Astronomy Astrophysics manuscript no. (will be inserted by hand later) On the theory of MAG waves and a comparison with sunspot observations from CDS/SoHO D. Banerjee 1 , E. O'Shea 2 , M. Goossens 1 , J.G.Doyle 3 , and S. Poedts 1 1 Centre for Plasma Astrophysics, Katholieke ... We nd oscillations in the chromosphere and transition region above the sunspots in the temperature range log T = 4.6-5.4 K. Most of the spectral power above the umbra is contained in the 5-7 mHz frequency range. ...