Bibcode
Ulrich, R. K.; García, R. A.; Robillot, J.-M.; Turck-Chièze, S.; Bertello, L.; Charra, J.; Dzitko, H.; Gabriel, A. H.; Roca-Cortés, T.
Bibliographical reference
Astronomy and Astrophysics, v.364, p.799-815 (2000)
Advertised on:
12
2000
Journal
Citations
42
Refereed citations
26
Description
The GOLF instrument provides a stable and continuous measurement of the
intensity of spatially integrated sunlight in one wing of the sodium D
lines. Because the detected radiation results from atomic scattering,
the GOLF signal can be traced to an atomic reference wavelength. The
planned operations were to involve a form of relative photometry through
the use of measurements on both the blue and red wings of the solar D
lines of neutral sodium. However, due to the occasional malfunction of
the polarization subsystem a ``one wing photometric mode" operational
alternative has been selected in order to ensure achievement of a 100%
duty cycle. In this case, the signal observed consists of two
photometric measurements at only one wing of each line of the sodium
doublet separated by gx0.43 picometers (pm). The sodium cell system in
GOLF combines photons scattered at three different wavelengths: one at
D_1 and two at D_2. This paper developes a formalism to describe this
system in terms of the solar spectral line profiles. A method of
converting the one wing data to an effective velocity scale is
presented. The method is applied to the nearly continuous 804 day
sequence received from the GOLF instrument prior to the loss of
telecommunications with SOHO on 24-June-1998. The resulting time
sequence is part of the GOLF archive and can be made available to
investigators. This publication describes some properties of this time
series.