Published May 1980 | Version v1
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Solar wind flows associated with hot heavy ions

Description

Solar wind heavy ion spectra measured with the Vela instrumentation have been studied with the goal of determining the solar origins of various solar wind structures which contain anomalously high ionization states. Since the ionization states freeze-in close to the sun they are good indicators of the plasma conditions in the low and intermediate corona. Heavy ion spectra from three different periods throughout the solar cycle have been analyzed. These data are consistent with freezing-in temperatures ranging from approx. 1.5 x 106 K to higher than 9 x 106. The spectra indicating hot coronal conditions occur in roughly 1/7 of all measurements and almost exclusively in postshock flows (PSFs), nonshock related helium abundance enhancements (HAEs), or noncompressive density enhancements (NCDEs). The PSFs and HAEs are both probably interplanetary manifestations of solar flares. The observation of several flare-related HAEs which were not preceded by an interplanetary shock suggests that the flare-heated plasma can evolve into the solar wind without producing a noticeable shock at 1 AU. The NCDEs with hot heavy ions differ from the PSF-HAEs in several ways implying that they evolve from events or places with lower temperatures and less energy than those associated with the flares, but with higher temperatures and densities than the quiet corona. Active regions, coronal mass ejections, and equatorial streamers are possible sources for the NCDEs with spectra indicating hot coronal conditions. These events owe their enhanced densities to coronal processes as opposed to interplanetary dynamical processes. Models of the solar wind expansion demonstrate how some NCDEs can have extreme, nonequilibrium ionization distributions

Availability note (English)

MF available from INIS under the Report Number; Available from NTIS., PC A04/MF A01.

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Additional details

Publishing Information

Imprint Pagination
58 p.
Report number
LA--8344-T

INIS

Country of Publication
United States
Country of Input or Organization
United States
INIS RN
11550559
Subject category
S79: ASTROPHYSICS, COSMOLOGY AND ASTRONOMY;
Descriptors DEI
ENERGY SPECTRA; HEAVY IONS; HOT PLASMA; SATELLITES; SOLAR CORONA; SOLAR CYCLE; SOLAR WIND
Descriptors DEC
CHARGED PARTICLES; IONS; PLASMA; SOLAR ACTIVITY; SPECTRA