Searching for l = 1 modes of solar oscillations

An instrument to measure the non-full-disk low-order solar oscillations that uses a magneto-optical filter in Na-D lines is described. It has the advantage, over the resonant cells used by other observers, that it gives an image of the Sun and a higher photonic flux.Proceedings of the 14th ESLAB Symposium on Physics of Solar Variations, 16–19 September 1980, Scheveningen, The Netherlands.