Bibcode
Pallé, P. L.; GOLF Team; Roca-Cortés, T.; Gabriel, A. H.
Bibliographical reference
Advances in Space Research, Volume 11, Issue 4, p. 103-112.
Advertised on:
1
1991
Journal
Citations
0
Refereed citations
0
Description
The GOLF experiment on the SOHO mission will study the internal
structure of the sun by measuring the spectrum of global oscillations in
the frequency range 10-7 to 6 10-3 Hz. Both p and
g mode oscillations will be investigated, with the emphasis on the low
order long period waves which penetrate the solar core. The instrument
employs an extension to space of the proven ground-based technique for
measuring the mean line-of-sight velocity of the viewed solar surface. A
sodium vapour resonance filter is used in a longitudinal magnetic field
to sample the two wings of the solar absorption line. The addition of a
small modulating field component enables the slope of the wings to be
measured. This provides not only an internal calibration of the
instrument sensitivity, but also opens the possibility to recognise, and
correct for, the solar background signal produced by the effects of
solar magnetically active regions. The use of an additional rotating
polariser enables also measurement of the mean solar line-of sight
magnetic field.
(see final Section)