All Figures

Figure 1: The input stellar surface temperature distribution. The Mercator projection at the top shows stellar longitude along its abscissa and stellar latitude along its ordinate. Below the Mercator projection are four spherical projections of the stellar surface at four different rotational phases, given above each projection along with the average effective temperature of all the visible surface pixels. Note that the rotational phase and the stellar longitude run in opposite directions. To the right is a bar linking greyscale and effective temperature. The surface effective temperature is 4750 K in the photosphere, 3750 K in the spot, and 5250 K in the ring.

Open with DEXTER


In the text

	Figure 2: Spectral regions surrounding the Fe I 6141.7 Å and Si I 6155.1 Å lines calculated for three different temperatures. The spectral regions shown correspond roughly to the regions actually used in the inversions. The main spectral lines in each region are identified in the text.
Open with DEXTER


In the text

Figure 3: Reconstructing the stellar surface consisting of a dark spot surrounded by a bright ring. Top left: the reconstructed stellar surface. The projections, annotations and temperature scale are as in Fig. 1, with some additional annotations on top of the Mercator projection. These give the projected equatorial rotational velocity , the inclination i, and the minimum and maximum effective temperatures in the surface pixels. Top right: the "observed'' (squares) and reconstructed (solid line) photometry ( from top to bottom: the V band light curve, the B-V colour curve, and the U-B colour curve). Bottom: the "observed'' (tick marks) and reconstructed (solid lines) spectral line profiles in the phase interval 0.250-0.725.

Open with DEXTER


In the text

	Figure 4: The same as Fig. 3, but for more realistic observations.
Open with DEXTER


In the text