Search for disks in exoplanets host stars

SAFFE, CARLOS; GÓMEZ, MERCEDES

La Plata, Argentina

Congreso; XLVI Reunión de la Asociación Argentina de Astronomía; 2003

AAA y Universidad Nacional de La Plata

Abstract. We have assembled a database wich comprises optical and infrared (IR) photometry of Exoplanet Host Stars (EH) and constructed the spectral energy distributions (SEDs) of these stars. We use several quantities to explore of excess IR emission with respect to the photospheric level. In particular, Mannings & Barlow´s (1998, ApJ 497:330) criteria identify IR excess in 19-26% of the class V EH sources (6-8 out of 31). Several searches for Vega-like systems estimate a similar fraction of objetcs with IR excess emission, among main sequence stars. This excess emission is likely due to the presence of dust in circumstellar disks. We compare que polarization properties of the EHs and the Vega-like candidate objects and found one order of magnitude difference between the median polarization values for these groups. We interpret this result as a dissipation effect of the disk material due to planet/s formation.