Bibcode
Gelly, B.; Fierry-Fraillon, D.; Fossat, E.; Pallé, P. L.; Cacciani, A.; Ehgamberdiev, S.; Grec, G.; Hoeksema, J. T.; Khalikov, S.; Lazrek, M.; Loudagh, S.; Pantel, A.; Régulo, C.; Schmider, F. X.
Bibliographical reference
Astronomy and Astrophysics, v.323, p.235-242
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7
1997
Journal
Citations
12
Refereed citations
10
Description
The Iris network for helioseismology has operated since 1989. We present
tables of solar p-mode frequencies for observations taken during the
four summer seasons from 1989 to 1992. This analysis uses the technique
of maximum likelihood fitting and a χ_2_^2^ model for the
probability density function of the spectrum. The simultaneous fitting
of odd and even pairs of peaks strengthens the identification of the l=3
eigenmodes and improves the error bars on the 0-2 group. The frequencies
are in good agreement with other observational results and with
theoretical values for the D_0_ and the {DELTA}ν parameters of the
asymptotic approximation. A decrease of 0.25+/-0.12μHz is seen
between the 1989 and the 1992 data sets. The change is associated with
the decrease of solar activity and is comparable with results of
previous studies.