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Helioseismic Studies of Differential Rotation in the Solar Envelope by the Solar Oscillations Investigation Using the Michelson Doppler Imager
The splitting of the frequencies of the global resonant acoustic modes of the Sun by large-scale flows and rotation permits study of the variation of angular velocity Ω with both radius and latitudeExpand
The Current State of Solar Modeling
Data from the GONG project and other helioseismic experiments reveal subtle errors in the models, such as an excess in sound speed just beneath the convection zone, which is plausible that the sound-speed differences reflect weak mixing in stellar interiors. Expand
Differential Rotation and Dynamics of the Solar Interior
Frequency splittings derived from GONG observations confirm that the variation of rotation rate with latitude seen at the surface carries through much of the convection zone, at the base of which is an adjustment layer leading to latitudinally independent rotation at greater depths. Expand
Convective instability in a compressible atmosphere
The degree of convective instability as expressed by the growth rate ω of linear modes, is calculated for a plane parallel polytropic atmosphere in the presence of radiative damping, without usingExpand
Temporal variations in the Sun's rotational kinetic energy
Aims. We study the variation of the angular momentum and the rotational kinetic energy of the Sun, and associated variations in the gravitational multipole moments, on a timescale of the solar cycle.Expand
Seismology of the solar f-mode. I. Basic signatures of shearing velocity fields
The observed frequencies of the solar f-mode show systematic shifts from the (parabolic) dispersion relation characteristic of a pure surface mode, owing to the perturbing effects of such phenomenaExpand
The Sun's acoustic asphericity and magnetic fields in the solar convection zone
The observed splittings of solar oscillation frequencies can be employed to separate the effects of internal solar rotation and to estimate the contribution from a large-scale magnetic field or anyExpand
The Seismic Structure of the Sun
Global Oscillation Network Group data reveal that the internal structure of the sun can be well represented by a calibrated standard model. However, immediately beneath the convection zone and at theExpand
Solar Rotation Rate and Its Gradients During Cycle 23
Available helioseismic data now span almost the entire solar activity cycle 23, making it possible to study solar-cycle-related changes of the solar rotation rate in detail. In this paper we studyExpand