Resumo

ARELLANO FERRO, A. Functional relationships for T_eff and log g in F-G supergiants from uvby - β photometry. Rev. mex. astron. astrofis [online]. 2010, vol.46, n.2, pp. 331-338. ISSN 0185-1101.

From photoelectric uvby - β data and recent accurate synthetic and spectroscopic values of T_eff and log g for 50 F-G supergiants, we have calculated functional relationships that lead to initial estimates of effective temperature and gravities for these types of stars. It is shown that while the T_eff relationships are calculated using the data on young massive supergiants, they are also valid for evolved stars of similar temperatures like post-AGB and RV Tau stars. The gravity can also be predicted from the Δ[c₁]index with an uncertainty of about 0.26 dex. Although a clear and significant trend between M_V and Δ[c₁] is seen, no calibration is found that predicts accurate values of M_V.

Palavras-chave : AGB and post-AGB; supergiants; techniques [photometric].