Open AccessFe xii xii emission lines in solar active regions observed by the RES‐C spectroheliograph on the CORONAS‐I mission
Author(s) -
Zhitnik I. A.,
Kuzin S. V.,
Urnov A. M.,
Keenan F. P.,
Pinfield D. J.
Publication year - 1999
Publication title -
monthly notices of the royal astronomical society
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.058
H-Index - 383
eISSN - 1365-2966
pISSN - 0035-8711
DOI - 10.1046/j.1365-8711.1999.02756.x
Subject(s) - physics , spectrograph , astrophysics , spectral line , wavelength , line (geometry) , extreme ultraviolet lithography , emission spectrum , astronomy , optics , geometry , mathematics
Theoretical line intensity ratios involving Fe xii transitions in the 186–201 Å wavelength range are compared with observational data for five solar active regions, obtained by the RES‐C spectroheliograph on the CORONAS‐I mission. Generally good agreement is found between theory and observation, hence resolving discrepancies previously found in the comparison of calculations with active region and subflare spectra from the Solar EUV Rocket Telescope and Spectrograph ( SERTS ). However, the Fe xii 190.06‐ and 201.12‐Å lines are blended with Fe x 190.04 Å and Fe xiii 201.13 Å, respectively. In addition, a weak feature at ∼197 Å, tentatively identified as Fe xii 196.87 Å, does not appear to be due to this ion.