Mr. Bernd Freytag Profile

Bernd Freytag

at Uppsala Univ

SPIE Involvement:

Author

Publications (1)

This will count as one of your downloads.

You will have access to both the presentation and article (if available).

DOWNLOAD NOW

This content is available for download via your institution's subscription. To access this item, please sign in to your personal account.

Email or Username Forgot your username?

Password Forgot your password?

Show

Keep me signed in

No SPIE account? Create an account

Proceedings Article | 21 February 2003 Paper

Alpha Ori imaging science

Bernd Freytag

Proceedings Volume 4838, (2003) https://doi.org/10.1117/12.458826

KEYWORDS: Convection, Opacity, Numerical simulations, Stars, Ionization, Astronomy, Solar energy, Computer simulations, Electromagnetic coupling, Acoustics

Read Abstract +

Three-dimensional radiation hydrodynamics simulation of the convective envelope and the atmosphere of a red supergiant (e.g. α Ori) have been performed, including ionization effects and realistic (grey) opacities. Only a handful of giant convection cells with lifetimes up to a few years are found in the envelope. The stellar surface itself is covered with smaller short-lived cells related to the well-known solar granulation but differing in many ways. Pressure fluctuations, acoustic waves, and shocks play an important role affecting the surface energy fluxes and accordingly the emitted intensity. The interaction with convection and waves generates observable large-scale high-contrast surface features. The complexity of the surface structures in the numerical models which will probably be even higher in nature calls for interferometric observations with high spatial and some temporal resolution. The comparison with the results of numerical simulations will allow to deduce information about the nature of the surface phenomena and fundamental stellar parameters.

My Library

You currently do not have any folders to save your paper to! Create a new folder below.

Folder Name

Folder Description

View contact details

UPDATE YOUR PROFILE

Is this your profile? Update it now.

Sign into your SPIE.org account

Don’t have a profile and want one?

Create an account on SPIE.org

Access to the requested content is limited to institutions that have purchased or subscribe to SPIE eBooks. You are receiving this notice because your organization may not have SPIE eBooks access.*

*Shibboleth/Open Athens users─please sign in to access your institution's subscriptions.

To obtain this item, you may purchase the complete book in print or electronic format on SPIE.org.

ORGANIZATIONAL
Sign in with credentials provided by your organization.

Organizational Username

Organizational Password

Show/Hide Password

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

;

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE

Includes PDF, HTML & Video, when available

Members:

Non-members: ADD TO CART

Keywords/Phrases

Search In:

Publication Years