Projeto Observacional para 2016A - SO2016A-003

Autor: Stavros Akras
Instituição: UFRJ
e-mail: akras@astro.ufrj.br

Co-autores:
Denise R. Gonçalves
Lizette Ramirez
Clyne Niall
Boumis Panayiots

Título: Deciphering the true nature of candidate symbiotic stars

Resumo: Symbiotic stars (SySts) are interacting binary stars with a cold red giant, in most cases, and a hot white dwarf, accreting from the giant. The hot companion ionizes parts of the atmosphere or of the stellar wind expelled by the cool giant which resulting in the formation of colorful nebulae. These nebulae usually mimic planetary nebulae (PNe) hampering the proper classification on, as well as their separation from PNe. Several attempts have been made in order to provide a general tool for separating them (e.g. colour-colour diagrams), though the most direct methods are still preferable (detection of the O VI Raman scattered lineat 6830 A or the TiO absorpion features at wavelenght redder than 7000 A). We propose to obtain new, deep spectroscopic data of 7 PNe/SySts candidate in order to decipher their true nature, which is still controversial, and perform a detailed study of the nebula around them.