsden T.R. Sanderson C. Tranquille R.J. Forsyth B.E. Goldstein 《Space Science Reviews》2001,97(1-4):289-292
We present and compare observations of energetic protons during the two first transits of the Ulysses spacecraft from low to high latitudes in the southern heliosphere. Protons in the energy range 1.8–3.8 MeV from the COSPIN
experiment are studied for global trends and in relation to some ambient structures in the solar wind (corotating interaction
region, forward/reverse shock). The global trends show the large dependence on the heliospheric condition and solar activity,
including indications of a larger ambient particle population during the rising phase of solar activity and more efficient
solar wind particle accelerators during the declining phase. More enhancements in the proton flux intensity are time associated
with forward shocks than reverse contrary to first pass. Recurrent structures are found even during the second transit. Some
latitude dependent periodicities are observed that could relate to the differential solar rotation.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
747.
G. Wibberenz H.V. Cane I.G. Richardson T.T. von Rosenvinge 《Space Science Reviews》2001,97(1-4):343-347
The maximum inclination of the heliospheric current sheet (the tilt angle) and the magnitude B of the heliospheric magnetic field are often used to characterize cosmic ray (CR) modulation. The relevance of B is likely to be the coupling of the interplanetary diffusion coefficients K to the field magnitude in a relation K∝B
−n. In this paper we study the coupled influence of tilt angle and magnetic field variations on the modulation of cosmic rays
at neutron monitor energies for the 1974 mini-cycle and for the onsets of solar cycles 21, 22, and 23. It is suggested that
for A>0 polarity epochs, the sensitivity of the CR response to variations in B is partly controlled by the size of the tilt angle, α. The onsets of cycles 21 and 23 exhibit differences, related to phase
differences in these parameters. A simple model is used to predict the CR response to variations in B.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
748.
L.Q. Zhang C. Wang J.Y. Wang A.T.Y. Lui 《Advances in Space Research (includes Cospar's Information Bulletin, Space Research Today)》2019,63(10):3077-3087
Utilizing ACE satellite observations from 1998 to 2009, we performed the elaborate study on the properties of the clock angle θCA (arctan(By/Bz) (?90° to 90°) of the interplanetary magnetic field (IMF) in the solar wind at 1?AU. The solar wind with northward IMF (NW-IMF) and southward IMF (SW-IMF) are analyzed, independently. Statistical analysis shows that the solar wind with SW-IMF and NW-IMF has similar properties in general, including their durations, the IMF Bz and By components, and the IMF θCA. Then, the solar wind with NW-IMF (SW-IMF) is classified into five different temporal scales according to the duration of the NW-IMF (SW-IMF), i.e., very-short wind of 10–30?min, short-scale wind of 0.5–1?h, moderate-scale wind of 1–3?h, long-scale wind of 3–5?h, and super-long wind >5?h. Our analysis reveals that the IMF θCA has a distinct decrease with increase of the temporal scale of the solar wind. Next, the solar wind is classified into two groups, i.e., the high-speed solar wind (>450?km/s) and the low-speed solar wind (<450?km/s). Our analysis indicates that the IMF θCA depends highly on the solar wind speed. Statistically, high-speed solar wind tends to have larger IMF θCA than low-speed solar wind. The evolutions of the solar wind and IMF with the solar activity are further studied, revealing no clear solar variation of the IMF θCA. Finally, we analyze the monthly variation of the IMF θCA. Superposed epoch result strongly suggests the seasonal variation of the IMF θCA. 相似文献
749.
The Dawn Mission to Vesta and Ceres 总被引:1,自引:0,他引:1
A review of present understanding of the dissipation region in magnetic reconnection is presented. The review focuses on results of the thermal inertia-based dissipation mechanism but alternative mechanisms are mentioned as well. For the former process, a combination of analytical theory and numerical modeling is presented. Furthermore, a new relation between the electric field expressions for anti-parallel and guide field reconnection is developed. 相似文献
750.
ARTEMIS Science Objectives 总被引:1,自引:0,他引:1
D. G. Sibeck V. Angelopoulos D. A. Brain G. T. Delory J. P. Eastwood W. M. Farrell R. E. Grimm J. S. Halekas H. Hasegawa P. Hellinger K. K. Khurana R. J. Lillis M. ?ieroset T.-D. Phan J. Raeder C. T. Russell D. Schriver J. A. Slavin P. M. Travnicek J. M. Weygand 《Space Science Reviews》2011,165(1-4):59-91
NASA??s two spacecraft ARTEMIS mission will address both heliospheric and planetary research questions, first while in orbit about the Earth with the Moon and subsequently while in orbit about the Moon. Heliospheric topics include the structure of the Earth??s magnetotail; reconnection, particle acceleration, and turbulence in the Earth??s magnetosphere, at the bow shock, and in the solar wind; and the formation and structure of the lunar wake. Planetary topics include the lunar exosphere and its relationship to the composition of the lunar surface, the effects of electric fields on dust in the exosphere, internal structure of the Moon, and the lunar crustal magnetic field. This paper describes the expected contributions of ARTEMIS to these baseline scientific objectives. 相似文献