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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
Seismic measurement of the depth of the solar convection zone
The observed frequencies of solar oscillations have been used to determine the depth of the convection zone. The effect of diffusion of helium and heavy elements on this measurement is studied and itExpand
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
Recent analyses of solar photospheric abundances suggest that the oxygen abundance in the solar atmosphere needs to be revised downward. In this study, we investigate the consequence of this revisionExpand
Standing on the Shoulders of Dwarfs: the Kepler Asteroseismic LEGACY Sample. II.Radii, Masses, and Ages
We use asteroseismic data from the Kepler satellite to determine fundamental stellar properties of the 66 main-sequence targets observed for at least one full year by the mission. We distributed tensExpand
Helioseismology and Solar Abundances
Helioseismology has allowed us to study the structure of the Sun in unprecedented detail. One of the triumphs of the theory of stellar evolution was that helioseismic studies had shown that theExpand
Helium abundance in the solar envelope
The variations in the adiabatic index in the second helium ionization zone of the Sun allow us to infer the helium abundance in the solar envelope using the observed solar oscillation frequencies.Expand
The Discrepancy between Solar Abundances and Helioseismology
There have been recent downward revisions of the solar photospheric abundances of oxygen and other heavy elements. These revised abundances along with OPAL opacities are not consistent with seismicExpand
Numerical Methods for Scientists and Engineers
1 Introduction 2 Roundoff Error 3 Linear Algebraic Equations 4 Interpolation 5 Differentiation 6 Integration 7 Nonlinear Algebraic Equations 8 Optimisation 9 Statistical Inferences 10 FunctionalExpand