Speaker
Description
We present end-to-end simulations of intensity interferometry of bright binary stars, built on a full photon-counting budget for a generic state-of-the-art SPAD Lambda. Dispersing the starlight along the array makes every pixel pair an independent narrowband channel measuring its own g², and because the pair correlation's sensitivity is bandwidth-independent, spectral multiplexing converts the classic marginality of small-aperture intensity interferometry into routine measurement. With current detectors, 1-m-class pairs can detect the binary signature of systems like β Aurigae in a night, while 10-m-class pairs measure the full g²(λ) spectrum — binary fringes, limb-darkened disk envelopes, and the eclipse-driven reorganization of systems like Algol — on hour timescales. The natural next step is the triple correlation: the bispectrum's signal-to-noise, unlike the pair's, rewards spectral resolution directly, which motivates a next-generation detector placing the same timing architecture behind an R~5000 dispersing backend. Deployed on the VLT Telescopes — whose baselines are well matched to milliarcsecond binaries — such an instrument would measure closure phases of Spica and δ Velorum in minutes, tracking them around the orbit. These would be the first astrophysical closure phases recovered from intensity correlations, opening orbit-resolved apsidal-motion and gravity-darkening science, and ultimately model-independent imaging, to stellar intensity interferometry.
