Spectroscopic studies of the solar corona I. Spatial variations in line parameters of green and red coronal lines

We obtained simultaneously profiles of the coronal green line (Fe XIV 5303 Angstrom) and red line ([Fe X] 6374 Angstrom) on a number of days at severa l regions covering an area of about 200 " x 500 " in the solar corona. The intensity, velocity, and width for both of these lines were computed by mak ing a Gaussian fit to the observed line profile. We find that in coronal st ructures the spatial variations in the red and green line intensities are c orrelated. The ratio of green- to red-line intensities varies between 0.6-9 .2 for different coronal structures. The value of the intensity ratio in an individual coronal structure also varies with height above the solar limb along the structure. The range of values of the intensity ratio observed im plies that most of the structures under investigation had a temperature in the range of 1.2-1.6 x 10(6) K. Also, we find that in coronal structures th e width of the red line increases with height above the limb, whereas the g reen-line width in the same region decreases with height. This behavior of the line widths can be explained if we assume the mixing of plasma in the m iddle and higher portions of the coronal structures by microturbulence or t raveling waves, which have been detected recently. No Her loops and activit y were seen in these regions during the observation periods.