Bibcode
DOI
Eff-Darwich, A.; Korzennik, S. G.; Jiménez-Reyes, S. J.; Pérez Hernández, F.
Referencia bibliográfica
The Astrophysical Journal, Volume 580, Issue 1, pp. 574-578.
Fecha de publicación:
11
2002
Revista
Número de citas
25
Número de citas referidas
19
Descripción
We have analyzed changes in the acoustic oscillation eigenfrequencies
measured over the past 7 years by the GONG, MDI, and LOWL instruments.
The observations span the period from 1994 to 2001 that corresponds to
half a solar cycle, from minimum to maximum solar activity. These data
were inverted to look for a signature of the activity cycle on the solar
stratification. A one-dimensional structure inversion was carried out to
map the temporal variation of the radial distribution of the sound speed
at the boundary between the radiative and convective zones. Such
variation could indicate the presence of a toroidal magnetic field
anchored in this region. We found no systematic variation with time of
the stratification at the base of the convection zone. However, we can
set an upper limit to any fractional change of the sound speed at the
level of 3×10-5.