Banca de DEFESA: LUCIANO LUIZ ALENCAR DE OLIVEIRA

Uma banca de DEFESA de DOUTORADO foi cadastrada pelo programa.
STUDENT : LUCIANO LUIZ ALENCAR DE OLIVEIRA
DATE: 16/12/2019
TIME: 09:00
LOCAL: Auditório do CCET
TITLE:

A ROTAÇÃO ESTELAR REVELADA PELA MODULAÇÃO FOTOMÉTRICA

KEY WORDS:

stellar models, rotation period, projected rotation velocity, discontinuity, Hertzsprung-Russell diagram.

PAGES: 95
BIG AREA: Ciências Exatas e da Terra
AREA: Física
SUMMARY:

Rotation is one of the most important parameters in astrophysics and its effects are observed in all evolutionary stage, since the beginning. This present work shows an analysis of the rotation from photometric measures along the Hertzsprung-Russell diagram (HR diagram), for stars in different evolutionary stages, such as: main sequence, subgiants, giants, bright giants and supergiants Ib. We use stellar evolution models with rotation, in which the metallicity are z = 0, 002 and z = 0, 014, presented respectively by Georgy et al. (2013b) and Ekström et al. (2012). Through the measurement of angular rotation velocities, presented in the models, we estimate the rotation period for each evolutionary track (with masses ranging from 0, 8M
 < M ≤ 20M
) and consequently we determine the rotation isoperiodic lines using the interpolation technique cubic spline for a effective temperature region 3.500 < Tef ≤ 10.500 K and luminosity −1, 0 < Log (L/L
) ≤ 5, 5. The interpolation technique was utilized to the mean values ±5% of the desired measurements, which are 5, 15, 25, 50 and 100 days. Combining the isoperiods with the distribution of our sample’s rotation period values, we observe that there is a significant congruence between the theoretical data and the observational data, even though another analysis may indicate a divergence. In addition, our results show that the discontinuity of the rotation period happens gradually and in every luminosity class, in the vertical direction (depending only on the stellar mass), as well as in the horizontal direction (depending on the effective temperature) in the HR

diagram.

BANKING MEMBERS:
Interno - 1675216 - BRUNO LEONARDO CANTO MARTINS
Interno - 3060853 - IZAN DE CASTRO LEÃO
Presidente - 346785 - JOSE RENAN DE MEDEIROS
Externo à Instituição - LEONARDO ANDRADE DE ALMEIDA - UERN
Externa à Instituição - MARIA LIDUINA DAS CHAGAS - UNIFESSPA