Variabilidade estelar e o método de trânsito planetário: a busca por exoplanetas tipo Terra em estrelas frias

Abstract

Since 2009, when it was launched, the Kepler space telescope has given and continues to provide important data for understanding stellar behavior, in addition to being a great tool for the search of exoplanets, among them Earth types. The analysis of the light spectra captured by the nearly 21 Kepler modules or sensors (42 CCDs - Charge Couple Devices), close to the regions of Lyra and Cygnus constellations, offers a wealth of important information about the characteristics of the cosmo. A set of 34 stars (demonstrably without planets) of type M (cold and small stars), obtained by the satellite and deeply studied by Savita Mathur [1], was used for the analysis of variability in order to understand the behavior of this stellar type. Type M stars are strong candidates for the presence of Jupyter-type and Earth-type planets with short translation periods. Astrophysicists are constantly searching for Earth-like planets, in search of intelligent life, or even for a future shelter, making the exoplanetology field the probable future of astrophysics. Thus, in chapter 2 we will introduce the definition of exoplanets and explain the reason for using the planetary transit method, showing basic concepts of exoplanetology. In chapter 3 we will show the data used as well as its composition. In addition, we will show how the data were treated to obtain variability and to search for exoplanets. In chapter 4 we will show the use of the transit method using the Transit Least Squares program [2] to search for an Earth-like exoplanet in a habitable zone, showing that the search for new Earths and new worlds is possible with good treatments and good data. In the chapter 5 we will show some information and details of the sample used in this work. Finally, in the chapter 6 we will show the results of calculating the magnetic indices of Mathur et al.[1] for the sample stars.