High Resolution VLBI Astrometry of pulsar scintillation screens with the $\theta -\theta$ Transform

Abstract

The recent development of $θ\mhyphenθ$ techniques in pulsar scintillometry has opened the door for new high resolution imaging techniques of the scattering medium. By solving the phase retrieval problem and recovering the wavefield from a pulsar dynamic spectrum, the Doppler shift, time delay, and phase offset of individual images can be determined. However, the results of phase retrieval from a single dish are only known up to a constant phase rotation, which introduces extra parameters when doing astrometry using Very Long Baseline Interferometry. We present an extension to previous $θ\mhyphenθ$ methods using the interferometric visibilities between multiple stations to calibrate the wavefields. When applied to existing data for PSR B0834+06 we measure the effective screen distance and lens orientation with five times greater precision than previous works.

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Cited by in corpus (5)

• Scintillation Properties of PSR B1133+16 Measured with Very Long Baseline Interferometry
• Pulsar Cyclic Spectroscopy in the Partial-Deconvolution Regime: Benefits & Limitations
• Pulsar scattering as a probe for structures in the interstellar medium
• Investigating Extreme Scattering Events by Volumetric Ray-tracing
• Imaging without visibilities: FAST-Effelsberg scintillometry of PSR B1508+55