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Figure 1: Constraints on the position of the star  Ara in the HR diagram. The error box corresponds to the luminosity derived from the Hipparcos parallax and the effective temperature measured by Bensby et al. (2003). Other temperature determinations are: 1 - Santos et al. (2004a), 2 - Santos et al. (2004b), 3 - Laws et al. (2003) and4 - Favata et al. (1997). An example of an evolutionary track is drawn for the "overmetallic'' assumption (dashed line, see text). The asteroseismic constraints appear as three oblique lines: center line (solid) represents the models for which the large separations are exactly 90 Hz as observed in  Ara, while the two other lines stand for 89 Hz (top dot-dashed line) and 91 Hz (bottom dot-dashed line). The cross shows the point discussed in more detail, for comparison with the accretion case.

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In the text

	Figure 2: Same as Fig. 1 for the observational constraints on  Ara. Here the evolutionary track is drawn for the "accretion" assumption. The seismic constraints are represented for the accretion case as in Fig. 1.
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In the text

Figure 3: Echelle diagram for the overmetallic model. The lines represent the theoretical frequencies, the solid line is for l=0, the dotted line for l=1, the dashed line for l=2 and the long-dashed line for l=3. The symbols represent their observational counterpart. Open squares, full squares, open triangles and full triangles stand for l=0, l=1, l=2, l=3, respectively. Their size is proportionnal to the signal to noise ratio (see Paper I).

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In the text

	Figure 4: Same as Fig. 3 for the accretion model. Only the mode with the lowest frequency differs from Fig. 3 (see text).
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In the text

	Figure 5: Internal distribution for elements H, He, C, N, O, Ne and Mg for models OM (dashed lines) and AC (full lines). The lower right panel displays the global fraction, Z, of elements heavier than helium.
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In the text

	Figure 6: Small separations for model OM. The full and open circles are the observed values obtained for l=0-2 and l=1-3. The small dots represent values involving modes detected at a low signal to noise ratio (see Paper I). The theoretical computations are represented as a solid curve for l=0-2 and a dotted curve for l=1-3.
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In the text

	Figure 7: Same as Fig. 6 for model AC.
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In the text

Figure 8: Sound speed profiles inside AC (solid line) and OM (dashed line) models. The feature in the central region for the OM case compared to the AC case is due to the convective core. The sound velocity drops dramatically at its boundary and increases inside. The frequencies of the modes l=0 which progress down to the stellar center are affected by this behavior while those for which the turning point lies outside this region are not. This explains the behavior of the corresponding lines in the echelle diagram, also seen in the small separations.

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In the text