Made available in DSpace on 2014-12-17T15:14:58Z (GMT). No. of bitstreams: 1 FranciscoJC_DISSERT.pdf: 1252788 bytes, checksum: 79f23bcf558ba802fceb9767f5de4082 (MD5) Previous issue date: 2012-03-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / In this work, we analyze the behavior of the chromospheric and coronal activities as a function of the mass and the orbital period of extrasolar planets which were detected by transit technique. So we look for possible effects of the planet on the star s chromosphere and corona. For this study we selected a sample of 48 stars with chromospheric activity indicator and 23 with coronal activity indicator. Our work is based on the work from Pont et al. (2011) in order to study stars with planets which were obtained by transit technique. Furthermore, we studied the relationship between planetary mass and orbital period with the chromospheric and coronal activity in order to better understand which influences the planets cause in the outer layers of stellar atmosphere. In our analysis we can observe that the mass of the planets exerts no influence in the stellar activity. However, we observed that the stellar coronal and chromospheric activities decrease with the increase of the orbital period of the planet / Neste trabalho, analisamos o comportamento da atividade cromosf?rica e coronal em fun??o da massa e do per?odo orbital de planetas extrassolares que foram detectados atrav?s da t?cnica de tr?nsito. Desta forma, procuramos poss?veis efeitos do planeta sobre a cromosfera e a coroa da estrela. Para este estudo selecionamos uma amostra de 48 estrelas com indicador de atividade cromosf?rica e 23 estrelas com indicador de atividade coronal. Tomamos como modelo o trabalho de Pont et al. (2011) afim de estudar estrelas com planetas os quais foram obtidos atrav?s da t?cnica de tr?nsito. Portanto, estudamos a rela??o massa-per?odo planet?rio com a atividade cromosf?rica e coronal no intuito de compreender melhor quais as influ?ncias que os planetas causam nas camadas mais externas da atmosfera estelar. Em nossa an?lise podemos observar que a massa do planeta n?o exerce nenhuma influ?ncia na atividade estelar. No entanto, podemos observar que as atividades cromosf?rica e coronal diminuem com o aumento do per?odo orbital do planeta