EDP Sciences
Free Access
Issue
A&A
Volume 412, Number 1, December II 2003
Page(s) 241 - 248
Section Formation and evolution of planetary systems
DOI https://doi.org/10.1051/0004-6361:20031405


A&A 412, 241-248 (2003)
DOI: 10.1051/0004-6361:20031405

The limb-darkening for spherically symmetric NextGen model atmospheres: A-G main-sequence and sub-giant stars

A. Claret1 and P. H. Hauschildt2

1  Instituto de Astrofísica de Andalucía, CSIC, Apartado 3004, 18080 Granada, Spain
2  Hamburger Sternwarte, Gojenbergsweg 112, 21029 Hamburg, Germany
    e-mail: Peter.Hauschildt@hs.uni-hamburg.de

(Received 4 June 2003 / Accepted 29 August 2003 )

Abstract
We compute passband-integrated specific intensities for spherically symmetric models generated with the PHOENIX code. The models cover the range $5000~{\rm K} \le T_{\rm eff}\le 10\,000$ K with surface gravities between 3.5 and 5.5, in steps of 0.5. The adopted mixing-length parameter is 2.0 pressure scale heights, while the microturbulent velocity is 2.0 km s -1. The calculations were carried out for four photometric systems: Strömgren, Johnson, Geneva and Walraven, completing 24 filters. The series introduced by Claret (2000) and a new bi-parametric (exponential) law are shown to be able to describe the intensity distribution of spherical models with acceptable  $\sigma$. Simple limb-darkening laws do not produce accurate fits to the computed radiation fields. On the other hand, the concept of "quasi" spherical models is introduced and we present the corresponding limb-darkening coefficients for the most commonly adopted limb-darkening laws for the same filters.


Key words: stars: atmospheres -- stars: binaries: eclipsing

Offprint request: A. Claret, claret@iaa.es




© ESO 2003

Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.

Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.

Initial download of the metrics may take a while.