Interferometric-Doppler imaging of stellar surface structure

Doppler imaging of stellar surface structure

We present a time series of Doppler images of the RS CVn binary V711 Tauri from spectra taken during 57 consecutive nights in November and December 1996. VRI-band APT photometry throughout the entire observing season is used to support the Doppler imaging. A set of altogether 37 overlapping images from the Ca i-6439 line allows us to trace the latitudinal and longitudinal migration of individua...

Stellar Surface Imaging Using Closure Phase

We describe the use of interferometry to make images of features on the surfaces of cool stars. We describe observations of Betelgeuse (α Ori) and use this example to illustrate the requirements for astrophysical imaging with interferometers. We emphasise the importance of obtaining closure phase measurements and good Fourier plane coverage when imaging complex objects.

Optoacoustic imaging based on the interferometric measurement of surface displacement.

We present images of tissue phantoms and chicken chorio-allantoic membrane vasculature using a novel optoacoustic tomography technique based on the time-resolved interferometric measurement of laser-induced thermoelastic expansion. Our imaging system is based on a modified Mach-Zehnder interferometer that provides surface displacement measurements with a temporal resolution of 4 ns and a displa...

Interferometric and Holographic Imaging of Surface-Breaking Cracks

Interferometric science results on young stellar objects

Long-baseline interferometry at infrared wavelengths allows the innermost regions around young stars to be observed. These observations directly probe the location of the dust and gas in the disks. The characteristic sizes of these regions found are larger than previously thought. These results have motivated in part a new class of models of the inner disk structure, but the precise understandi...