Banca de QUALIFICAÇÃO: JOSAFARY PEREIRA DA SILVA CAMPELO

Uma banca de QUALIFICAÇÃO de DOUTORADO foi cadastrada pelo programa.
STUDENT : JOSAFARY PEREIRA DA SILVA CAMPELO
DATE: 28/03/2024
TIME: 14:30
LOCAL: Plataforma Google Meet
TITLE:

Photometric Variability Analysis in B-Type Stars Observed by the TESS Space Mission

KEY WORDS:

Stellar variability; TESS; Hot subdwarfs.

PAGES: 66
BIG AREA: Ciências Exatas e da Terra
AREA: Física
SUMMARY:

The study of photometric variability in massive stars is of fundamental importance for
understanding the internal structures of these bodies and their evolution along the HR diagram. In this
paper, we present an extensive manifold analysis of 377 B-type stars with light curves collected by the
TESS space mission. In this analysis we used three different methods, namely Fast Fourier Transform,
Lomb-Scargle and wavelet, accompanied by a rigorous visual inspection, with the aim of classifying the
types of variability present in each star. Our efforts revealed 161 stars with some kind of periodicity in
their time series and, among them, we highlight 22 targets that showed unambiguous rotation signatures,
with periods ranging from 5h to 5 days, 27 with pulsation modulation, with periods between 3h and 5
days, and 29 with characteristics of hot subdwarf stars, with periods in the range of 1h to 13h. For the
latter, our analysis also revealed strong indications that they are part of binary systems. The combination
of the techniques used for analysis, together with the construction of light curves provided by the TESS
mission, represent an important advance in the study and understanding of the phenomena governing hot
stars and, consequently, the upper regions of the HR diagram.

COMMITTEE MEMBERS:
Presidente - 1675216 - BRUNO LEONARDO CANTO MARTINS
Externo à Instituição - CARLOS EDUARDO FERREIRA LOPES
Interno - 3060853 - IZAN DE CASTRO LEÃO