Dynamical modeling of Be star disks using polarimetry and spectroscopy

• Grant number: 25/23117-8
• Support Opportunities: Scholarships in Brazil - Master
• Start date: April 01, 2026
• End date: August 31, 2027
• Field of knowledge: Physical Sciences and Mathematics - Astronomy - Stellar Astrophysics
• Principal Investigator: Alex Cavaliéri Carciofi
• Grantee: Laize Abreu Gemelli
• Host Institution: Instituto de Astronomia, Geofísica e Ciências Atmosféricas (IAG). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 18/04055-8 - High precision spectroscopy: from the first stars to planets, AP.TEM

Abstract

This master's project aims to advance the group's previous efforts in developing a model for the evolution of Be star disks. It builds on an earlier research project that focused on the star Achernar. In that work, the singlebe code, which simulates viscous disks in 1D, and hdust, a radiative transfer code, were used to model the polarimetric and spectroscopic variability of Achernar during the formation and dissipation of its disk (2013-2016). The attempt to model this event using polarimetric data was unprecedented at the time. Since this observable provides information about the inner and intermediate regions of the disk, it enables a better understanding of the behavior of these regions over time. In particular, we seek to investigate the limitations found in previous simulations. One of these limitations is the simplified hydrodynamics used in singlebe. To address this, we will adopt a hydrodynamical modeling based on Smoothed Particle Hydrodynamics (SPH), which provides a more realistic description than that of singlebe. The goal of this work is to assess whether a more rigorous hydrodynamical approach can resolve the discrepancies between the model and the observations. We will do this by combining SPH with hdust and comparing the resulting simulations with those obtained previously using singlebe and hdust. With this approach, we expect to contribute to a better understanding of the physical processes governing Be star disks. (AU)