Effective temperature and models for early a stars: Application to 78Vir (A2P)
The energy distribution (ED) of the cool Ap star 78Vir is presented from 1200 Å to 22000 Å at phase 0.0 of its 3.7220 dys rotation period. The ED is used to calculate the integrated flux and the Infrared Flux Method (IRFM,Blackwell and Shallis, 1977) is applied to derive the effective temperature and the angular diameter of 78Vir. A grid of models was then computed for the found effective temperature within its uncertainty, surface gravities around 4.0 and three different chemical compositions. A chisquare technique is used to sort out the best fit(s) to the observed ED.
KeywordsEnergy Distribution Effective Temperature Surface Gravity Model Flux Angular Diameter
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