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741.
742.
We calculate the conditions of pickup protons inside the termination shock. Outside 50 AU the partial pressure of pickup protons is greater than the magnetic pressure by a factor of > 10, and greater than the partial pressure of solar wind protons by a factor of > 100. Thus, pickup protons have a significant dynamical influence on the structures of the solar wind in the outer heliosphere. 相似文献
743.
744.
The Heavy Ion Counter on the Galileo spacecraft will monitor energetic heavy nuclei of the elements from C to Ni, with energies from 6 to 200 MeV nucl-1. The instrument will provide measurements of trapped heavy ions in the Jovian magnetosphere, including those high-energy heavy ions with the potential for affecting the operation of the spacecraft electronic circuitry. We describe the instrument, which is a modified version of the Voyager CRS instrument. 相似文献
745.
746.
THE DIGITAL WAVE-PROCESSING EXPERIMENT ON CLUSTER 总被引:1,自引:0,他引:1
L. J. C. Woolliscroft H. St. C. Alleyne C. M. Dunford A. Sumner J. A. Thompson S. N. Walker K. H. Yearby A. Buckley S. Chapman M. P. Gough 《Space Science Reviews》1997,79(1-2):209-231
The wide variety of geophysical plasmas that will be investigated by the Cluster mission contain waves with a frequency range from DC to over 100 kHz with both magnetic and electric components. The characteristic duration of these waves extends from a few milliseconds to minutes and a dynamic range of over 90 dB is desired. All of these factors make it essential that the on-board control system for the Wave-Experiment Consortium (WEC) instruments be flexible so as to make effective use of the limited spacecraft resources of power and telemetry-information bandwidth. The Digital Wave Processing Experiment, (DWP), will be flown on Cluster satellites as a component of the WEC. DWP will coordinate WEC measurements as well as perform particle correlations in order to permit the direct study of wave/particle interactions. The DWP instrument employs a novel architecture based on the use of transputers with parallel processing and re-allocatable tasks to provide a high-reliability system. Members of the DWP team are also providing sophisticated electrical ground support equipment, for use during development and testing by the WEC. This is described further in Pedersen et al. (this issue). 相似文献
747.
The ACE Magnetic Fields Experiment 总被引:2,自引:0,他引:2
Smith C.W. L'Heureux J. Ness N.F. Acuña M.H. Burlaga L.F. Scheifele J. 《Space Science Reviews》1998,86(1-4):613-632
The magnetic field experiment on ACE provides continuous measurements of the local magnetic field in the interplanetary medium.
These measurements are essential in the interpretation of simultaneous ACE observations of energetic and thermal particles
distributions. The experiment consists of a pair of twin, boom- mounted, triaxial fluxgate sensors which are located 165 inches
(=4.19 m) from the center of the spacecraft on opposing solar panels. The electronics and digital processing unit (DPU) is
mounted on the top deck of the spacecraft. The two triaxial sensors provide a balanced, fully redundant vector instrument
and permit some enhanced assessment of the spacecraft's magnetic field. The instrument provides data for Browse and high-level
products with between 3 and 6 vector s−1 resolution for continuous coverage of the interplanetary magnetic field. Two high-resolution
snapshot buffers each hold 297 s of 24 vector s−1 data while on- board Fast Fourier Transforms extend the continuous data
to 12 Hz resolution. Real-time observations with 1-s resolution are provided continuously to the Space Environmental Center
(SEC) of the National Oceanographic and Atmospheric Association (NOAA) for near- instantaneous, world-wide dissemination in
service to space weather studies. As has been our team's tradition, high instrument reliability is obtained by the use of
fully redundant systems and extremely conservative designs. We plan studies of the interplanetary medium in support of the
fundamental goals of the ACE mission and cooperative studies with other ACE investigators using the combined ACE dataset as
well as other ISTP spacecraft involved in the general program of Sun-Earth Connections.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
748.
On the Slow Solar Wind 总被引:1,自引:0,他引:1
A theory for the origin of the slow solar wind is described. Recent papers have demonstrated that magnetic flux moves across
coronal holes as a result of the interplay between the differential rotation of the photosphere and the non-radial expansion
of the solar wind in more rigidly rotating coronal holes. This flux will be deposited at low latitudes and should reconnect
with closed magnetic loops, thereby releasing material from the loops to form the slow solar wind. It is pointed out that
this mechanism provides a natural explanation for the charge states of elements observed in the slow solar wind, and for the
presence of the First-Ionization Potential, or FIP, effect in the slow wind and its absence in fast wind. Comments are also
provided on the role that the ACE mission should have in understanding the slow solar wind.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
749.
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
750.
P. C. Frisch M. Bzowski E. Grün V. Izmodenov H. Krüger J. L. Linsky D. J. McComas E. Möbius S. Redfield N. Schwadron R. Shelton J. D. Slavin B. E. Wood 《Space Science Reviews》2009,146(1-4):235-273
Interstellar material (ISMa) is observed both inside and outside of the heliosphere. Relating these diverse sets of ISMa data provides a richer understanding of both the interstellar medium and the heliosphere. The galactic environment of the Sun is dominated by warm, low-density, partially ionized interstellar material consisting of atoms and dust grains. The properties of the heliosphere are dependent on the pressure, composition, radiation field, ionization, and magnetic field of ambient ISMa. The very low-density interior of the Local Bubble, combined with an expanding superbubble shell associated with star formation in the Scorpius-Centaurus Association, dominate the properties of the local interstellar medium (LISM). Once the heliosphere boundaries and interaction mechanisms are understood, interstellar gas, dust, pickup ions, and anomalous cosmic rays inside of the heliosphere can be directly compared to ISMa outside of the heliosphere. Our understanding of ISMa at the Sun is further enriched when the circumheliospheric interstellar material is compared to observations of other nearby ISMa and the overall context of our galactic environment. The IBEX mission will map the interaction region between the heliosphere and ISMa, and improve the accuracy of comparisons between ISMa inside and outside the heliosphere. 相似文献