Demonstration of a digital intensity interferometry system with the StarBase observatory

A modern implementation of intensity interferometry onto current and future optical telescope arrays allows for unprecedented angular resolution capabilities (< 1 mas) at short optical wavelengths (U/B/V bands). The technique is well suited for observing and characterizing hot main-sequence stars, primarily of O,B, or A spectral types. Observations at the pathfinder observatory, StarBase, located in Grantsville, UT, have demonstrated the feasibility of implementing the technique onto current and future Imaging Air Cherenkov telescopes, constructed for gamma-ray astronomy. In this talk, I present the optical and electronic system used in these observations that have led to a preliminary detection of the signal associated with the spatial coherence of the source. Furthermore, recent developments allow for a “wireless” mode, as demonstrated by the synchronization of separated data acquisition systems to nanosecond timescales. The system is portable, and plans are underway to test the system on a distributed array of large diameter (12 m) Imaging Air Cherenkov telescopes in Fall 2018.