EDP Sciences Journals List
Advanced Search
Subscriber Authentication Point
Home All issues Volume 398/2 Article
Free access article

Issue A&A
Volume 398, Number 2, February I 2003
Page(s) 411 - 421
Section Cosmology
DOI http://dx.doi.org/10.1051/0004-6361:20021605



A&A 398, 411-421 (2003)
DOI: 10.1051/0004-6361:20021605

Magnetic intensification of spectral lines

M. J. Stift1 and F. Leone2

1  Institut für Astronomie (IfA), Universität Wien, Türkenschanzstrasse 17, 1180 Wien, Austria
2  INAF, Osservatorio Astrofisico di Catania, Via S. Sofia n. 78, 95123 Catania, Italy
    e-mail: fleone@ct.astro.it

(Received 26 June 2002 / Accepted 25 October 2002 )

Abstract
We present an in-depth investigation of the increase in equivalent width of saturated lines under the influence of strong magnetic fields, aptly called "magnetic intensification". Assuming 20 different Zeeman patterns (with the number of components ranging from 3 to 45) for a fictitious Fe II line at 4500 Å in a 10 000 K, $\log g = 4.0$ Kurucz atmosphere, we calculate equivalent widths as a function of magnetic field strength, field angle and line strength (abundance). The increase over the zero field equivalent width is found to always fall below the n/2 relation suggested by Babcock (1949), where n is the number of Zeeman components. After a discussion of the behaviour of various Zeeman patterns we turn to the influence of anomalous dispersion on magnetic intensification. Changes in line blanketing due to magnetic desaturation appear to be of negligible size. Finally we show that magnetic intensification leads to apparent enhanced abundances and to virtual abundance variations in magnetic stars with dipolar surface magnetic field configurations.


Key words: stars: abundances -- stars: chemically peculiar -- stars: magnetic fields -- polarization

Offprint request: M. J. Stift, stift@astro.univie.ac.at

SIMBAD Objects



© ESO 2003


What is OpenURL?

The OpenURL standard is a protocol for transmission of metadata describing the resource that you wish to access. An OpenURL link contains article metadata and directs it to the OpenURL server of your choice. The OpenURL server can provide access to the resource and also offer complementary services (specific search engine, export of references...). The OpenURL link can be generated by different means.
  • If your librarian has set up your subscription with an OpenURL resolver, OpenURL links appear automatically on the abstract pages.
  • You can define your own OpenURL resolver with your EDPS Account. In this case your choice will be given priority over that of your library.
  • You can use an add-on for your browser (Firefox or I.E.) to display OpenURL links on a page (see http://www.openly.com/openurlref/). You should disable this module if you wish to use the OpenURL server that you or your library have defined.