Program Prospectus

Tentative program as of July 11, 2012.

Key topics

Where the observations come from:

• Ground-based surveys and programs (OGLE, MACHO, WASP, HATNet, etc.)
• Spectrophotometric surveys
• Space observatories (MOST, Corot, Kepler)

What physical information on stars can be determined from high-precision photometry?

The state of solar and stellar models and their weaknesses and uncertainties.

Advanced tests of stellar structure from seismology:

• Measuring the depth of stellar convective envelopes
• Measuring the helium ionization discontinuity, which indicates the helium abundance
• Inferring internal rotation in stars
• Measuring the depth of composition discontinuities, such as the H/He layer in white dwarfs
• Inferring radial differential rotation

Stellar population studies enabled by seismology:

• Measuring mass, radius, and age from seismology
• The complementarity of seismology and conventional observations in setting fundamental parameters such as temperature and composition
• Using results from seismology to improve and calibrate empirical age properties such as rotation and activity

Going beyond the star as a perfect sphere:

• Understanding the origin and evolution of stellar magnetic fields and activity. Do magnetic fields influence stellar structure? Can we explain solar-like winds? How does activity affect habitability in the circumstellar environment?
• Rotation in all kinds of stars and angular momentum transport. Does rotation drive interior mixing? Does rapid rotation trigger supernovae?
• What are the origins of highly-magnetized stars?
• What determines the extent of convective regions, especially convective cores, in massive stars?
• What causes mass loss in massive stars? Is most of the mass lost during the main sequence, or in severe episodes after?
• What is the physics of mass loss in cool giants? Is most mass in first ascent giants lost at the helium flash or before?
• Interacting binaries are thought to generate many interesting classes of objects; do we have the story right? For example, do SN Ia arise from a single or double degenerate origin?
• Do we understand chemical evolution?

Pulsating stars in a new light from space and from the ground:

• δ Scuti stars
• β Cephei stars
• RoAp stars
• Slowly-pulsating B stars

Compact stars (e.g., white dwarfs) and their variability

Singular and unusual phenomena

Eruptive and flaring behavior in stars

The growth, evolution, and decay of spots on late-type stars

Binary stars as tests of stellar models, including eclipsing binaries

The future for precision tests:

• What's needed from models
• New projects and missions (e.g., SONG, WFIRST, LSST, Pan-Starrs)

Important Note

Joint Discussion 13 is part of the scientific programme of the XXVIII General Assembly of the International Astronomical Union, which will take place in Beijing, China, August 27-31 2012. This website contains information directly relevant to the Special Session #13: High-Precision Tests of Stellar Physics from High-Precision Photometry. Please check the GA website for all other information, including accommodations, social program, Visa information, etc.