All Figures

	Figure 1: A plot of the gf values from the Bhatia & Doschek (1995) DW calculation vs. the values scaled using the SS results (gf'). Only the values for the dipole-allowed transitions to the 3s 3p53d levels included in the model ion are shown. The corrections are quite large, particularly for small gf values.
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In the text

	Figure 2: The fractional level populations of the ground and the metastable levels using the present model, with all excitations included ( top), and with only excitations from the first 3 levels included ( bottom). Note the large differences in the metastable level populations, which in turn also affect the entire level balance of the ion (see also Table 6).
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In the text

Figure 3: The Fji curves relative to a coronal condensation observed from the ground at 1.02  during the 1965 solar eclipse (Jefferies et al. 1971). The curves are labelled with increasing numbers. For each line, we indicate: the observed intensities  ; the lower and upper level index corresponding to Table 3; the theoretical wavelength. The agreement between the curves is satisfactory, considering the various uncertainties. The error bar (30%) gives an indication of the agreement between observed and calculated intensities. With the exception of the 1-2 transition, the Fji curves are largely independent of the chosen temperature (log T[K] = 6.0).

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In the text

Figure 4: The Fji curves relative to the Skylab ATM observations 40 above an active region reported by Sandlin et al. (1977). Note that some lines are blends of two transitions. Also note that the ordinate of the plot spans more than three orders of magnitude. The agreement between the curves is satisfactory (the error bar indicates a 30%), with the exception of the 1582 Å line, which obviously cannot be ascribed to the 10-24 Fe X transition, the theorethical intensity of which is predicted to be more than two orders of magnitude weaker than the observed line. The Fji curves have been calculated at T=1 MK. However, it should be noted that temperature effects are not present for these lines.

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In the text

	Figure 5: The Fji curves relative to the Skylab ATM observations reported by Feldman & Doschek (1977). Note that the ordinate of the plot spans three orders of magnitude. These results confirm those presented in Fig. 4 (the error bar indicates a 25%). The Fji curves have been calculated at log T[K] = 6. However, it should be noted that temperature effects are not present for these lines.
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In the text

Figure 6: Top: average off-limb SUMER spectrum showing the bright 1028.02 and 1463.5 Å Fe X forbidden lines. Bottom: the relative Fji curves (calculated at log T[K] = 6.0). The agreement between the 1028.02 Å (here identified as a blend of the 5-24 and 4-24 transitions) and the 1463.5 Å line is satisfactory (the error bar indicates a 15%). The line observed at 1042.5 Å, tentatively identified by Feldman et al. (1997) with the Fe X 6-24 transition is obviously due to an unidentified line.

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In the text

Figure 7: The Fji curves relative to the full-Sun spectrum of Malinovsky & Heroux (1973). As indicated in the figure, the intensities of the 257.26 and 182.3 Å lines have been rescaled (by factors of 0.4 and 0.08) taking into account known blends. The agreement between our present model and the Malinovsky & Heroux (1973) data is excellent (the error bar indicates a 15%), with the exclusion of the 190.04 Å line that is obviously blended. The curves also indicate an electron density log  = 8.8 cm-3, in excellent agreement with the values derived from other ions. Note that transitions labelled 1,4 have almost coincident curves. The Fji curves have been calculated at log T[K] = 6, appropriate for a whole-Sun dataset. However, temperature effects are not present for these lines.

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In the text

Figure 8: The Fji curves relative to the theta-pinch laboratory spectra of Datla et al. (1975), first ( top) and second ( bottom) case. The estimated electron density and temperature at the time of peak intensity of the discharge were  =   cm-3 and  = 1.6, 1.1 MK for the first and second case, respectively. The Fji curves have been calculated at these temperatures. Corrections due to optical depth effects were applied by Datla et al. (1975) to the intensities of the 1-30 (first case) and 1-30, 1-28 transitions (second case). Note the good agreement between theory and observations (the error bar indicates a 15%), with the exception of the 190.04 Å line, which is clearly blended, as also shown in Fig. 7.

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In the text

Figure 9: Top: a solar CDS off-limb spectrum (Del Zanna 1999) with the newly identified 18-43 line at 337.27 Å. The 21-43 line in these off-limb spectra is blended with an Fe XI line. Bottom: Fji curves relative to the SERTS-89 calibrated data of an on-disk active region average spectrum (Thomas & Neupert 1994). The lines 1, 2, 4 (observed at 257.257, 345.735, 337.238 Å) are in excellent agreement (the error bar indicates a 15%), indicating a density log  = 9.5 [cm-3], in good agreement with results from other ions (see Young et al. 1998). This confirms the identifications of both 257.257 and 337.27 Å lines. The 365.543 Å line is a well-known blend with a Ne V line and in fact is not in agreement with the others. The Fji curves have been calculated at T=1 MK, the temperature of maximum ion fraction in ionization equilibrium. Temperature effects only slightly change the positioning of the 345.735, 365.543 Å curves relative to all the others, and do not affect the conclusions. In on-disk observations, the 21-43 line is blended with Fe XI and Mg VI lines. In the plot, it has been assumed that the 21-43 Fe X transition contributes by 12% to the observed line.

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In the text