T Tauri stars physical parameters: excitation and ionization equilibrium in the spectral lines formation

• Grant number: 20/16251-6
• Support Opportunities: Scholarships in Brazil - Scientific Initiation
• Start date: March 01, 2021
• End date: February 28, 2022
• Field of knowledge: Physical Sciences and Mathematics - Astronomy - Stellar Astrophysics
• Principal Investigator: Jane Cristina Gregorio-Hetem
• Grantee: Joao Victor Correa Rodrigues
• Host Institution: Instituto de Astronomia, Geofísica e Ciências Atmosféricas (IAG). Universidade de São Paulo (USP). São Paulo , SP, Brazil

Abstract

We will perform optical spectral lines measurements of T Tauri stars aiming to estimate stellar parameters such as effective temperature, gravity and metallicity. One of the goals is to provide to the student the learning of statistical physics involved in the formation and characterization of spectral lines. Such learning cannot be acquired from the automatic estimates provided by using available codes of stellar models. Through the Saha and Boltzmann equations, we intend to obtain the growth curve by searching for the excitation and ionization equilibrium of Fe lines measured in stars for which the physical parameters are well known. The second phase of the project is dedicated to a sample of T Tauri stars for which GMOS spectra are available. The targets are weak-lined T Tauri stars associated with a star-forming scenario suggested to be result from supernova events. By this way, both goals of the project can be achieved: the learning of the physical processes related to the formation of spectral lines, as well as to obtain stellar parameters in order to complete the characterization of a selected sample of T Tauri stars aiming to better understand their early stages of star formation.