Source depth for solar p-modes
  Theoretically calculated power spectra are compares with observed solar p-mode velocity power spectra over a range of mode degree and frequency. The depth for the sources responsible for exciting p-modes of frequency 2.0 mHz is determined from the asymmetry of their power spectra and found to be about 800 km below the photosphere for quadrupole sources and 150 km if sources are dipole. The source depth for high frequency oscillations of frequency greater than about 6 mHz is 180 (50) km for quadrupole (dipole) sources. 
Pawan Kumar (IAS), Sarbani Basu (Yale)