Interferometric Studies of Hot Stars at Sydney University

TL;DR

This paper reviews the history and capabilities of Sydney University's optical interferometry facilities, highlighting their focus on hot star observations and recent upgrades to improve remote operation and scientific output.

Contribution

It details the development and upgrade of SUSI, emphasizing its suitability for hot star studies and the transition to remote operation for expanded research.

Findings

Measured angular diameters of hot stars

Established temperature scale for spectral classes O - F

Enhanced interferometry capabilities with PAVO upgrade

Abstract

The University of Sydney has a long history in optical stellar interferometry. The first project, in the 1960s, was the Narrabri Stellar Intensity Interferometer, which measured the angular diameters of 32 hot stars and established the temperature scale for spectral classes O - F. That instrument was followed by the Sydney University Stellar Interferometer (SUSI), which is now undergoing a third-generation upgrade, to use the multi-wavelength PAVO beam combiner. SUSI operates at visible rather than IR wavelengths and has baselines up to 160 m, so it is well suited to the study of hot stars. A number of studies have been carried out, and more are planned when commissioning of the PAVO system is complete. Conversion of the system to allow remote operation will allow larger scientific projects to be undertaken.