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| Paper: |
Revised Baade-Wesselink Analysis of RR Lyrae Stars |
| Volume: |
203, The Impact of Large-Scale Surveys on Pulsating Star Research, IAU Colloquium 176 |
| Page: |
176 |
| Authors: |
Cacciari, C.; Clementini, G.; Castelli, F.; Melandri, F. |
| Abstract: |
We have applied the Baade-Wesselink method to two field RR Lyrae stars, i.e. SW And and RR Cet, and derived their distances and physical parameters. With respect to previous B-W analyses we have applied the following improvements: i) use of all sets of available data, after proper comparison for homogeneity and compatibility; ii) use of the most recent and accurate model atmospheres, with turbulent velocity Vturb = 4 km s-1 and the no-overshooting approximation, and comparison with other treatments of convection; iii) use of the instantaneous gravity along the pulsation cycle rather than the mean value; iv) comparison with modified radial velocity curves according to various assumptions on radial velocity gradients in the atmosphere; and v) careful reanalysis of the temperature scale. The main aim of this study is to evaluate the effect of the above items on the B-W results and verify whether any (or a combination) of them can possibly account for the discrepancy of the absolute magnitude zero-point with respect to other independent determinations. |
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