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| Paper: |
Revealing the Spectral Type Dependence of the Coronal FIP Effect |
| Volume: |
448, 16th Cambridge Workshop on Cool Stars, Stellar Systems, and the Sun |
| Page: |
1325 |
| Authors: |
Wood, B.; Linsky, J. L. |
| Abstract: |
The most widely studied coronal abundance anomaly is the
so-called “FIP effect'', where the abundances of elements with low
First Ionization Potential (FIP) are enhanced relative to the
photosphere. Many studies in the
past have reported a tendency for more active stars to have less of a
FIP effect, and for particularly active stars to even exhibit an
inverse FIP effect, where low FIP elements are depleted in the corona
instead of enhanced. However, we find that this activity dependence
is nonexistent among main sequence stars when the most active stars with
log LX > 29 are excluded. Extremely active stars normally
dominate coronal surveys since active stars are brighter and more
easily observed in X-rays, but by avoiding such extremes and focusing
solely on more normal stars we find a very different empirical view of
the FIP effect, one in which FIP bias is dependent on spectral type
instead of activity. This dependence indicates a strong connection
between coronal abundance and basic photospheric characteristics. |
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