EDP Sciences
Free access
Issue
A&A
Volume 394, Number 1, October IV 2002
Page(s) 285 - 297
Section The Sun
DOI http://dx.doi.org/10.1051/0004-6361:20021106


A&A 394, 285-297 (2002)
DOI: 10.1051/0004-6361:20021106

Solar ${\vec p}$-modes from 1979 days of the GOLF experiment

B. Gelly1, M. Lazrek1, 2, 3, G. Grec3, A. Ayad1, 4, F. X. Schmider1, C. Renaud3, D. Salabert1 and E. Fossat1

1  Laboratoire d'Astrophysique, UMR 6525 du CNRS, Université de Nice-Sophia Antipolis, 06108 Nice Cedex 2, France
2  C.N.R., 52 Charii Omar Ibn El Khattab, BP 8027, Rabat, Morocco
3  Département Cassini, UMR 6529 du CNRS, Observatoire de la Côte d'Azur, 06304 Nice, France
4  Laboratoire de Physique des Hautes Énergies et Astrophysique, Université Cadi Ayyad, Marrakech, Morocco

(Received 26 March 2002 / Accepted 10 July 2002)

Abstract
With the GOLF instrument onboard the SoHO observatory, 1979 days of full-disc Doppler velocity observations have been compiled into a study of p-mode properties. We develop a multi-step iterative method (MSIM) algorithm to access all p-mode parameters while minimizing any perturbating effect or cross-talk between parameters during their determination. We present frequency and splitting tables, amplitudes, linewidths, line asymmetries, pseudo-modes, and background noise determinations. We have a first look at the changes induced by the transition from the low-activity to the high-activity part of solar cycle 23: we have recorded frequency shifts with a downturn at 3.7 mHz followed by a possible higher upturn, and linewidth changes to a good accuracy. We detect an effect on the noise background at 3 mHz possibly related to an interaction between noise and the modes and connected to the asymmetry of the profiles.


Key words: Sun: oscillations -- Sun: helioseismology

Offprint request: B. Gelly, gelly@unice.fr




© ESO 2002

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.