Probing atmospheres and circumstellar environments of Be stars and evolved low mass stars with interferometry and polarimetry

• Grant number: 09/07477-1
• Support Opportunities: Scholarships in Brazil - Post-Doctoral
• Start date: November 01, 2009
• End date: April 30, 2012
• Field of knowledge: Physical Sciences and Mathematics - Astronomy - Stellar Astrophysics
• Principal Investigator: Alex Cavaliéri Carciofi
• Grantee: Xavier Marie Alain Haubois
• Host Institution: Instituto de Astronomia, Geofísica e Ciências Atmosféricas (IAG). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Associated research grant: 06/59453-0 - Photoionized nebulae, stars and the chemical evolution of galaxies, AP.TEM

Abstract

This project has the goal of bringing Dr. Xavier Haubois to collaborate with the Interferometry Group of IAG/USP in the acquisition, reduction and modeling of interferometric and polarimetric data of Be stars and low-mass evolved stars. The project has two different and somewhat independent research lines:1) Be Stars. This class of object has been extensively studied by modern interferometers that are capable of angularly resolving these objects in unprecedented details, allowing for studying many physical processes of great astrophysical interest such as stellar rotation, dynamic processes in astrophysical disks, etc. The initial objective is to model the 2006 epoch of the circumstellar disk of Be star Achernar, for which our group has a very detailed observational dataset, using the radiative transfer code HDUST.2) AGB stars. The second and more ambitious research line consists of using HDUST to study asymmetries present in AGB stars. This will involve extensions to the code in order to make it capable of handling interferometric and polarimetric data of these objects. This ambitious project is supported by the applicant's expertise on AGB stars, acquired during his PhD work, and by the supervisor's expertise in radiative transfer. Globally, Dr. Haubois will participate in a new collaboration between the supervisor, Prof. Alex C. Carciofi, and Profs. Walter Maciel and Roberto Costa of IAG. Furthermore, Dr. Haubois will support an existing collaboration between the supervisor and the Interferometry Group of the University of Nice (Dr. Domiciano de Souza and collaborators).Part of the planned activities is within the scope of the Fapesp Theme Project 2006/59453-0. (AU)

Scientific publications

(5)

(References retrieved automatically from Web of Science and SciELO through information on FAPESP grants and their corresponding numbers as mentioned in the publications by the authors)

CARCIOFI, ALEX C.; BJORKMAN, JON E.; OTERO, SEBASTIAN A.; OKAZAKI, ATSUO T.; STEFL, STANISLAV; RIVINIUS, THOMAS; BAADE, DIETRICH; HAUBOIS, XAVIER. THE FIRST DETERMINATION OF THE VISCOSITY PARAMETER IN THE CIRCUMSTELLAR DISK OF A Be STAR. Astrophysical Journal Letters, v. 744, n. 1, JAN 1 2012. (10/19029-0, 10/16037-2, 09/07477-1)

DRAPER, ZACHARY H.; WISNIEWSKI, JOHN P.; BJORKMAN, KAREN S.; HAUBOIS, XAVIER; CARCIOFI, ALEX C.; BJORKMAN, JON E.; MEADE, MARILYN R.; OKAZAKI, ATSUO. A NEW DIAGNOSTIC OF THE RADIAL DENSITY STRUCTURE OF Be DISKS. Astrophysical Journal Letters, v. 728, n. 2, FEB 20 2011. (09/07477-1)

HAUBOIS, X.; MOTA, B. C.; CARCIOFI, A. C.; DRAPER, Z. H.; WISNIEWSKI, J. P.; BEDNARSKI, D.; RIVINIUS, TH. DYNAMICAL EVOLUTION OF VISCOUS DISKS AROUND BE STARS. II. POLARIMETRY. ASTROPHYSICAL JOURNAL, v. 785, n. 1, APR 10 2014. (09/54006-4, 10/19029-0, 09/07477-1)

TAN, LUN C.; REAMES, DONALD V.; NG, CHEE K.; SHAO, XI; WANG, LINGHUA. CORRELATION OF ELECTRON PATH LENGTHS OBSERVED IN THE HIGHLY WOUND OUTER REGION OF MAGNETIC CLOUDS WITH THE SLAB FRACTION OF MAGNETIC TURBULENCE IN THE DISSIPATION RANGE. ASTROPHYSICAL JOURNAL, v. 786, n. 2, MAY 10 2014. (10/19029-0, 09/07477-1)

HAUBOIS, X.; CARCIOFI, A. C.; RIVINIUS, TH; OKAZAKI, A. T.; BJORKMAN, J. E.. DYNAMICAL EVOLUTION OF VISCOUS DISKS AROUND Be STARS. I. PHOTOMETRY. ASTROPHYSICAL JOURNAL, v. 756, n. 2, SEP 10 2012. (09/54006-4, 10/19029-0, 10/16037-2, 09/07477-1)