100 Microarcsecond Resolution VLBI Imaging of Anisotropic Interstellar Scattering towards Pulsar B0834+06

Understand

We have invented a novel technique to measure the radio image of a pulsar scattered by the interstellar plasma with 0.1 mas resolution.

• We extend the "secondary spectrum" analysis of parabolic arcs by Stinebring et al.
• (2001) to very long baseline interferometry and, when the scattering is anisotropic, we are able to map the scattered brightness astrometrically with much higher resolution than the diffractive limit of the interferometer.
• We employ this technique to measure an extremely anisotropic scattered image of the pulsar B0834+06 at 327 MHz.