Year: 2026
Type: preprint
Abstract: Optical intensity interferometry (II) can in principle resolve structure on angular scales $θ\sim λ/B$, but it measures only the squared visibility $|{\cal V}|^2$, discarding Fourier phase. We quantify what information can actually be recovered from phase-less $|{\cal V}|^2$ measurements as a function of the aggregate signal-to-noise ratio and array configuration, using score-based diffusion models as non-parametric image priors. We construct an image reconstruction pipeline, and validate it by reconstructing a variety of images, including GRMHD simulations of black hole accretion disks and actual SDO/HMI continuum images of the Sun, from phase-less Fourier amplitudes. Using simulated data, we map the reconstruction fidelity of Sun-like stellar surfaces as a function of noise level, number of $(u,v)$ samples, and maximum baseline $B_{\rm max}$, for surface maps spanning a range of activity levels. We find that fidelity depends on the data only through the total signal to noise ratio (SNR) of the surface features of interest, provided that the $(u,v)$ plane is sampled sufficiently densely. These results show that the SNR levels achieved by next-generation intensity interferometers observing realistic sources are sufficient to image highly complicated stellar surfaces.
Source: arXiv (Cornell University)
Authors: Dalal, Neal, Dai, Biwei, Browning, Matthew K.
Language: English
Subfield: Atomic and Molecular Physics, and Optics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: green
Funders: Ambrose Monell Foundation, Aspen Center for Physics, Corning Incorporated Foundation, Innovation, Science and Economic Development Canada, Government of Canada, Ministero dello Sviluppo Economico, Alliance de recherche numérique du Canada, Institut Périmètre de physique théorique, Science and Technology Facilities Council
OpenAlex ID: W7211995644