[Loops] A&A paper on abundances and temperatures of AR cores

[Dr G. Del-Zanna]

Dear all,

Abundance measurements in Active Region Cores

Interestingly, a re-analysis of the good old SMM/FCS observations of 
quiescent active region cores, using up-to-date atomic data, confirms 
earlier results based on Hinode/EIS (Del Zanna 2013, A&A, 555, A47).

The Fe/Ne and Fe/O ratios are remarkably similar for different ARs, with
an FIP bias of about 3, the same as was found in terms of Fe/Ar and Fe/S
for a few ARs from Hinode EIS (Del Zanna 2013,A&A, 558, A73). 
These abundances are different from previous results by other authors, 
but apply only to the hot (about 3 MK) AR core loops.

In terms of emission above 3 MK, the SMM/FCS results are also in agreement
with previous results from Hinode EIS, with a sudden drop in the emission
measure for higher temperatures, and very little Fe XVIII emission.

The MAGIXS instrument would provide an excellent opportunity to combine
simultaneous EUV and X-ray spectroscopy of ARs, and to study further
these diagnostics.

The  A&A paper is available at
http://adsabs.harvard.edu/abs/2014A%26A...565A..14D
and a preprint at
http://solar.physics.montana.edu/cgi-bin/eprint/index.pl?entry=23180

Giulio and Helen