On the possible relation between Am stars and Brown Dwarfs

SAFFE, C.; CALVO, D.; ALACORIA, J.; MIQUELARENA, P.; GONZÁLEZ, C.; FLORES, M.; GONZÁLEZ, E.; JAQUE ARANCIBIA, M.; COLLADO, A.; GUNELLA, F.

Buenos Aires

Congreso; 65º Reunión de la Asociación Argentina de Astronomía; 2023

Metallic-lined A stars (Am stars) are oftencomponents of short-period binary systems,where tidal interactions would result in lowrotational velocities and help to develop thechemical peculiarities observed. However,the origin of single Am stars and Am starsthat belong to wide binary systems isunclear. We studied a sample of 19 early-type stars, seven of them hosting hot BDsand 12 of them hosting hot Jupiter planets.We found that the incidence of Am starshosting hot BDs is higher than thefrequency of Am stars in general (differentto the case of Am stars hosting hot Jupiterplanets). This would imply that thepresence of hot BDs could play a role in thedevelopment of Am stars and possibly helpto mitigate the single Am problem(Saffe+2022).