Other
Scientific paper
Mar 1994
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1994apj...423..516a&link_type=abstract
The Astrophysical Journal, Part 1 (ISSN 0004-637X), vol. 423, no. 1, p. 516-521
Other
12
Chromosphere, Ionization Potentials, Neutral Particles, Solar Corona, Solar Transition Region, Abundance, Gas Pressure, Polarity, Sunspots
Scientific paper
Spectroscopic data from two flights of the Naval Research Laboratory's High Resolution Telescope and Spectrograph (HRTS) are analyzed for evidence of variations in relative abundances in the low chromosphere. Comparisons of sunspot, active region, and quiet-Sun data from HRTS II reveal decreases of intensities of sunspot lines from the first ionization stages of elements with low first ionization potential relative to both the active region and the quiet Sun. C I lines, however, are more intense in the sunspot than either the active region or the quiet Sun. Within a sunspot in Spacelab II data, the C I line at 156.1 nm is near its average intensity, whereas the Fe II line at 156.3 is much weaker than average. Both spots suggest a relative high value for the C I/Fe II abundance ratio. Within the zone of the same magnetic polarity as the sunspot (leading polarity) in the Spacelab II data, the brightest plages in C I show large C I/Fe II intensity ratios similar to those found in the sunspot. By contrast, the zones of following polarity on either side of the leading polarity show several well-defined areas of unusually low C I/Fe II intensity ratios associated with dark features in C I. The plages within these same zones have near normal or somewhat enhanced values for the C I/Fe II intensity ratios. It is noteworthy, also, that many of the brightest areas in C I do not coincide spatially with the brightest regions in Fe II. Neither do the darkest areas in C I align well with the darkest areas in Fe II. The association of high C I/Fe II intensity ratios with the zone of leading polarity and low-intensity ratios with zones of following polarity suggests that the iron abundance is dependent on the field polarity and is relatively low in the sunspot and the brighter plages in the zone of leading polarity and relatively high in C I dark flocculi in zones of following polarity. Failure of the brightest and darkest features in C I to align with the brightest and darkest features in Fe II further suggests that in the case of these particular features the Fe II abundance may vary inversely with the gas pressure, as well as with magnetic polarity. Other possible interpretations are discussed but are considered as being less viable.
No associations
LandOfFree
Separation of low first ionization potential ions from high first ionization potential neutrals in the low chromosphere does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with Separation of low first ionization potential ions from high first ionization potential neutrals in the low chromosphere, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Separation of low first ionization potential ions from high first ionization potential neutrals in the low chromosphere will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1870575