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arXiv · astro-ph/9811154

High frequency and high wavenumber solar oscillations

H. M. Antia·Sarbani Basu
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Abstract

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 dispersion relation ω^2=gk. The f-mode peaks in power spectra are distinctly asymmetric and use of asymmetric profile increases the fitted frequency bringing them closer to the frequencies computed for a solar model.

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H. M. Antia, Sarbani Basu. 1999-02-10. High frequency and high wavenumber solar oscillations. https://doi.org/10.1086/307364

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