Fe XII emission lines in solar active regions observed by the RES-C spectroheliograph on the CORONAS-I mission

Theoretical line intensity ratios involving Fe XII transitions in the 186-2 01 Angstrom wavelength range are compared with observational data for five solar active regions, obtained by the RES-C spectroheliograph on the CORONA S-I mission. Generally good agreement is found between theory and observati on, hence resolving discrepancies previously found in the comparison of cal culations with active region and subflare spectra from the Solar EW Rocket Telescope and Spectrograph (SERTS). However, the Fe XII 190.06- and 201.12- Angstrom lines are blended with Fe x 190.04 Angstrom and Fe XIII 201.13 Ang strom, respectively. In addition, a weak feature at similar to 197 Angstrom , tentatively identified as Fe XII 196.87 Angstrom, does not appear to be d ue to this ion.