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In Pursuit of the FIP Effect in Late-Type Stellar CoronaeSpectral line data for several coronally active stars, in addition to EUVE Deep Survey light curves, have been analysed under this program. Much difficulty has been encountered in the study that has resulted in fewer stars being analysed than had been hoped. The difficulties stemmed from the analysis of low X-ray spectra taken with the ASCA satellite that produced results that are strongly discrepant with respect to the EUVE results. There is no obvious explanation for this, though it appears that analysis of ASCA data systematically underestimate metal abundance in hot plasmas. Consequently, the final emphasis in our analyses has been on EUVE data. Observed line profiles have being fitted in order to measure their fluxes using IDL software specially developed under this and parallel efforts.The observed line profiles deviate from pure gaussian forms, but we have found the benefits of using additional functional forms in the fitting process to be of only very small value for the lines with highest S/N. The resulting line fluxes have being processed in terms of the coronal EM using new techniques. Resulting EM distribution models are being used to finalize metallicity and abundance estimates for the stars in the program. Special account of the influence of missing lines in the spectral models has been taken.
Document ID
19990114867
Acquisition Source
Goddard Space Flight Center
Document Type
Contractor or Grantee Report
Authors
Drake, Jeremy
(Smithsonian Astrophysical Observatory Cambridge, MA United States)
Date Acquired
August 19, 2013
Publication Date
May 1, 1999
Subject Category
Astrophysics
Funding Number(s)
CONTRACT_GRANT: NAG5-3173
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.
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