High frequency and high wavenumber solar oscillations

We determine the frequencies of solar oscillations covering a wide range of degree (100< l <4000) and frequency (1.5 <ν<10 mHz) using the ring diagram technique applied to power spectra obtained from MDI (Michelson Doppler Imager) data. The f-mode ridge extends up to degree of approximately 3000, where the line width becomes very large, implying a damping time which is comparable to the time period. The frequencies of high degree f-modes are significantly different from those given by the simple...