Asteroseismology: sonic probing of stellar interiors

The proposed research programme addresses unsolved problems in stellar physics, using helioseismological and asteroseismological techniques. Helioseismology is the science of inferring the nature of the inside of the Sun from a study of the properties of sound waves that are trapped inside. Asteroseismology is the same applied to other stars. The techniques resemble those used by geophysicists for determining the internal state of the Earth.
The purpose of this proposal is to combine expertise in stellar evolution and asteroseismology with the objectives developing, testing and applying diagnostic tools that are necessary to exploit fully the asteroseismic data from stars with solar-like oscillations. There is no better time than now to make rapid progress. The range of stars in which oscillations can be observed is expanding enormously, particularly as a result of the advent of new high-quality data from the very successful French space mission CoRoT, NASA's up-coming Kepler mission, the Austro-Canadian satellite BRITE-constellation and ground-based observations such as those from the new Danish Stellar Oscillation Network Group (SONG). We shall interpret the enormous amount of these high-quality seismic stellar data, The research plans are based around the following highly topical problems: (i) the development of a cleaner separation of the contributions to the mode frequencies that relate to different physical attributes of a star,(ii) the formalism of the interaction between convection and pulsation, and (iii) the understanding of the near-surface layers of the Sun, and thence of solar-type stars and red giants too. For example, the results of this study will lead to an independent and more accurate determination of stellar ages and stellar chemical abundances, both of which are of great importance to other fields in astronomy, such as the chemical evolution of the Galaxy, and hence of the Universe. The consequences are bound to elevate to new heights the sophistication of the theory of the evolution of stars, the backbone of theoretical astrophysics.
In addition to extant stellar-oscillation data from ground-based and space-born observations, NASA's up-coming Kepler mission will also hunt for planets outside our solar system. This work will help to determine some key properties of planet-hosting stars, and will provide crucial information, such as the planetary radii, and help to determine whether or not the planets are capable of sustaining life.