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Three-minute oscillations over sunspot's umbra in AR 11131 were observedsimultaneously in UV/EUV emission by SDO/AIA and in radio emission by NobeyamaRadioheliograph (NoRH). We use 24-hours series of SDO and 8-hours series ofNoRH observations to study spectral, spatial and temporal variations ofpulsations in the 5-9 mHz frequency range at different layers of the solaratmosphere. High spatial and temporal resolution of SDO/AIA in combination withlong-duration observations allowed us to trace the variations of the cut-offfrequency and spectrum of oscillations across the umbra. We found that higherfrequency oscillations are more pronounced closer to the umbra's center, whilethe lower frequencies concentrate to the peripheral parts. We interpreted thisdiscovery as a manifestation of variation of the magnetic field inclinationacross the umbra at the level of temperature-minimum. Possible implications ofthis interpretation for the diagnostics of sunspot atmospheres is discussed.

Three-minute oscillations above sunspot umbra observed with SDO/AIA and NoRH