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21.
S. J. Bame J. R. Asbridge J. T. Gosling M. Halbig G. Paschmann N. Sckopke H. Rosenbauer 《Space Science Reviews》1979,23(1):75-92
High temporal resolution measurements of solar wind electrons at the Earth's bow shock on the dawn side have been made with the LASL/MPI fast plasma experiments on ISEE-1 and 2. One dimensional, 1-d, temperatures, T
e
, and densities, N
e
, are obtained every 0.3 s and 2-d values are obtained every 3 s. Profiles of T
e
and N
e
at the shock usually are found to be similar to one another and also to the profile of the magnetic field magnitude. The time scale of electron thermalization varies from about 0.5 s to greater than 1 min, depending importantly on the shock motion and the orientation of the magnetic field. Typical thermalization times from 05:00–12:00 LT are 10 s, considerably shorter than proton thermalization times at the shock. This time scale corresponds to a distance of 100 km, comparable to but somewhat larger than the typical ion inertial length. The electron thermalization times are significantly longer than some of the values frequently cited in the past. At the end of the electron thermalization there typically is an overshoot in electron thermal pressure followed by an undershoot which give the pressure profile of the shock the appearance of a damped wave. Ion thermalization is essentially completed by the time the electron pressure wave is damped. The most probable value of the electron temperature ratio across the shock is 1.7, and this value is relatively independent of the Sun-Earth-satellite angle,
ss
, for
ss
between 25° and 100°.The Los Alamos Scientific Laboratory requests that the publisher identify this article as work performed under the auspices of the Department of Energy.By acceptance of this article, the publisher recognizes that the U.S. Government retains a non-exclusive, royalty-free license to publish or reproduce the published form of this contribution, or to allow others to do so, for U.S. Government purposes. 相似文献
22.
Ulysses observed well-defined stream interaction regions, SIRs, associated with solar wind stream structure up to a latitude of S65°
and shocks to at least a latitude of S71° during the second polar orbit. These SIRs and shocks produced a substantial heliospheric
processing of the solar wind. Only a subset of the SIRs recurred on successive solar rotations and only about half of the
well-defined SIRs observed poleward of S9.8° were bounded by forward-reverse shock pairs. The majority of the SIRs had local
magnetic topologies and azimuthal orientations similar to, but meridional tilts different from, those observed in the first
polar orbit when most SIRs corotated with the Sun. The irregular meridional tilts presumably were a consequence of a complex
coronal geometry and the temporally evolving nature of the solar wind flow at this time. A lack of reverse shocks poleward
of S54° (with one exception) and a lack of well defined SIRs poleward of S65° is evidence that SIRs develop more slowly with
distance at high latitudes.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献