The DIFOS photometer was designed to study global oscillations of the solar radiation.
The photometer provided continuous series of observations of solar brightness in three
spectral ranges with the general duration of 52 days. The power spectra of global oscillations
of the Sun reveal p-modes of the order l=0,1,2. The frequency splitting
of p-modes as a result of solar rotation was demonstrated experimentally.
The dynamics of p-modes
The spectra for 6 two-day time series are shown. The adjacent time series are shifted for 15 hours.
It permits to follow the changes of p-modes amplitudes with time.
The p-mode with l=1, n=23 decreases in amplitide and finally disappears.
The p-mode with l=1, n=19 emerges during the time of observation.
There are no observable changes of the amplitude of p-mode l=1, n=20.
On the left: the sum of spectra for two-day 15 hours shifted intervals is shown.
Total time interval of the spectra covers 52 days. The shape of the spectrum and amplitudes of
p-modes are in good accordance with the previous observations.
On the right: the Echelle diagram for the upper spectrum.
The ridges for l=0, 1, 2 are clearely recognized on the diagram.
The rotational splitting of the solar oscillations.
A frequency split for the l=1 and l=2 corresponds to the theoretical value.
There is no splitting for l=0.