Astronomy and Astrophysics – Astrophysics – Solar and Stellar Astrophysics
Scientific paper
2010-05-24
Astronomy and Astrophysics
Astrophysics
Solar and Stellar Astrophysics
Latex file and 5 figures in color. Astronomy and Astrophysics (to be published)
Scientific paper
{The \ion{Na}{x} X-ray lines between 10.9 and 11.2~\AA\ have attracted little attention but are of interest since they enable an estimate of the coronal abundance of Na to be made. This is of great interest in the continuing debate on the nature of the FIP (first ionization potential) effect. } {Observations of the \ion{Na}{x} lines with the Solar Maximum Mission Flat Crystal Spectrometer and a rocket-borne X-ray spectrometer are used to measure the Na/Ne abundance ratio, i.e. the ratio of an element with very low FIP to one with high FIP.} {New atomic data are used to generate synthetic spectra which are compared with the observations, with temperature and the Na/Ne abundance ratio as free parameters.} {Temperature estimates from the observations indicate that the line emission is principally from non-flaring active regions, and that the Na/Ne abundance ratio is $0.07 \pm 50$\%.} {The Na/Ne abundance ratio is close to a coronal value for which the abundances of low-FIP elements (FIP $< 10$~eV) are enhanced by a factor of 3 to 4 over those found in the photosphere. For low-temperature ($T_e \leqslant 1.5$~MK) spectra, the presence of \ion{Fe}{xvii} lines requires that either a higher-temperature component is present or a revision of ionization or recombination rates is needed. }
Aggarwal Kanti M.
Keenan Francis P.
Landi Enrico
Phillips Kenneth J. H.
No associations
LandOfFree
Highly Ionized Sodium X-ray Line Emission from the Solar Corona and the Abundance of Sodium 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 Highly Ionized Sodium X-ray Line Emission from the Solar Corona and the Abundance of Sodium, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Highly Ionized Sodium X-ray Line Emission from the Solar Corona and the Abundance of Sodium will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-119497