Projeto Observacional para 2020B - OP2020B-004

Autor: Alejandra Romero
Instituição: UFRGS

Co-autores:
Kepler de Souza Oliveira
Theylor Klippell

Título: Follow-up observations for DA white Dwarf variables from TESS

Resumo: In the last few years, space based observations have been available to study variable stars, including white dwarfs. In particular the TESS satellite is currently observing between 150 and 300 white dwarf stars every month. Observation runs last for a total of 27 days, in a long-cadence mode, taking an image every 120 s. Due to the small size of the TESS cameras, 15 cm, only relatively large variations can be detected, of the order of 10 mma for stars between 15th and 16th magnitude. In addition, due to the long exposure time, it can only detect periodicities longer than the Nyquist frequency of 240 s. As a result, we found periodicities in around 10 % of the observed sample of white dwarf stars. We propose to perform follow-up photometric observations of these variable white dwarfs to search for lower amplitude modes and higher frequency modes to allow a seismological study of these compact objects.