uu.seUppsala University Publications
Change search
ReferencesLink to record
Permanent link

Direct link
VLTI/AMBER Studies of the Atmospheric Structure and Fundamental Parameters of Red Giant and Supergiant Stars
Univ Valencia, Dept Astron & Astrofis, E-46100 Burjassot, Spain..
ESO, Garching, Germany..
Univ Valencia, Dept Astron & Astrofis, E-46100 Burjassot, Spain.;Donostia Int Phys Ctr, Donostia San Sebastian, Spain..
Univ Valencia, Dept Astron & Astrofis, E-46100 Burjassot, Spain..
Show others and affiliations
2015 (English)In: WHY GALAXIES CARE ABOUT AGB STARS III: A CLOSER LOOK IN SPACE AND TIME, ASTRONOMICAL SOC PACIFIC , 2015, Vol. 497, 91-96 p.Conference paper (Refereed)Text
Abstract [en]

We present recent near-IR interferometric studies of red giant and super giant stars, which are aimed at obtaining information on the structure of the atmospheric layers and constraining the fundamental parameters of these objects. The observed visibilities of six red supergiants (RSGs), and also of one of the five red giants observed, indicate large extensions of the molecular layers, as previously observed for Mira stars. These extensions are not predicted by hydrostatic PHOENIX model atmospheres, hydrodynamical (RED) simulations of stellar convection, or self-excited pulsation models. All these models based on parameters of RSGs lead to atmospheric structures that are too compact compared to our observations. We discuss how alternative processes might explain the atmospheric extensions for these objects. As the continuum appears to be largely free of contamination by molecular layers, we can estimate reliable Rosseland angular radii for our stars. Together with distances and bolometric fluxes, we estimate the effective temperatures and luminosities of our targets, locate them in the HR diagram, and compare their positions to recent evolutionary tracks.

Place, publisher, year, edition, pages
ASTRONOMICAL SOC PACIFIC , 2015. Vol. 497, 91-96 p.
National Category
Astronomy, Astrophysics and Cosmology
Identifiers
URN: urn:nbn:se:uu:diva-294830ISI: 000371098100012ISBN: 9781583818794OAI: oai:DiVA.org:uu-294830DiVA: diva2:953817
Conference
Conference on Why Galaxies Care About AGB Stars III: A Closer Look in Space and Time, JUL 28-AUG 01, 2014, Univ Vienna, Vienna, AUSTRIA
Available from: 2016-08-18 Created: 2016-05-27 Last updated: 2016-08-18Bibliographically approved

Open Access in DiVA

No full text

Search in DiVA

By author/editor
Freytag, Bernd
By organisation
Theoretical Astrophysics
Astronomy, Astrophysics and Cosmology

Search outside of DiVA

GoogleGoogle Scholar
The number of downloads is the sum of all downloads of full texts. It may include eg previous versions that are now no longer available

Total: 73 hits
ReferencesLink to record
Permanent link

Direct link