All Figures

	Figure 1: The area on the Sun under study here seen in light from the million Kelvin corona (Fe 9/ 10 lines) and from the cool chromosphere (He 2). The vertical line shows the position of the slit of the SUMER spectrograph used to acquire the emission line profiles. The slit was positioned well outside regions of coronal activity, i.e. in the ambient background corona. (Images from SOHO/EIT.)
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In the text

Figure 2: Spectrum in the line of O 5 at 62.9 nm (left panel) at the approximate slit location shown in Fig. 1. Note that the emission of this line formed at about 240 000 K extends well above the white light limb of the Sun. The right panels show individual spectra as bars (Poisson statistics; spatially binned) at the location along the slit indicated at the left panel. The solid lines are single Gaussian fits to the line profiles.

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In the text

Figure 3: Variation of line intensity (dotted-dashed, left axis) and line width (solid, right axis) as a function of distance above the limb for the lines of O 5 at 62.9 nm (see also Fig. 2) and S 6 at 93.3 nm. The shaded areas indicate the error estimates for the line width. The dashed curves show the variation of line width for Mg 10 as published by Hassler et al. (1990) (scaled to match O 5 and S 6 on disk values respectively). The vertical dashed lines show the position of the limb, the dotted lines indicate the location where the stray-light becomes important (outside about 15 ). The axis to the far right shows a scale of the line width converted into an ion temperature.

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In the text

Figure 4: Schematic representation of the ion-cyclotron heating at the base of a coronal funnel. The left panel ( a)) indicates the magnetic field geometry of the coronal funnel. Where the funnel expands the magnetic field drops rapidly ( a), b); dark shaded area). Thus in that region a large range of gyrofrequencies is covered ( b)). As the incident Alfvén wave spectrum is (roughly) a power law ( c)), the power absorbed in the small region of rapid field expansion is very large (dark shaded area). That is why the heating rate is highest in the region of strong magnetic field gradients ( d)).

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In the text

	Figure 5: Ion temperatures perpendicular to the magnetic field computed using the model of ion-cyclotron absorption of high-frequency Alfvén waves in a coronal funnel. The electron temperature is basically the same as for the protons.
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In the text