Observations of solar oscillations of low and intermediate degree

  title={Observations of solar oscillations of low and intermediate degree},
  author={T. Duvall and J. Harvey},
Measurements are presented of solar velocity oscillations with spherical harmonic degree 1–139 and angular order ∼0. With an amplitude sensitivity of ∼2 cm s −1, trapped acoustic wave modes of radial orders 2–26 are observed at frequencies between 1.7 and 5.5 mHz. The radial order identifications of low-degree modes previously inferred from theory are confirmed. Only marginal evidence of long-period, gravity-mode oscillations is found 
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