Astrotomography

Astrotomography: micro-arcsecond resolution indirect imaging from time-resolved observations. Keith Horne (St. Andrews)

Astrotomography uses time-resolved measurements of astrophysical sources to measure projections from which micro-arcsecond angular resolution can be achieved indirectly. The methods involved are related to but generally more compicated than those used in the Computer Assisted Tomography and other medical imaging applications. Astrotomography methods measure projections of the source image by using a mix of doppler shifts, time delays, and occultations, assisted in some cases by rotation of the system under study (e.g. rotating star, revolving binary system).

Stellar surface imaging employs Doppler shifts, occultations, and Zeeman measurements to map surface temperature and magnetic field structure on rotating stars. Eclipse Mapping and Doppler Tomography resolve the 2-dimensional structure of accretion flows in close binary systems including cataclysmic variables and X-ray binaries. Echo mapping combines light travel time delays and Doppler shifts to construct two-dimensional maps of the broad emission-line regions associated with accretion onto supermassive black holes in active galactic nuclei.

The workshop will feature brief presentations by expert practitioners with ample time for discussion.