Capabilities of future intensity interferometers for observing fast-rotating stars: imaging with two- and three-telescope correlations

TL;DR

Future large arrays of telescopes used as intensity interferometers could revolutionize stellar surface imaging, especially for fast-rotating stars, by capturing detailed phenomena like gravity darkening and rotational deformation with enhanced resolution.

Contribution

This paper demonstrates the potential of future intensity interferometers with two- and three-telescope correlations for high-resolution imaging of fast-rotating stars, highlighting the benefits of higher order correlations.

Findings

Two-telescope data enable reasonable imaging of stellar phenomena.

Three-telescope correlations improve imaging quality by providing Fourier phase information.

Intensity interferometry can effectively image gravity darkening and rotational deformation.

Abstract

Future large arrays of telescopes, used as intensity interferometers, can be used to image the surfaces of stars with unprecedented angular resolution. Fast-rotating, hot stars are particularly attractive targets for intensity interferometry since shorter (blue) wavelength observations do not pose additional challenges. Starting from realistic surface brightness simulations of fast-rotating stars, we discuss the capabilities of future intensity interferometers for imaging effects such as gravity darkening and rotational deformation. We find that two-telescope intensity correlation data allow reasonably good imaging of these phenomena, but can be improved with additional higher order (e.g. three-telescope) correlation data, which contain some Fourier phase information.