HDUST inhales He: probing the hotter inner parts of gaseous disks by the inclusion of helium in the radiative transfer analysis

• Grant number: 15/16592-0
• Support Opportunities: Scholarships abroad - Research
• Start date: December 01, 2015
• End date: January 31, 2016
• Field of knowledge: Physical Sciences and Mathematics - Astronomy - Stellar Astrophysics
• Principal Investigator: Alex Cavaliéri Carciofi
• Grantee: Alex Cavaliéri Carciofi
• Host Investigator: Dietrich Baade
• Host Institution: Instituto de Astronomia, Geofísica e Ciências Atmosféricas (IAG). Universidade de São Paulo (USP). São Paulo , SP, Brazil
• Institution abroad: European Southern Observatory, Munich (ESO), Germany

Abstract

HDUST is a radiative transfer code developed by prof. Carciofi (IAG/USP) in collaboration with prof. Jon Bjorkman (Univ. of Toledo, USA). This code was in the core of our research in the past decade or so, and its application in the field of Be star research allowed for important contributions in our understanding of the central object and its circumstellar disk. Recently, major advances were implemented in HDUST that is now capable of handling He and other elements (in addition to H) in the NLTE regime and in three-dimensional configurations. This new version of HDUST offers new and quite exciting scientific opportunities that will be actively pursued in the coming months. Our main goals are i) to study how the inclusion of He will affect the thermal structure of the disk for a broad range of disk and stellar parameters, and ii) how the He I and II lines can be used to probe and constrain the properties of the inner parts of Be disks. The proposed 2-month visit to the European Southern Observatory in Munich, Germany, will allow a close interaction between the proponent and Dr. Dietrich Baade in a critical phase of the project. During the visit the theoretical results of HDUST for the He I and II line profiles, for several B spectral subtypes, will be confronted to the rich observational data of Dr. Baade, spanning many decades of spectroscopic observations of Be stars. Three publications are expected to result from this project. (AU)

Scientific publications

(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)

BAADE, D.; RIVINIUS, TH.; PIGULSKI, A.; CARCIOFI, A. C.; MARTAYAN, CH.; MOFFAT, A. F. J.; WADE, G. A.; WEISS, W. W.; GRUNHUT, J.; HANDLER, G.; et al. Short-term variability and mass loss in Be stars I. BRITE satellite photometry of eta and mu Centauri. Astronomy & Astrophysics, v. 588, APR 2016. (15/16592-0)