Multiline Zeeman signatures through line addition - Archive ouverte HAL Accéder directement au contenu
Article Dans Une Revue Astronomy and Astrophysics - A&A Année : 2009

Multiline Zeeman signatures through line addition

Résumé

Context: To obtain a significant Zeeman signature in the polarised spectra of a magnetic star, we usually ``add'' the contributions of numerous spectral lines; the ultimate goal is to recover the spectropolarimetric prints of the magnetic field in these line additions.
Aims: Here we want to clarify the meaning of these techniques of line addition; in particular, we try to interpret the meaning of the ``pseudo-line'' formed during this process and to find out why and how its Zeeman signature is still meaningful.
Methods: We create a synthetic case of line addition and apply well tested standard solar methods routinely used in research on magnetism in the Sun.
Results: The results are convincing and the Zeeman signatures well detected; Solar methods are found to be quite efficient for stellar observations. We statistically compare line addition with least-squares deconvolution and demonstrate that they both give very similar results, as a consequence of the special statistical properties of the weights.
Conclusions: The Zeeman signatures are unequivocally detected in this multiline approach. We suggest that magnetic field detection is reliable well beyond the weak-field approximation. Linear polarisation in the spectra of solar type stars can be detected when the spectral resolution is sufficiently high.

Dates et versions

hal-03785506 , version 1 (23-09-2022)

Identifiants

Citer

Meir Semel, J. C. Rámirez Vélez, María Jesús Martínez González, Andrés Asensio-Ramos, Martin J. Stift, et al.. Multiline Zeeman signatures through line addition. Astronomy and Astrophysics - A&A, 2009, 504, pp.1003-1009. ⟨10.1051/0004-6361/200810428⟩. ⟨hal-03785506⟩
7 Consultations
0 Téléchargements

Altmetric

Partager

Gmail Mastodon Facebook X LinkedIn More